perlapi - autogenerated documentation for the perl public API
This file contains most of the documentation of the perl public API, as generated by embed.pl. Specifically, it is a listing of functions, macros, flags, and variables that may be used by extension writers. Besides perlintern and config.h, some items are listed here as being actually documented in another pod.
At the end is a list of functions which have yet to be documented. Patches welcome! The interfaces of these are subject to change without notice.
Some of the functions documented here are consolidated so that a single entry serves for multiple functions which all do basically the same thing, but have some slight differences. For example, one form might process magic, while another doesn't. The name of each variation is listed at the top of the single entry. But if all have the same signature (arguments and return type) except for their names, only the usage for the base form is shown. If any one of the forms has a different signature (such as returning const
or not) every function's signature is explicitly displayed.
Anything not listed here or in the other mentioned pods is not part of the public API, and should not be used by extension writers at all. For these reasons, blindly using functions listed in proto.h is to be avoided when writing extensions.
In Perl, unlike C, a string of characters may generally contain embedded NUL
characters. Sometimes in the documentation a Perl string is referred to as a "buffer" to distinguish it from a C string, but sometimes they are both just referred to as strings.
Note that all Perl API global variables must be referenced with the PL_
prefix. Again, those not listed here are not to be used by extension writers, and may be changed or removed without notice; same with macros. Some macros are provided for compatibility with the older, unadorned names, but this support may be disabled in a future release.
Perl was originally written to handle US-ASCII only (that is characters whose ordinal numbers are in the range 0 - 127). And documentation and comments may still use the term ASCII, when sometimes in fact the entire range from 0 - 255 is meant.
The non-ASCII characters below 256 can have various meanings, depending on various things. (See, most notably, perllocale.) But usually the whole range can be referred to as ISO-8859-1. Often, the term "Latin-1" (or "Latin1") is used as an equivalent for ISO-8859-1. But some people treat "Latin1" as referring just to the characters in the range 128 through 255, or sometimes from 160 through 255. This documentation uses "Latin1" and "Latin-1" to refer to all 256 characters.
Note that Perl can be compiled and run under either ASCII or EBCDIC (See perlebcdic). Most of the documentation (and even comments in the code) ignore the EBCDIC possibility. For almost all purposes the differences are transparent. As an example, under EBCDIC, instead of UTF-8, UTF-EBCDIC is used to encode Unicode strings, and so whenever this documentation refers to utf8
(and variants of that name, including in function names), it also (essentially transparently) means UTF-EBCDIC
. But the ordinals of characters differ between ASCII, EBCDIC, and the UTF- encodings, and a string encoded in UTF-EBCDIC may occupy a different number of bytes than in UTF-8.
The organization of this document is tentative and subject to change. Suggestions and patches welcome perl5-porters@perl.org.
The sections in this document currently are
The listing below is alphabetical, case insensitive.
AvARRAY
Returns a pointer to the AV's internal SV* array.
This is useful for doing pointer arithmetic on the array. If all you need is to look up an array element, then prefer av_fetch
.
SV** AvARRAY(AV* av)
av_clear
Frees all the elements of an array, leaving it empty. The XS equivalent of @array = ()
. See also "av_undef".
Note that it is possible that the actions of a destructor called directly or indirectly by freeing an element of the array could cause the reference count of the array itself to be reduced (e.g. by deleting an entry in the symbol table). So it is a possibility that the AV could have been freed (or even reallocated) on return from the call unless you hold a reference to it.
void av_clear(AV *av)
av_count
Returns the number of elements in the array av
. This is the true length of the array, including any undefined elements. It is always the same as av_top_index(av) + 1
.
Size_t av_count(AV *av)
av_create_and_push
Push an SV onto the end of the array, creating the array if necessary. A small internal helper function to remove a commonly duplicated idiom.
NOTE: av_create_and_push
must be explicitly called as Perl_av_create_and_push
with an aTHX_
parameter.
void Perl_av_create_and_push(pTHX_ AV ** const avp,
SV * const val)
av_create_and_unshift_one
Unshifts an SV onto the beginning of the array, creating the array if necessary. A small internal helper function to remove a commonly duplicated idiom.
NOTE: av_create_and_unshift_one
must be explicitly called as Perl_av_create_and_unshift_one
with an aTHX_
parameter.
SV ** Perl_av_create_and_unshift_one(pTHX_ AV ** const avp,
SV * const val)
av_delete
Deletes the element indexed by key
from the array, makes the element mortal, and returns it. If flags
equals G_DISCARD
, the element is freed and NULL is returned. NULL is also returned if key
is out of range.
Perl equivalent: splice(@myarray, $key, 1, undef)
(with the splice
in void context if G_DISCARD
is present).
SV * av_delete(AV *av, SSize_t key, I32 flags)
av_exists
Returns true if the element indexed by key
has been initialized.
This relies on the fact that uninitialized array elements are set to NULL
.
Perl equivalent: exists($myarray[$key])
.
bool av_exists(AV *av, SSize_t key)
av_extend
Pre-extend an array so that it is capable of storing values at indexes 0..key
. Thus av_extend(av,99)
guarantees that the array can store 100 elements, i.e. that av_store(av, 0, sv)
through av_store(av, 99, sv)
on a plain array will work without any further memory allocation.
If the av argument is a tied array then will call the EXTEND
tied array method with an argument of (key+1)
.
void av_extend(AV *av, SSize_t key)
av_fetch
Returns the SV at the specified index in the array. The key
is the index. If lval
is true, you are guaranteed to get a real SV back (in case it wasn't real before), which you can then modify. Check that the return value is non-NULL before dereferencing it to a SV*
.
See "Understanding the Magic of Tied Hashes and Arrays" in perlguts for more information on how to use this function on tied arrays.
The rough perl equivalent is $myarray[$key]
.
SV ** av_fetch(AV *av, SSize_t key, I32 lval)
AvFILL
Same as "av_top_index"
or "av_tindex"
.
SSize_t AvFILL(AV* av)
av_fill
Set the highest index in the array to the given number, equivalent to Perl's $#array = $fill;
.
The number of elements in the array will be fill + 1
after av_fill()
returns. If the array was previously shorter, then the additional elements appended are set to NULL. If the array was longer, then the excess elements are freed. av_fill(av, -1)
is the same as av_clear(av)
.
void av_fill(AV *av, SSize_t fill)
av_len
Same as "av_top_index". Note that, unlike what the name implies, it returns the maximum index in the array. This is unlike "sv_len", which returns what you would expect.
To get the true number of elements in the array, instead use "av_count"
.
SSize_t av_len(AV *av)
av_make
Creates a new AV and populates it with a list (**strp
, length size
) of SVs. A copy is made of each SV, so their refcounts are not changed. The new AV will have a reference count of 1.
Perl equivalent: my @new_array = ($scalar1, $scalar2, $scalar3...);
AV * av_make(SSize_t size, SV **strp)
av_pop
Removes one SV from the end of the array, reducing its size by one and returning the SV (transferring control of one reference count) to the caller. Returns &PL_sv_undef
if the array is empty.
Perl equivalent: pop(@myarray);
SV * av_pop(AV *av)
av_push
Pushes an SV (transferring control of one reference count) onto the end of the array. The array will grow automatically to accommodate the addition.
Perl equivalent: push @myarray, $val;
.
void av_push(AV *av, SV *val)
av_push_simple
This is a cut-down version of av_push that assumes that the array is very straightforward - no magic, not readonly, and AvREAL - and that key
is not less than -1. This function MUST NOT be used in situations where any of those assumptions may not hold.
Pushes an SV (transferring control of one reference count) onto the end of the array. The array will grow automatically to accommodate the addition.
Perl equivalent: push @myarray, $val;
.
void av_push_simple(AV *av, SV *val)
av_shift
Removes one SV from the start of the array, reducing its size by one and returning the SV (transferring control of one reference count) to the caller. Returns &PL_sv_undef
if the array is empty.
Perl equivalent: shift(@myarray);
SV * av_shift(AV *av)
av_store
Stores an SV in an array. The array index is specified as key
. The return value will be NULL
if the operation failed or if the value did not need to be actually stored within the array (as in the case of tied arrays). Otherwise, it can be dereferenced to get the SV*
that was stored there (= val
)).
Note that the caller is responsible for suitably incrementing the reference count of val
before the call, and decrementing it if the function returned NULL
.
Approximate Perl equivalent: splice(@myarray, $key, 1, $val)
.
See "Understanding the Magic of Tied Hashes and Arrays" in perlguts for more information on how to use this function on tied arrays.
SV ** av_store(AV *av, SSize_t key, SV *val)
av_tindex
av_top_index
These behave identically. If the array av
is empty, these return -1; otherwise they return the maximum value of the indices of all the array elements which are currently defined in av
.
They process 'get' magic.
The Perl equivalent for these is $#av
.
Use "av_count"
to get the number of elements in an array.
SSize_t av_tindex(AV *av)
av_undef
Undefines the array. The XS equivalent of undef(@array)
.
As well as freeing all the elements of the array (like av_clear()
), this also frees the memory used by the av to store its list of scalars.
See "av_clear" for a note about the array possibly being invalid on return.
void av_undef(AV *av)
av_unshift
Unshift the given number of undef
values onto the beginning of the array. The array will grow automatically to accommodate the addition.
Perl equivalent: unshift @myarray, ((undef) x $num);
void av_unshift(AV *av, SSize_t num)
get_av
Returns the AV of the specified Perl global or package array with the given name (so it won't work on lexical variables). flags
are passed to gv_fetchpv
. If GV_ADD
is set and the Perl variable does not exist then it will be created. If flags
is zero (ignoring SVf_UTF8
) and the variable does not exist then NULL
is returned.
Perl equivalent: @{"$name"}
.
NOTE: the perl_get_av()
form is deprecated.
AV * get_av(const char *name, I32 flags)
newAV
newAV_mortal
newAV_alloc_x
newAV_alloc_xz
These all create a new AV, setting the reference count to 1. If you also know the initial elements of the array with, see "av_make
".
As background, an array consists of three things:
A data structure containing information about the array as a whole, such as its size and reference count.
A C language array of pointers to the individual elements. These are treated as pointers to SVs, so all must be castable to SV*.
The individual elements themselves. These could be, for instance, SVs and/or AVs and/or HVs, etc.
An empty array need only have the first data structure, and all these functions create that. They differ in what else they do, as follows:
newAV
formThis does nothing beyond creating the whole-array data structure. The Perl equivalent is approximately my @array;
This is useful when the minimum size of the array could be zero (perhaps there are likely code paths that will entirely skip using it).
If the array does get used, the pointers data structure will need to be allocated at that time. This will end up being done by "av_extend">, either explicitly:
av_extend(av, len);
or implicitly when the first element is stored:
(void)av_store(av, 0, sv);
Unused array elements are typically initialized by av_extend
.
newAV_mortal
formThis also creates the whole-array data structure, but also mortalises it. (That is to say, a reference to the AV is added to the temps
stack.)
newAV_alloc_x
formThis effectively does a newAV
followed by also allocating (uninitialized) space for the pointers array. This is used when you know ahead of time the likely minimum size of the array. It is more efficient to do this than doing a plain newAV
followed by an av_extend
.
Of course the array can be extended later should it become necessary.
size
must be at least 1.
newAV_alloc_xz
formThis is newAV_alloc_x
, but initializes each pointer in it to NULL. This gives added safety to guard against them being read before being set.
size
must be at least 1.
The following examples all result in an array that can fit four elements (indexes 0 .. 3):
AV *av = newAV();
av_extend(av, 3);
AV *av = newAV_alloc_x(4);
AV *av = newAV_alloc_xz(4);
In contrast, the following examples allocate an array that is only guaranteed to fit one element without extending:
AV *av = newAV_alloc_x(1);
AV *av = newAV_alloc_xz(1);
AV * newAV ()
AV * newAV_mortal ()
AV * newAV_alloc_x (SSize_t size)
AV * newAV_alloc_xz(SSize_t size)
newAVav
Creates a new AV and populates it with values copied from an existing AV. The new AV will have a reference count of 1, and will contain newly created SVs copied from the original SV. The original source will remain unchanged.
Perl equivalent: my @new_array = @existing_array;
AV * newAVav(AV *oav)
newAVhv
Creates a new AV and populates it with keys and values copied from an existing HV. The new AV will have a reference count of 1, and will contain newly created SVs copied from the original HV. The original source will remain unchanged.
Perl equivalent: my @new_array = %existing_hash;
AV * newAVhv(HV *ohv)
Nullav
DEPRECATED!
It is planned to remove Nullav
from a future release of Perl. Do not use it for new code; remove it from existing code.
Null AV pointer.
(deprecated - use (AV *)NULL
instead)
call_argv
Performs a callback to the specified named and package-scoped Perl subroutine with argv
(a NULL
-terminated array of strings) as arguments. See perlcall.
Approximate Perl equivalent: &{"$sub_name"}(@$argv)
.
NOTE: the perl_call_argv()
form is deprecated.
SSize_t call_argv(const char *sub_name, I32 flags, char **argv)
call_method
Performs a callback to the specified Perl method. The blessed object must be on the stack. See perlcall.
NOTE: the perl_call_method()
form is deprecated.
SSize_t call_method(const char *methname, I32 flags)
call_pv
Performs a callback to the specified Perl sub. See perlcall.
NOTE: the perl_call_pv()
form is deprecated.
SSize_t call_pv(const char *sub_name, I32 flags)
call_sv
Performs a callback to the Perl sub specified by the SV.
If neither the G_METHOD
nor G_METHOD_NAMED
flag is supplied, the SV may be any of a CV, a GV, a reference to a CV, a reference to a GV or SvPV(sv)
will be used as the name of the sub to call.
If the G_METHOD
flag is supplied, the SV may be a reference to a CV or SvPV(sv)
will be used as the name of the method to call.
If the G_METHOD_NAMED
flag is supplied, SvPV(sv)
will be used as the name of the method to call.
Some other values are treated specially for internal use and should not be depended on.
See perlcall.
NOTE: the perl_call_sv()
form is deprecated.
SSize_t call_sv(SV *sv, I32 flags)
ENTER_with_name
Same as "ENTER"
, but when debugging is enabled it also associates the given literal string with the new scope.
ENTER_with_name("name");
eval_pv
Tells Perl to eval
the given string in scalar context and return an SV* result.
NOTE: the perl_eval_pv()
form is deprecated.
SV * eval_pv(const char *p, I32 croak_on_error)
eval_sv
Tells Perl to eval
the string in the SV. It supports the same flags as call_sv
, with the obvious exception of G_EVAL
. See perlcall.
The G_RETHROW
flag can be used if you only need eval_sv() to execute code specified by a string, but not catch any errors.
By default the code is compiled and executed with the default hints, such as strict and features. Set G_USEHINTS
in flags to use the current hints from PL_curcop
.
NOTE: the perl_eval_sv()
form is deprecated.
SSize_t eval_sv(SV *sv, I32 flags)
FREETMPS
Closing bracket for temporaries on a callback. See "SAVETMPS"
and perlcall.
FREETMPS;
GIMME
DEPRECATED!
It is planned to remove GIMME
from a future release of Perl. Do not use it for new code; remove it from existing code.
A backward-compatible version of GIMME_V
which can only return G_SCALAR
or G_LIST
; in a void context, it returns G_SCALAR
. Deprecated. Use GIMME_V
instead.
U32 GIMME
GIMME_V
The XSUB-writer's equivalent to Perl's wantarray
. Returns G_VOID
, G_SCALAR
or G_LIST
for void, scalar or list context, respectively. See perlcall for a usage example.
U32 GIMME_V
is_lvalue_sub
Returns non-zero if the sub calling this function is being called in an lvalue context. Returns 0 otherwise.
I32 is_lvalue_sub()
LEAVE_with_name
Same as "LEAVE"
, but when debugging is enabled it first checks that the scope has the given name. name
must be a literal string.
LEAVE_with_name("name");
mortal_destructor_sv
This function arranges for either a Perl code reference, or a C function reference to be called at the end of the current statement.
The coderef
argument determines the type of function that will be called. If it is SvROK()
it is assumed to be a reference to a CV and will arrange for the coderef to be called. If it is not SvROK() then it is assumed to be a SvIV()
which is SvIOK()
whose value is a pointer to a C function of type DESTRUCTORFUNC_t
created using PTR2INT()
. Either way the args
parameter will be provided to the callback as a parameter, although the rules for doing so differ between the Perl and C mode. Normally this function is only used directly for the Perl case and the wrapper mortal_destructor_x()
is used for the C function case.
When operating in Perl callback mode the args
parameter may be NULL in which case the code reference is called with no arguments, otherwise if it is an AV (SvTYPE(args) == SVt_PVAV) then the contents of the AV will be used as the arguments to the code reference, and if it is any other type then the args
SV will be provided as a single argument to the code reference.
When operating in a C callback mode the args
parameter will be passed directly to the C function as a void *
pointer. No additional processing of the argument will be peformed, and it is the callers responsibility to free the args
parameter if necessary.
Be aware that there is a signficant difference in timing between the end of the current statement and the end of the current pseudo block. If you are looking for a mechanism to trigger a function at the end of the current pseudo block you should look at "SAVEDESTRUCTOR_X
" in perlapi instead of this function.
void mortal_destructor_sv(SV *coderef, SV *args)
save_aelem
save_aelem_flags
These each arrange for the value of the array element av[idx]
to be restored at the end of the enclosing pseudo-block.
In save_aelem
, the SV at C**sptr> will be replaced by a new undef
scalar. That scalar will inherit any magic from the original **sptr
, and any 'set' magic will be processed.
In save_aelem_flags
, SAVEf_KEEPOLDELEM
being set in flags
causes the function to forgo all that: the scalar at **sptr
is untouched. If SAVEf_KEEPOLDELEM
is not set, the SV at C**sptr> will be replaced by a new undef
scalar. That scalar will inherit any magic from the original **sptr
. Any 'set' magic will be processed if and only if SAVEf_SETMAGIC
is set in in flags
.
void save_aelem (AV *av, SSize_t idx, SV **sptr)
void save_aelem_flags(AV *av, SSize_t idx, SV **sptr,
const U32 flags)
save_helem
save_helem_flags
These each arrange for the value of the hash element (in Perlish terms) $hv{key}]
to be restored at the end of the enclosing pseudo-block.
In save_helem
, the SV at C**sptr> will be replaced by a new undef
scalar. That scalar will inherit any magic from the original **sptr
, and any 'set' magic will be processed.
In save_helem_flags
, SAVEf_KEEPOLDELEM
being set in flags
causes the function to forgo all that: the scalar at **sptr
is untouched. If SAVEf_KEEPOLDELEM
is not set, the SV at C**sptr> will be replaced by a new undef
scalar. That scalar will inherit any magic from the original **sptr
. Any 'set' magic will be processed if and only if SAVEf_SETMAGIC
is set in in flags
.
void save_helem (HV *hv, SV *key, SV **sptr)
void save_helem_flags(HV *hv, SV *key, SV **sptr,
const U32 flags)
SAVETMPS
Opening bracket for temporaries on a callback. See "FREETMPS"
and perlcall.
SAVETMPS;
cBOOL
Cast-to-bool. When Perl was able to be compiled on pre-C99 compilers, a (bool)
cast didn't necessarily do the right thing, so this macro was created (and made somewhat complicated to work around bugs in old compilers). Now, many years later, and C99 is used, this is no longer required, but is kept for backwards compatibility.
bool cBOOL(bool expr)
I_V
Cast an NV to IV while avoiding undefined C behavior
IV I_V(NV what)
I_32
Cast an NV to I32 while avoiding undefined C behavior
I32 I_32(NV what)
U_V
Cast an NV to UV while avoiding undefined C behavior
UV U_V(NV what)
U_32
Cast an NV to U32 while avoiding undefined C behavior
U32 U_32(NV what)
Perl uses "full" Unicode case mappings. This means that converting a single character to another case may result in a sequence of more than one character. For example, the uppercase of ß
(LATIN SMALL LETTER SHARP S) is the two character sequence SS
. This presents some complications The lowercase of all characters in the range 0..255 is a single character, and thus "toLOWER_L1"
is furnished. But, toUPPER_L1
can't exist, as it couldn't return a valid result for all legal inputs. Instead "toUPPER_uvchr"
has an API that does allow every possible legal result to be returned.) Likewise no other function that is crippled by not being able to give the correct results for the full range of possible inputs has been implemented here.
toFOLD
toFOLD_A
toFOLD_utf8
toFOLD_utf8_safe
toFOLD_uvchr
These all return the foldcase of a character. "foldcase" is an internal case for /i
pattern matching. If the foldcase of character A and the foldcase of character B are the same, they match caselessly; otherwise they don't.
The differences in the forms are what domain they operate on, and whether the input is specified as a code point (those forms with a cp
parameter) or as a UTF-8 string (the others). In the latter case, the code point to use is the first one in the buffer of UTF-8 encoded code points, delineated by the arguments p .. e - 1
.
toFOLD
and toFOLD_A
are synonyms of each other. They return the foldcase of any ASCII-range code point. In this range, the foldcase is identical to the lowercase. All other inputs are returned unchanged. Since these are macros, the input type may be any integral one, and the output will occupy the same number of bits as the input.
There is no toFOLD_L1
nor toFOLD_LATIN1
as the foldcase of some code points in the 0..255 range is above that range or consists of multiple characters. Instead use toFOLD_uvchr
.
toFOLD_uvchr
returns the foldcase of any Unicode code point. The return value is identical to that of toFOLD_A
for input code points in the ASCII range. The foldcase of the vast majority of Unicode code points is the same as the code point itself. For these, and for code points above the legal Unicode maximum, this returns the input code point unchanged. It additionally stores the UTF-8 of the result into the buffer beginning at s
, and its length in bytes into *lenp
. The caller must have made s
large enough to contain at least UTF8_MAXBYTES_CASE+1
bytes to avoid possible overflow.
NOTE: the foldcase of a code point may be more than one code point. The return value of this function is only the first of these. The entire foldcase is returned in s
. To determine if the result is more than a single code point, you can do something like this:
uc = toFOLD_uvchr(cp, s, &len);
if (len > UTF8SKIP(s)) { is multiple code points }
else { is a single code point }
toFOLD_utf8
and toFOLD_utf8_safe
are synonyms of each other. The only difference between these and toFOLD_uvchr
is that the source for these is encoded in UTF-8, instead of being a code point. It is passed as a buffer starting at p
, with e
pointing to one byte beyond its end. The p
buffer may certainly contain more than one code point; but only the first one (up through e - 1
) is examined. If the UTF-8 for the input character is malformed in some way, the program may croak, or the function may return the REPLACEMENT CHARACTER, at the discretion of the implementation, and subject to change in future releases.
UV toFOLD (UV cp)
UV toFOLD_A (UV cp)
UV toFOLD_utf8 (U8* p, U8* e, U8* s, STRLEN* lenp)
UV toFOLD_utf8_safe(U8* p, U8* e, U8* s, STRLEN* lenp)
UV toFOLD_uvchr (UV cp, U8* s, STRLEN* lenp)
toLOWER
toLOWER_A
toLOWER_LATIN1
toLOWER_LC
toLOWER_L1
toLOWER_utf8
toLOWER_utf8_safe
toLOWER_uvchr
These all return the lowercase of a character. The differences are what domain they operate on, and whether the input is specified as a code point (those forms with a cp
parameter) or as a UTF-8 string (the others). In the latter case, the code point to use is the first one in the buffer of UTF-8 encoded code points, delineated by the arguments p .. e - 1
.
toLOWER
and toLOWER_A
are synonyms of each other. They return the lowercase of any uppercase ASCII-range code point. All other inputs are returned unchanged. Since these are macros, the input type may be any integral one, and the output will occupy the same number of bits as the input.
toLOWER_L1
and toLOWER_LATIN1
are synonyms of each other. They behave identically as toLOWER
for ASCII-range input. But additionally will return the lowercase of any uppercase code point in the entire 0..255 range, assuming a Latin-1 encoding (or the EBCDIC equivalent on such platforms).
toLOWER_LC
returns the lowercase of the input code point according to the rules of the current POSIX locale. Input code points outside the range 0..255 are returned unchanged.
toLOWER_uvchr
returns the lowercase of any Unicode code point. The return value is identical to that of toLOWER_L1
for input code points in the 0..255 range. The lowercase of the vast majority of Unicode code points is the same as the code point itself. For these, and for code points above the legal Unicode maximum, this returns the input code point unchanged. It additionally stores the UTF-8 of the result into the buffer beginning at s
, and its length in bytes into *lenp
. The caller must have made s
large enough to contain at least UTF8_MAXBYTES_CASE+1
bytes to avoid possible overflow.
NOTE: the lowercase of a code point may be more than one code point. The return value of this function is only the first of these. The entire lowercase is returned in s
. To determine if the result is more than a single code point, you can do something like this:
uc = toLOWER_uvchr(cp, s, &len);
if (len > UTF8SKIP(s)) { is multiple code points }
else { is a single code point }
toLOWER_utf8
and toLOWER_utf8_safe
are synonyms of each other. The only difference between these and toLOWER_uvchr
is that the source for these is encoded in UTF-8, instead of being a code point. It is passed as a buffer starting at p
, with e
pointing to one byte beyond its end. The p
buffer may certainly contain more than one code point; but only the first one (up through e - 1
) is examined. If the UTF-8 for the input character is malformed in some way, the program may croak, or the function may return the REPLACEMENT CHARACTER, at the discretion of the implementation, and subject to change in future releases.
UV toLOWER (UV cp)
UV toLOWER_A (UV cp)
UV toLOWER_LATIN1 (UV cp)
UV toLOWER_LC (UV cp)
UV toLOWER_L1 (UV cp)
UV toLOWER_utf8 (U8* p, U8* e, U8* s, STRLEN* lenp)
UV toLOWER_utf8_safe(U8* p, U8* e, U8* s, STRLEN* lenp)
UV toLOWER_uvchr (UV cp, U8* s, STRLEN* lenp)
toTITLE
toTITLE_A
toTITLE_utf8
toTITLE_utf8_safe
toTITLE_uvchr
These all return the titlecase of a character. The differences are what domain they operate on, and whether the input is specified as a code point (those forms with a cp
parameter) or as a UTF-8 string (the others). In the latter case, the code point to use is the first one in the buffer of UTF-8 encoded code points, delineated by the arguments p .. e - 1
.
toTITLE
and toTITLE_A
are synonyms of each other. They return the titlecase of any lowercase ASCII-range code point. In this range, the titlecase is identical to the uppercase. All other inputs are returned unchanged. Since these are macros, the input type may be any integral one, and the output will occupy the same number of bits as the input.
There is no toTITLE_L1
nor toTITLE_LATIN1
as the titlecase of some code points in the 0..255 range is above that range or consists of multiple characters. Instead use toTITLE_uvchr
.
toTITLE_uvchr
returns the titlecase of any Unicode code point. The return value is identical to that of toTITLE_A
for input code points in the ASCII range. The titlecase of the vast majority of Unicode code points is the same as the code point itself. For these, and for code points above the legal Unicode maximum, this returns the input code point unchanged. It additionally stores the UTF-8 of the result into the buffer beginning at s
, and its length in bytes into *lenp
. The caller must have made s
large enough to contain at least UTF8_MAXBYTES_CASE+1
bytes to avoid possible overflow.
NOTE: the titlecase of a code point may be more than one code point. The return value of this function is only the first of these. The entire titlecase is returned in s
. To determine if the result is more than a single code point, you can do something like this:
uc = toTITLE_uvchr(cp, s, &len);
if (len > UTF8SKIP(s)) { is multiple code points }
else { is a single code point }
toTITLE_utf8
and toTITLE_utf8_safe
are synonyms of each other. The only difference between these and toTITLE_uvchr
is that the source for these is encoded in UTF-8, instead of being a code point. It is passed as a buffer starting at p
, with e
pointing to one byte beyond its end. The p
buffer may certainly contain more than one code point; but only the first one (up through e - 1
) is examined. If the UTF-8 for the input character is malformed in some way, the program may croak, or the function may return the REPLACEMENT CHARACTER, at the discretion of the implementation, and subject to change in future releases.
UV toTITLE (UV cp)
UV toTITLE_A (UV cp)
UV toTITLE_utf8 (U8* p, U8* e, U8* s, STRLEN* lenp)
UV toTITLE_utf8_safe(U8* p, U8* e, U8* s, STRLEN* lenp)
UV toTITLE_uvchr (UV cp, U8* s, STRLEN* lenp)
toUPPER
toUPPER_A
toUPPER_utf8
toUPPER_utf8_safe
toUPPER_uvchr
These all return the uppercase of a character. The differences are what domain they operate on, and whether the input is specified as a code point (those forms with a cp
parameter) or as a UTF-8 string (the others). In the latter case, the code point to use is the first one in the buffer of UTF-8 encoded code points, delineated by the arguments p .. e - 1
.
toUPPER
and toUPPER_A
are synonyms of each other. They return the uppercase of any lowercase ASCII-range code point. All other inputs are returned unchanged. Since these are macros, the input type may be any integral one, and the output will occupy the same number of bits as the input.
There is no toUPPER_L1
nor toUPPER_LATIN1
as the uppercase of some code points in the 0..255 range is above that range or consists of multiple characters. Instead use toUPPER_uvchr
.
toUPPER_uvchr
returns the uppercase of any Unicode code point. The return value is identical to that of toUPPER_A
for input code points in the ASCII range. The uppercase of the vast majority of Unicode code points is the same as the code point itself. For these, and for code points above the legal Unicode maximum, this returns the input code point unchanged. It additionally stores the UTF-8 of the result into the buffer beginning at s
, and its length in bytes into *lenp
. The caller must have made s
large enough to contain at least UTF8_MAXBYTES_CASE+1
bytes to avoid possible overflow.
NOTE: the uppercase of a code point may be more than one code point. The return value of this function is only the first of these. The entire uppercase is returned in s
. To determine if the result is more than a single code point, you can do something like this:
uc = toUPPER_uvchr(cp, s, &len);
if (len > UTF8SKIP(s)) { is multiple code points }
else { is a single code point }
toUPPER_utf8
and toUPPER_utf8_safe
are synonyms of each other. The only difference between these and toUPPER_uvchr
is that the source for these is encoded in UTF-8, instead of being a code point. It is passed as a buffer starting at p
, with e
pointing to one byte beyond its end. The p
buffer may certainly contain more than one code point; but only the first one (up through e - 1
) is examined. If the UTF-8 for the input character is malformed in some way, the program may croak, or the function may return the REPLACEMENT CHARACTER, at the discretion of the implementation, and subject to change in future releases.
UV toUPPER (UV cp)
UV toUPPER_A (UV cp)
UV toUPPER_utf8 (U8* p, U8* e, U8* s, STRLEN* lenp)
UV toUPPER_utf8_safe(U8* p, U8* e, U8* s, STRLEN* lenp)
UV toUPPER_uvchr (UV cp, U8* s, STRLEN* lenp)
This section is about functions (really macros) that classify characters into types, such as punctuation versus alphabetic, etc. Most of these are analogous to regular expression character classes. (See "POSIX Character Classes" in perlrecharclass.) There are several variants for each class. (Not all macros have all variants; each item below lists the ones valid for it.) None are affected by use bytes
, and only the ones with LC
in the name are affected by the current locale.
The base function, e.g., isALPHA()
, takes any signed or unsigned value, treating it as a code point, and returns a boolean as to whether or not the character represented by it is (or on non-ASCII platforms, corresponds to) an ASCII character in the named class based on platform, Unicode, and Perl rules. If the input is a number that doesn't fit in an octet, FALSE is returned.
Variant isFOO_A
(e.g., isALPHA_A()
) is identical to the base function with no suffix "_A"
. This variant is used to emphasize by its name that only ASCII-range characters can return TRUE.
Variant isFOO_L1
imposes the Latin-1 (or EBCDIC equivalent) character set onto the platform. That is, the code points that are ASCII are unaffected, since ASCII is a subset of Latin-1. But the non-ASCII code points are treated as if they are Latin-1 characters. For example, isWORDCHAR_L1()
will return true when called with the code point 0xDF, which is a word character in both ASCII and EBCDIC (though it represents different characters in each). If the input is a number that doesn't fit in an octet, FALSE is returned. (Perl's documentation uses a colloquial definition of Latin-1, to include all code points below 256.)
Variant isFOO_uvchr
is exactly like the isFOO_L1
variant, for inputs below 256, but if the code point is larger than 255, Unicode rules are used to determine if it is in the character class. For example, isWORDCHAR_uvchr(0x100)
returns TRUE, since 0x100 is LATIN CAPITAL LETTER A WITH MACRON in Unicode, and is a word character.
Variants isFOO_utf8
and isFOO_utf8_safe
are like isFOO_uvchr
, but are used for UTF-8 encoded strings. The two forms are different names for the same thing. Each call to one of these classifies the first character of the string starting at p
. The second parameter, e
, points to anywhere in the string beyond the first character, up to one byte past the end of the entire string. Although both variants are identical, the suffix _safe
in one name emphasizes that it will not attempt to read beyond e - 1
, provided that the constraint s < e
is true (this is asserted for in -DDEBUGGING
builds). If the UTF-8 for the input character is malformed in some way, the program may croak, or the function may return FALSE, at the discretion of the implementation, and subject to change in future releases.
Variant isFOO_LC
is like the isFOO_A
and isFOO_L1
variants, but the result is based on the current locale, which is what LC
in the name stands for. If Perl can determine that the current locale is a UTF-8 locale, it uses the published Unicode rules; otherwise, it uses the C library function that gives the named classification. For example, isDIGIT_LC()
when not in a UTF-8 locale returns the result of calling isdigit()
. FALSE is always returned if the input won't fit into an octet. On some platforms where the C library function is known to be defective, Perl changes its result to follow the POSIX standard's rules.
Variant isFOO_LC_uvchr
acts exactly like isFOO_LC
for inputs less than 256, but for larger ones it returns the Unicode classification of the code point.
Variants isFOO_LC_utf8
and isFOO_LC_utf8_safe
are like isFOO_LC_uvchr
, but are used for UTF-8 encoded strings. The two forms are different names for the same thing. Each call to one of these classifies the first character of the string starting at p
. The second parameter, e
, points to anywhere in the string beyond the first character, up to one byte past the end of the entire string. Although both variants are identical, the suffix _safe
in one name emphasizes that it will not attempt to read beyond e - 1
, provided that the constraint s < e
is true (this is asserted for in -DDEBUGGING
builds). If the UTF-8 for the input character is malformed in some way, the program may croak, or the function may return FALSE, at the discretion of the implementation, and subject to change in future releases.
isALNUM
isALNUM_A
isALNUM_LC
isALNUM_LC_uvchr
These are each a synonym for their respectively named "isWORDCHAR
" variant.
They are provided for backward compatibility, even though a word character includes more than the standard C language meaning of alphanumeric. To get the C language definition, use the corresponding "isALPHANUMERIC
" variant.
bool isALNUM(UV ch)
isALNUMC
isALNUMC_A
isALNUMC_LC
isALNUMC_LC_uvchr
isALNUMC_L1
These are discouraged, backward compatibility macros for "isALPHANUMERIC
". That is, each returns a boolean indicating whether the specified character is one of [A-Za-z0-9]
, analogous to m/[[:alnum:]]/
.
The C
suffix in the names was meant to indicate that they correspond to the C language isalnum(3)
.
bool isALNUMC(UV ch)
isALPHA
isALPHA_A
isALPHA_LC
isALPHA_LC_utf8_safe
isALPHA_LC_uvchr
isALPHA_L1
isALPHA_utf8
isALPHA_utf8_safe
isALPHA_uvchr
Returns a boolean indicating whether the specified input is one of [A-Za-z]
, analogous to m/[[:alpha:]]/
. See the top of this section for an explanation of the variants.
bool isALPHA (UV ch)
bool isALPHA_A (UV ch)
bool isALPHA_LC (UV ch)
bool isALPHA_LC_utf8_safe(U8 * s, U8 *end)
bool isALPHA_LC_uvchr (UV ch)
bool isALPHA_L1 (UV ch)
bool isALPHA_utf8 (U8 * s, U8 * end)
bool isALPHA_utf8_safe (U8 * s, U8 * end)
bool isALPHA_uvchr (UV ch)
isALPHANUMERIC
isALPHANUMERIC_A
isALPHANUMERIC_LC
isALPHANUMERIC_LC_utf8_safe
isALPHANUMERIC_LC_uvchr
isALPHANUMERIC_L1
isALPHANUMERIC_utf8
isALPHANUMERIC_utf8_safe
isALPHANUMERIC_uvchr
Returns a boolean indicating whether the specified character is one of [A-Za-z0-9]
, analogous to m/[[:alnum:]]/
. See the top of this section for an explanation of the variants.
bool isALPHANUMERIC (UV ch)
bool isALPHANUMERIC_A (UV ch)
bool isALPHANUMERIC_LC (UV ch)
bool isALPHANUMERIC_LC_utf8_safe(U8 * s, U8 *end)
bool isALPHANUMERIC_LC_uvchr (UV ch)
bool isALPHANUMERIC_L1 (UV ch)
bool isALPHANUMERIC_utf8 (U8 * s, U8 * end)
bool isALPHANUMERIC_utf8_safe (U8 * s, U8 * end)
bool isALPHANUMERIC_uvchr (UV ch)
isASCII
isASCII_A
isASCII_LC
isASCII_LC_utf8_safe
isASCII_LC_uvchr
isASCII_L1
isASCII_utf8
isASCII_utf8_safe
isASCII_uvchr
Returns a boolean indicating whether the specified character is one of the 128 characters in the ASCII character set, analogous to m/[[:ascii:]]/
. On non-ASCII platforms, it returns TRUE iff this character corresponds to an ASCII character. Variants isASCII_A()
and isASCII_L1()
are identical to isASCII()
. See the top of this section for an explanation of the variants. Note, however, that some platforms do not have the C library routine isascii()
. In these cases, the variants whose names contain LC
are the same as the corresponding ones without.
Also note, that because all ASCII characters are UTF-8 invariant (meaning they have the exact same representation (always a single byte) whether encoded in UTF-8 or not), isASCII
will give the correct results when called with any byte in any string encoded or not in UTF-8. And similarly isASCII_utf8
and isASCII_utf8_safe
will work properly on any string encoded or not in UTF-8.
bool isASCII (UV ch)
bool isASCII_A (UV ch)
bool isASCII_LC (UV ch)
bool isASCII_LC_utf8_safe(U8 * s, U8 *end)
bool isASCII_LC_uvchr (UV ch)
bool isASCII_L1 (UV ch)
bool isASCII_utf8 (U8 * s, U8 * end)
bool isASCII_utf8_safe (U8 * s, U8 * end)
bool isASCII_uvchr (UV ch)
isBLANK
isBLANK_A
isBLANK_LC
isBLANK_LC_utf8_safe
isBLANK_LC_uvchr
isBLANK_L1
isBLANK_utf8
isBLANK_utf8_safe
isBLANK_uvchr
Returns a boolean indicating whether the specified character is a character considered to be a blank, analogous to m/[[:blank:]]/
. See the top of this section for an explanation of the variants. Note, however, that some platforms do not have the C library routine isblank()
. In these cases, the variants whose names contain LC
are the same as the corresponding ones without.
bool isBLANK (UV ch)
bool isBLANK_A (UV ch)
bool isBLANK_LC (UV ch)
bool isBLANK_LC_utf8_safe(U8 * s, U8 *end)
bool isBLANK_LC_uvchr (UV ch)
bool isBLANK_L1 (UV ch)
bool isBLANK_utf8 (U8 * s, U8 * end)
bool isBLANK_utf8_safe (U8 * s, U8 * end)
bool isBLANK_uvchr (UV ch)
isCNTRL
isCNTRL_A
isCNTRL_LC
isCNTRL_LC_utf8_safe
isCNTRL_LC_uvchr
isCNTRL_L1
isCNTRL_utf8
isCNTRL_utf8_safe
isCNTRL_uvchr
Returns a boolean indicating whether the specified character is a control character, analogous to m/[[:cntrl:]]/
. See the top of this section for an explanation of the variants. On EBCDIC platforms, you almost always want to use the isCNTRL_L1
variant.
bool isCNTRL (UV ch)
bool isCNTRL_A (UV ch)
bool isCNTRL_LC (UV ch)
bool isCNTRL_LC_utf8_safe(U8 * s, U8 *end)
bool isCNTRL_LC_uvchr (UV ch)
bool isCNTRL_L1 (UV ch)
bool isCNTRL_utf8 (U8 * s, U8 * end)
bool isCNTRL_utf8_safe (U8 * s, U8 * end)
bool isCNTRL_uvchr (UV ch)
isDIGIT
isDIGIT_A
isDIGIT_LC
isDIGIT_LC_utf8_safe
isDIGIT_LC_uvchr
isDIGIT_L1
isDIGIT_utf8
isDIGIT_utf8_safe
isDIGIT_uvchr
Returns a boolean indicating whether the specified character is a digit, analogous to m/[[:digit:]]/
. Variants isDIGIT_A
and isDIGIT_L1
are identical to isDIGIT
. See the top of this section for an explanation of the variants.
bool isDIGIT (UV ch)
bool isDIGIT_A (UV ch)
bool isDIGIT_LC (UV ch)
bool isDIGIT_LC_utf8_safe(U8 * s, U8 *end)
bool isDIGIT_LC_uvchr (UV ch)
bool isDIGIT_L1 (UV ch)
bool isDIGIT_utf8 (U8 * s, U8 * end)
bool isDIGIT_utf8_safe (U8 * s, U8 * end)
bool isDIGIT_uvchr (UV ch)
isGRAPH
isGRAPH_A
isGRAPH_LC
isGRAPH_LC_utf8_safe
isGRAPH_LC_uvchr
isGRAPH_L1
isGRAPH_utf8
isGRAPH_utf8_safe
isGRAPH_uvchr
Returns a boolean indicating whether the specified character is a graphic character, analogous to m/[[:graph:]]/
. See the top of this section for an explanation of the variants.
bool isGRAPH (UV ch)
bool isGRAPH_A (UV ch)
bool isGRAPH_LC (UV ch)
bool isGRAPH_LC_utf8_safe(U8 * s, U8 *end)
bool isGRAPH_LC_uvchr (UV ch)
bool isGRAPH_L1 (UV ch)
bool isGRAPH_utf8 (U8 * s, U8 * end)
bool isGRAPH_utf8_safe (U8 * s, U8 * end)
bool isGRAPH_uvchr (UV ch)
isIDCONT
isIDCONT_A
isIDCONT_LC
isIDCONT_LC_utf8_safe
isIDCONT_LC_uvchr
isIDCONT_L1
isIDCONT_utf8
isIDCONT_utf8_safe
isIDCONT_uvchr
Returns a boolean indicating whether the specified character can be the second or succeeding character of an identifier. This is very close to, but not quite the same as the official Unicode property XID_Continue
. The difference is that this returns true only if the input character also matches "isWORDCHAR". See the top of this section for an explanation of the variants.
bool isIDCONT (UV ch)
bool isIDCONT_A (UV ch)
bool isIDCONT_LC (UV ch)
bool isIDCONT_LC_utf8_safe(U8 * s, U8 *end)
bool isIDCONT_LC_uvchr (UV ch)
bool isIDCONT_L1 (UV ch)
bool isIDCONT_utf8 (U8 * s, U8 * end)
bool isIDCONT_utf8_safe (U8 * s, U8 * end)
bool isIDCONT_uvchr (UV ch)
isIDFIRST
isIDFIRST_A
isIDFIRST_LC
isIDFIRST_LC_utf8_safe
isIDFIRST_LC_uvchr
isIDFIRST_L1
isIDFIRST_utf8
isIDFIRST_utf8_safe
isIDFIRST_uvchr
Returns a boolean indicating whether the specified character can be the first character of an identifier. This is very close to, but not quite the same as the official Unicode property XID_Start
. The difference is that this returns true only if the input character also matches "isWORDCHAR". See the top of this section for an explanation of the variants.
bool isIDFIRST (UV ch)
bool isIDFIRST_A (UV ch)
bool isIDFIRST_LC (UV ch)
bool isIDFIRST_LC_utf8_safe(U8 * s, U8 *end)
bool isIDFIRST_LC_uvchr (UV ch)
bool isIDFIRST_L1 (UV ch)
bool isIDFIRST_utf8 (U8 * s, U8 * end)
bool isIDFIRST_utf8_safe (U8 * s, U8 * end)
bool isIDFIRST_uvchr (UV ch)
isLOWER
isLOWER_A
isLOWER_LC
isLOWER_LC_utf8_safe
isLOWER_LC_uvchr
isLOWER_L1
isLOWER_utf8
isLOWER_utf8_safe
isLOWER_uvchr
Returns a boolean indicating whether the specified character is a lowercase character, analogous to m/[[:lower:]]/
. See the top of this section for an explanation of the variants
bool isLOWER (UV ch)
bool isLOWER_A (UV ch)
bool isLOWER_LC (UV ch)
bool isLOWER_LC_utf8_safe(U8 * s, U8 *end)
bool isLOWER_LC_uvchr (UV ch)
bool isLOWER_L1 (UV ch)
bool isLOWER_utf8 (U8 * s, U8 * end)
bool isLOWER_utf8_safe (U8 * s, U8 * end)
bool isLOWER_uvchr (UV ch)
isOCTAL
isOCTAL_A
isOCTAL_L1
Returns a boolean indicating whether the specified character is an octal digit, [0-7]. The only two variants are isOCTAL_A
and isOCTAL_L1
; each is identical to isOCTAL
.
bool isOCTAL(UV ch)
isPRINT
isPRINT_A
isPRINT_LC
isPRINT_LC_utf8_safe
isPRINT_LC_uvchr
isPRINT_L1
isPRINT_utf8
isPRINT_utf8_safe
isPRINT_uvchr
Returns a boolean indicating whether the specified character is a printable character, analogous to m/[[:print:]]/
. See the top of this section for an explanation of the variants.
bool isPRINT (UV ch)
bool isPRINT_A (UV ch)
bool isPRINT_LC (UV ch)
bool isPRINT_LC_utf8_safe(U8 * s, U8 *end)
bool isPRINT_LC_uvchr (UV ch)
bool isPRINT_L1 (UV ch)
bool isPRINT_utf8 (U8 * s, U8 * end)
bool isPRINT_utf8_safe (U8 * s, U8 * end)
bool isPRINT_uvchr (UV ch)
isPSXSPC
isPSXSPC_A
isPSXSPC_LC
isPSXSPC_LC_utf8_safe
isPSXSPC_LC_uvchr
isPSXSPC_L1
isPSXSPC_utf8
isPSXSPC_utf8_safe
isPSXSPC_uvchr
(short for Posix Space) Starting in 5.18, this is identical in all its forms to the corresponding isSPACE()
macros. The locale forms of this macro are identical to their corresponding isSPACE()
forms in all Perl releases. In releases prior to 5.18, the non-locale forms differ from their isSPACE()
forms only in that the isSPACE()
forms don't match a Vertical Tab, and the isPSXSPC()
forms do. Otherwise they are identical. Thus this macro is analogous to what m/[[:space:]]/
matches in a regular expression. See the top of this section for an explanation of the variants.
bool isPSXSPC (UV ch)
bool isPSXSPC_A (UV ch)
bool isPSXSPC_LC (UV ch)
bool isPSXSPC_LC_utf8_safe(U8 * s, U8 *end)
bool isPSXSPC_LC_uvchr (UV ch)
bool isPSXSPC_L1 (UV ch)
bool isPSXSPC_utf8 (U8 * s, U8 * end)
bool isPSXSPC_utf8_safe (U8 * s, U8 * end)
bool isPSXSPC_uvchr (UV ch)
isPUNCT
isPUNCT_A
isPUNCT_LC
isPUNCT_LC_utf8_safe
isPUNCT_LC_uvchr
isPUNCT_L1
isPUNCT_utf8
isPUNCT_utf8_safe
isPUNCT_uvchr
Returns a boolean indicating whether the specified character is a punctuation character, analogous to m/[[:punct:]]/
. Note that the definition of what is punctuation isn't as straightforward as one might desire. See "POSIX Character Classes" in perlrecharclass for details. See the top of this section for an explanation of the variants.
bool isPUNCT (UV ch)
bool isPUNCT_A (UV ch)
bool isPUNCT_LC (UV ch)
bool isPUNCT_LC_utf8_safe(U8 * s, U8 *end)
bool isPUNCT_LC_uvchr (UV ch)
bool isPUNCT_L1 (UV ch)
bool isPUNCT_utf8 (U8 * s, U8 * end)
bool isPUNCT_utf8_safe (U8 * s, U8 * end)
bool isPUNCT_uvchr (UV ch)
isSPACE
isSPACE_A
isSPACE_LC
isSPACE_LC_utf8_safe
isSPACE_LC_uvchr
isSPACE_L1
isSPACE_utf8
isSPACE_utf8_safe
isSPACE_uvchr
Returns a boolean indicating whether the specified character is a whitespace character. This is analogous to what m/\s/
matches in a regular expression. Starting in Perl 5.18 this also matches what m/[[:space:]]/
does. Prior to 5.18, only the locale forms of this macro (the ones with LC
in their names) matched precisely what m/[[:space:]]/
does. In those releases, the only difference, in the non-locale variants, was that isSPACE()
did not match a vertical tab. (See "isPSXSPC" for a macro that matches a vertical tab in all releases.) See the top of this section for an explanation of the variants.
bool isSPACE (UV ch)
bool isSPACE_A (UV ch)
bool isSPACE_LC (UV ch)
bool isSPACE_LC_utf8_safe(U8 * s, U8 *end)
bool isSPACE_LC_uvchr (UV ch)
bool isSPACE_L1 (UV ch)
bool isSPACE_utf8 (U8 * s, U8 * end)
bool isSPACE_utf8_safe (U8 * s, U8 * end)
bool isSPACE_uvchr (UV ch)
isUPPER
isUPPER_A
isUPPER_LC
isUPPER_LC_utf8_safe
isUPPER_LC_uvchr
isUPPER_L1
isUPPER_utf8
isUPPER_utf8_safe
isUPPER_uvchr
Returns a boolean indicating whether the specified character is an uppercase character, analogous to m/[[:upper:]]/
. See the top of this section for an explanation of the variants.
bool isUPPER (UV ch)
bool isUPPER_A (UV ch)
bool isUPPER_LC (UV ch)
bool isUPPER_LC_utf8_safe(U8 * s, U8 *end)
bool isUPPER_LC_uvchr (UV ch)
bool isUPPER_L1 (UV ch)
bool isUPPER_utf8 (U8 * s, U8 * end)
bool isUPPER_utf8_safe (U8 * s, U8 * end)
bool isUPPER_uvchr (UV ch)
isWORDCHAR
isWORDCHAR_A
isWORDCHAR_LC
isWORDCHAR_LC_utf8_safe
isWORDCHAR_LC_uvchr
isWORDCHAR_L1
isWORDCHAR_utf8
isWORDCHAR_utf8_safe
isWORDCHAR_uvchr
Returns a boolean indicating whether the specified character is a character that is a word character, analogous to what m/\w/
and m/[[:word:]]/
match in a regular expression. A word character is an alphabetic character, a decimal digit, a connecting punctuation character (such as an underscore), or a "mark" character that attaches to one of those (like some sort of accent).
See the top of this section for an explanation of the variants.
isWORDCHAR_A
, isWORDCHAR_L1
, isWORDCHAR_uvchr
, isWORDCHAR_LC
, isWORDCHAR_LC_uvchr
, isWORDCHAR_LC_utf8
, and isWORDCHAR_LC_utf8_safe
are also as described there, but additionally include the platform's native underscore.
bool isWORDCHAR (UV ch)
bool isWORDCHAR_A (UV ch)
bool isWORDCHAR_LC (UV ch)
bool isWORDCHAR_LC_utf8_safe(U8 * s, U8 *end)
bool isWORDCHAR_LC_uvchr (UV ch)
bool isWORDCHAR_L1 (UV ch)
bool isWORDCHAR_utf8 (U8 * s, U8 * end)
bool isWORDCHAR_utf8_safe (U8 * s, U8 * end)
bool isWORDCHAR_uvchr (UV ch)
isXDIGIT
isXDIGIT_A
isXDIGIT_LC
isXDIGIT_LC_utf8_safe
isXDIGIT_LC_uvchr
isXDIGIT_L1
isXDIGIT_utf8
isXDIGIT_utf8_safe
isXDIGIT_uvchr
Returns a boolean indicating whether the specified character is a hexadecimal digit. In the ASCII range these are [0-9A-Fa-f]
. Variants isXDIGIT_A()
and isXDIGIT_L1()
are identical to isXDIGIT()
. See the top of this section for an explanation of the variants.
bool isXDIGIT (UV ch)
bool isXDIGIT_A (UV ch)
bool isXDIGIT_LC (UV ch)
bool isXDIGIT_LC_utf8_safe(U8 * s, U8 *end)
bool isXDIGIT_LC_uvchr (UV ch)
bool isXDIGIT_L1 (UV ch)
bool isXDIGIT_utf8 (U8 * s, U8 * end)
bool isXDIGIT_utf8_safe (U8 * s, U8 * end)
bool isXDIGIT_uvchr (UV ch)
CPPLAST
This symbol is intended to be used along with CPPRUN
in the same manner symbol CPPMINUS
is used with CPPSTDIN
. It contains either "-" or "".
CPPMINUS
This symbol contains the second part of the string which will invoke the C preprocessor on the standard input and produce to standard output. This symbol will have the value "-" if CPPSTDIN
needs a minus to specify standard input, otherwise the value is "".
CPPRUN
This symbol contains the string which will invoke a C preprocessor on the standard input and produce to standard output. It needs to end with CPPLAST
, after all other preprocessor flags have been specified. The main difference with CPPSTDIN
is that this program will never be a pointer to a shell wrapper, i.e. it will be empty if no preprocessor is available directly to the user. Note that it may well be different from the preprocessor used to compile the C program.
CPPSTDIN
This symbol contains the first part of the string which will invoke the C preprocessor on the standard input and produce to standard output. Typical value of "cc -E" or "/lib/cpp", but it can also call a wrapper. See "CPPRUN"
.
HASATTRIBUTE_ALWAYS_INLINE
Can we handle GCC
attribute for functions that should always be inlined.
HASATTRIBUTE_DEPRECATED
Can we handle GCC
attribute for marking deprecated APIs
HASATTRIBUTE_FORMAT
Can we handle GCC
attribute for checking printf-style formats
HASATTRIBUTE_NONNULL
Can we handle GCC
attribute for nonnull function parms.
HASATTRIBUTE_NORETURN
Can we handle GCC
attribute for functions that do not return
HASATTRIBUTE_PURE
Can we handle GCC
attribute for pure functions
HASATTRIBUTE_UNUSED
Can we handle GCC
attribute for unused variables and arguments
HASATTRIBUTE_VISIBILITY
Can we handle GCC
attribute for functions that should have a different visibility.
HASATTRIBUTE_WARN_UNUSED_RESULT
Can we handle GCC
attribute for warning on unused results
HAS_BUILTIN_ADD_OVERFLOW
This symbol, if defined, indicates that the compiler supports __builtin_add_overflow
for adding integers with overflow checks.
HAS_BUILTIN_CHOOSE_EXPR
Can we handle GCC
builtin for compile-time ternary-like expressions
HAS_BUILTIN_EXPECT
Can we handle GCC
builtin for telling that certain values are more likely
HAS_BUILTIN_MUL_OVERFLOW
This symbol, if defined, indicates that the compiler supports __builtin_mul_overflow
for multiplying integers with overflow checks.
HAS_BUILTIN_SUB_OVERFLOW
This symbol, if defined, indicates that the compiler supports __builtin_sub_overflow
for subtracting integers with overflow checks.
HAS_C99_VARIADIC_MACROS
If defined, the compiler supports C99 variadic macros.
HAS_STATIC_INLINE
This symbol, if defined, indicates that the C compiler supports C99-style static inline. That is, the function can't be called from another translation unit.
MEM_ALIGNBYTES
This symbol contains the number of bytes required to align a double, or a long double when applicable. Usual values are 2, 4 and 8. The default is eight, for safety. For cross-compiling or multiarch support, Configure will set a minimum of 8.
PERL_STATIC_INLINE
This symbol gives the best-guess incantation to use for static inline functions. If HAS_STATIC_INLINE
is defined, this will give C99-style inline. If HAS_STATIC_INLINE
is not defined, this will give a plain 'static'. It will always be defined to something that gives static linkage. Possibilities include
static inline (c99)
static __inline__ (gcc -ansi)
static __inline (MSVC)
static _inline (older MSVC)
static (c89 compilers)
PERL_THREAD_LOCAL
This symbol, if defined, gives a linkage specification for thread-local storage. For example, for a C11 compiler this will be _Thread_local
. Beware, some compilers are sensitive to the C language standard they are told to parse. For example, suncc defaults to C11, so our probe will report that _Thread_local
can be used. However, if the -std=c99 is later added to the compiler flags, then _Thread_local
will become a syntax error. Hence it is important for these flags to be consistent between probing and use.
U32_ALIGNMENT_REQUIRED
This symbol, if defined, indicates that you must access character data through U32-aligned pointers.
__ASSERT_
This is a helper macro to avoid preprocessor issues, replaced by nothing unless under DEBUGGING, where it expands to an assert of its argument, followed by a comma (hence the comma operator). If we just used a straight assert(), we would get a comma with nothing before it when not DEBUGGING.
__ASSERT_(bool expr)
ASSUME
ASSUME
is like assert()
, but it has a benefit in a release build. It is a hint to a compiler about a statement of fact in a function call free expression, which allows the compiler to generate better machine code. In a debug build, ASSUME(x)
is a synonym for assert(x)
. ASSUME(0)
means the control path is unreachable. In a for loop, ASSUME
can be used to hint that a loop will run at least X times. ASSUME
is based off MSVC's __assume
intrinsic function, see its documents for more details.
ASSUME(bool expr)
dNOOP
Declare nothing; typically used as a placeholder to replace something that used to declare something. Works on compilers that require declarations before any code.
dNOOP;
END_EXTERN_C
When not compiling using C++, expands to nothing. Otherwise ends a section of code already begun by a "START_EXTERN_C"
.
END_EXTERN_C
EXTERN_C
When not compiling using C++, expands to nothing. Otherwise is used in a declaration of a function to indicate the function should have external C linkage. This is required for things to work for just about all functions with external linkage compiled into perl. Often, you can use "START_EXTERN_C"
... "END_EXTERN_C"
blocks surrounding all your code that you need to have this linkage.
Example usage:
EXTERN_C int flock(int fd, int op);
LIKELY
Returns the input unchanged, but at the same time it gives a branch prediction hint to the compiler that this condition is likely to be true.
LIKELY(bool expr)
NOOP
Do nothing; typically used as a placeholder to replace something that used to do something.
NOOP;
PERL_UNUSED_ARG
This is used to suppress compiler warnings that a parameter to a function is not used. This situation can arise, for example, when a parameter is needed under some configuration conditions, but not others, so that C preprocessor conditional compilation causes it be used just sometimes.
PERL_UNUSED_ARG(void x);
PERL_UNUSED_CONTEXT
This is used to suppress compiler warnings that the thread context parameter to a function is not used. This situation can arise, for example, when a C preprocessor conditional compilation causes it be used just some times.
PERL_UNUSED_CONTEXT;
PERL_UNUSED_DECL
Tells the compiler that the parameter in the function prototype just before it is not necessarily expected to be used in the function. Not that many compilers understand this, so this should only be used in cases where "PERL_UNUSED_ARG"
can't conveniently be used.
Example usage:
Signal_t
Perl_perly_sighandler(int sig, Siginfo_t *sip PERL_UNUSED_DECL,
void *uap PERL_UNUSED_DECL, bool safe)
PERL_UNUSED_RESULT
This macro indicates to discard the return value of the function call inside it, e.g.,
PERL_UNUSED_RESULT(foo(a, b))
The main reason for this is that the combination of gcc -Wunused-result
(part of -Wall
) and the __attribute__((warn_unused_result))
cannot be silenced with casting to void
. This causes trouble when the system header files use the attribute.
Use PERL_UNUSED_RESULT
sparingly, though, since usually the warning is there for a good reason: you might lose success/failure information, or leak resources, or changes in resources.
But sometimes you just want to ignore the return value, e.g., on codepaths soon ending up in abort, or in "best effort" attempts, or in situations where there is no good way to handle failures.
Sometimes PERL_UNUSED_RESULT
might not be the most natural way: another possibility is that you can capture the return value and use "PERL_UNUSED_VAR"
on that.
PERL_UNUSED_RESULT(void x)
PERL_UNUSED_VAR
This is used to suppress compiler warnings that the variable x is not used. This situation can arise, for example, when a C preprocessor conditional compilation causes it be used just some times.
PERL_UNUSED_VAR(void x);
START_EXTERN_C
When not compiling using C++, expands to nothing. Otherwise begins a section of code in which every function will effectively have "EXTERN_C"
applied to it, that is to have external C linkage. The section is ended by a "END_EXTERN_C"
.
START_EXTERN_C
STMT_END
STMT_START
These allow a series of statements in a macro to be used as a single statement, as in
if (x) STMT_START { ... } STMT_END else ...
Note that you can't return a value out of this construct and cannot use it as an operand to the comma operator. These limit its utility.
But, a value could be returned by constructing the API so that a pointer is passed and the macro dereferences this to set the return. If the value can be any of various types, depending on context, you can handle that situation in some situations by adding the type of the return as an extra accompanying parameter:
#define foo(param, type) STMT_START {
type * param; *param = do_calc; ...
} STMT_END
This could be awkward, so consider instead using a C language static inline
function.
If you do use this construct, it is easy to forget that it is a macro and not a function, and hence fall into traps that might not show up until someone someday writes code which contains names that clash with the ones you chose here, or calls it with a parameter which is an expression with side effects, the consequences of which you didn't think about. See "Writing safer macros" in perlhacktips for how to avoid these.
UNLIKELY
Returns the input unchanged, but at the same time it gives a branch prediction hint to the compiler that this condition is likely to be false.
UNLIKELY(bool expr)
BhkDISABLE
NOTE: BhkDISABLE
is experimental and may change or be removed without notice.
Temporarily disable an entry in this BHK structure, by clearing the appropriate flag. which
is a preprocessor token indicating which entry to disable.
void BhkDISABLE(BHK *hk, token which)
BhkENABLE
NOTE: BhkENABLE
is experimental and may change or be removed without notice.
Re-enable an entry in this BHK structure, by setting the appropriate flag. which
is a preprocessor token indicating which entry to enable. This will assert (under -DDEBUGGING) if the entry doesn't contain a valid pointer.
void BhkENABLE(BHK *hk, token which)
BhkENTRY_set
NOTE: BhkENTRY_set
is experimental and may change or be removed without notice.
Set an entry in the BHK structure, and set the flags to indicate it is valid. which
is a preprocessing token indicating which entry to set. The type of ptr
depends on the entry.
void BhkENTRY_set(BHK *hk, token which, void *ptr)
blockhook_register
NOTE: blockhook_register
is experimental and may change or be removed without notice.
Register a set of hooks to be called when the Perl lexical scope changes at compile time. See "Compile-time scope hooks" in perlguts.
NOTE: blockhook_register
must be explicitly called as Perl_blockhook_register
with an aTHX_
parameter.
void Perl_blockhook_register(pTHX_ BHK *hk)
CPERLscope
DEPRECATED!
It is planned to remove CPERLscope
from a future release of Perl. Do not use it for new code; remove it from existing code.
Now a no-op.
void CPERLscope(void x)
dTHXa
On threaded perls, set pTHX
to a
; on unthreaded perls, do nothing
dVAR
This is now a synonym for dNOOP: declare nothing
GETENV_PRESERVES_OTHER_THREAD
This symbol, if defined, indicates that the getenv system call doesn't zap the static buffer of getenv()
in a different thread. The typical getenv()
implementation will return a pointer to the proper position in **environ. But some may instead copy them to a static buffer in getenv()
. If there is a per-thread instance of that buffer, or the return points to **environ, then a many-reader/1-writer mutex will work; otherwise an exclusive locking mutex is required to prevent races.
HAS_PTHREAD_ATFORK
This symbol, if defined, indicates that the pthread_atfork
routine is available to setup fork handlers.
HAS_PTHREAD_ATTR_SETSCOPE
This symbol, if defined, indicates that the pthread_attr_setscope
system call is available to set the contention scope attribute of a thread attribute object.
HAS_PTHREAD_YIELD
This symbol, if defined, indicates that the pthread_yield
routine is available to yield the execution of the current thread. sched_yield
is preferable to pthread_yield
.
HAS_SCHED_YIELD
This symbol, if defined, indicates that the sched_yield
routine is available to yield the execution of the current thread. sched_yield
is preferable to pthread_yield
.
I_MACH_CTHREADS
This symbol, if defined, indicates to the C program that it should include mach/cthreads.h.
#ifdef I_MACH_CTHREADS
#include <mach_cthreads.h>
#endif
I_PTHREAD
This symbol, if defined, indicates to the C program that it should include pthread.h.
#ifdef I_PTHREAD
#include <pthread.h>
#endif
MULTIPLICITY
This symbol, if defined, indicates that Perl should be built to use multiplicity.
OLD_PTHREAD_CREATE_JOINABLE
This symbol, if defined, indicates how to create pthread in joinable (aka undetached) state. NOTE
: not defined if pthread.h already has defined PTHREAD_CREATE_JOINABLE
(the new version of the constant). If defined, known values are PTHREAD_CREATE_UNDETACHED
and __UNDETACHED
.
OLD_PTHREADS_API
This symbol, if defined, indicates that Perl should be built to use the old draft POSIX
threads API
.
SCHED_YIELD
This symbol defines the way to yield the execution of the current thread. Known ways are sched_yield
, pthread_yield
, and pthread_yield
with NULL
.
cop_fetch_label
NOTE: cop_fetch_label
is experimental and may change or be removed without notice.
Returns the label attached to a cop, and stores its length in bytes into *len
. Upon return, *flags
will be set to either SVf_UTF8
or 0.
Alternatively, use the macro "CopLABEL_len_flags"
; or if you don't need to know if the label is UTF-8 or not, the macro "CopLABEL_len"
; or if you additionally don't need to know the length, "CopLABEL"
.
const char * cop_fetch_label(COP * const cop, STRLEN *len,
U32 *flags)
CopFILE
Returns the name of the file associated with the COP
c
const char * CopFILE(const COP * c)
CopFILEAV
Returns the AV associated with the COP
c
, creating it if necessary.
AV * CopFILEAV(const COP * c)
CopFILEAVn
Returns the AV associated with the COP
c
, returning NULL if it doesn't already exist.
AV * CopFILEAVn(const COP * c)
CopFILE_copy
Efficiently copies the cop file name from one COP to another. Wraps the required logic to do a refcounted copy under threads or not.
void CopFILE_copy(COP * dst, COP * src)
CopFILE_free
Frees the file data in a cop. Under the hood this is a refcounting operation.
void CopFILE_free(COP * c)
CopFILEGV
Returns the GV associated with the COP
c
GV * CopFILEGV(const COP * c)
CopFILEGV_set
Available only on unthreaded perls. Makes pv
the name of the file associated with the COP
c
void CopFILEGV_set(COP *c, GV *gv)
CopFILE_LEN
Returns the length of the file associated with the COP
c
const char * CopFILE_LEN(const COP * c)
CopFILE_set
Makes pv
the name of the file associated with the COP
c
void CopFILE_set(COP * c, const char * pv)
CopFILE_setn
Makes pv
the name of the file associated with the COP
c
void CopFILE_setn(COP * c, const char * pv, STRLEN len)
CopFILESV
Returns the SV associated with the COP
c
SV * CopFILESV(const COP * c)
cophh_copy
NOTE: cophh_copy
is experimental and may change or be removed without notice.
Make and return a complete copy of the cop hints hash cophh
.
COPHH * cophh_copy(COPHH *cophh)
cophh_delete_pv
cophh_delete_pvn
cophh_delete_pvs
cophh_delete_sv
NOTE: all these forms are experimental and may change or be removed without notice.
These delete a key and its associated value from the cop hints hash cophh
, and return the modified hash. The returned hash pointer is in general not the same as the hash pointer that was passed in. The input hash is consumed by the function, and the pointer to it must not be subsequently used. Use "cophh_copy" if you need both hashes.
The forms differ in how the key is specified. In all forms, the key is pointed to by key
. In the plain pv
form, the key is a C language NUL-terminated string. In the pvs
form, the key is a C language string literal. In the pvn
form, an additional parameter, keylen
, specifies the length of the string, which hence, may contain embedded-NUL characters. In the sv
form, *key
is an SV, and the key is the PV extracted from that. using "SvPV_const"
.
hash
is a precomputed hash of the key string, or zero if it has not been precomputed. This parameter is omitted from the pvs
form, as it is computed automatically at compile time.
The only flag currently used from the flags
parameter is COPHH_KEY_UTF8
. It is illegal to set this in the sv
form. In the pv*
forms, it specifies whether the key octets are interpreted as UTF-8 (if set) or as Latin-1 (if cleared). The sv
form uses the underlying SV to determine the UTF-8ness of the octets.
COPHH * cophh_delete_pv (COPHH *cophh, const char *key, U32 hash,
U32 flags)
COPHH * cophh_delete_pvn(COPHH *cophh, const char *key,
STRLEN keylen, U32 hash, U32 flags)
COPHH * cophh_delete_pvs(COPHH *cophh, "key", U32 flags)
COPHH * cophh_delete_sv (COPHH *cophh, SV *key, U32 hash,
U32 flags)
cophh_exists_pvn
NOTE: cophh_exists_pvn
is experimental and may change or be removed without notice.
These look up the hint entry in the cop cop
with the key specified by key
(and keylen
in the pvn
form), returning true if a value exists, and false otherwise.
The forms differ in how the key is specified. In the plain pv
form, the key is a C language NUL-terminated string. In the pvs
form, the key is a C language string literal. In the pvn
form, an additional parameter, keylen
, specifies the length of the string, which hence, may contain embedded-NUL characters. In the sv
form, *key
is an SV, and the key is the PV extracted from that. using "SvPV_const"
.
hash
is a precomputed hash of the key string, or zero if it has not been precomputed. This parameter is omitted from the pvs
form, as it is computed automatically at compile time.
The only flag currently used from the flags
parameter is COPHH_KEY_UTF8
. It is illegal to set this in the sv
form. In the pv*
forms, it specifies whether the key octets are interpreted as UTF-8 (if set) or as Latin-1 (if cleared). The sv
form uses the underlying SV to determine the UTF-8ness of the octets.
bool cophh_exists_pvn(const COPHH *cophh, const char *key,
STRLEN keylen, U32 hash, U32 flags)
cophh_fetch_pv
cophh_fetch_pvn
cophh_fetch_pvs
cophh_fetch_sv
NOTE: all these forms are experimental and may change or be removed without notice.
These look up the entry in the cop hints hash cophh
with the key specified by key
(and keylen
in the pvn
form), returning that value as a mortal scalar copy, or &PL_sv_placeholder
if there is no value associated with the key.
The forms differ in how the key is specified. In the plain pv
form, the key is a C language NUL-terminated string. In the pvs
form, the key is a C language string literal. In the pvn
form, an additional parameter, keylen
, specifies the length of the string, which hence, may contain embedded-NUL characters. In the sv
form, *key
is an SV, and the key is the PV extracted from that. using "SvPV_const"
.
hash
is a precomputed hash of the key string, or zero if it has not been precomputed. This parameter is omitted from the pvs
form, as it is computed automatically at compile time.
The only flag currently used from the flags
parameter is COPHH_KEY_UTF8
. It is illegal to set this in the sv
form. In the pv*
forms, it specifies whether the key octets are interpreted as UTF-8 (if set) or as Latin-1 (if cleared). The sv
form uses the underlying SV to determine the UTF-8ness of the octets.
SV * cophh_fetch_pv (const COPHH *cophh, const char *key,
U32 hash, U32 flags)
SV * cophh_fetch_pvn(const COPHH *cophh, const char *key,
STRLEN keylen, U32 hash, U32 flags)
SV * cophh_fetch_pvs(const COPHH *cophh, "key", U32 flags)
SV * cophh_fetch_sv (const COPHH *cophh, SV *key, U32 hash,
U32 flags)
cophh_free
NOTE: cophh_free
is experimental and may change or be removed without notice.
Discard the cop hints hash cophh
, freeing all resources associated with it.
void cophh_free(COPHH *cophh)
cophh_2hv
NOTE: cophh_2hv
is experimental and may change or be removed without notice.
Generates and returns a standard Perl hash representing the full set of key/value pairs in the cop hints hash cophh
. flags
is currently unused and must be zero.
HV * cophh_2hv(const COPHH *cophh, U32 flags)
cophh_new_empty
NOTE: cophh_new_empty
is experimental and may change or be removed without notice.
Generate and return a fresh cop hints hash containing no entries.
COPHH * cophh_new_empty()
cophh_store_pv
cophh_store_pvn
cophh_store_pvs
cophh_store_sv
NOTE: all these forms are experimental and may change or be removed without notice.
These store a value, associated with a key, in the cop hints hash cophh
, and return the modified hash. The returned hash pointer is in general not the same as the hash pointer that was passed in. The input hash is consumed by the function, and the pointer to it must not be subsequently used. Use "cophh_copy" if you need both hashes.
value
is the scalar value to store for this key. value
is copied by these functions, which thus do not take ownership of any reference to it, and hence later changes to the scalar will not be reflected in the value visible in the cop hints hash. Complex types of scalar will not be stored with referential integrity, but will be coerced to strings.
The forms differ in how the key is specified. In all forms, the key is pointed to by key
. In the plain pv
form, the key is a C language NUL-terminated string. In the pvs
form, the key is a C language string literal. In the pvn
form, an additional parameter, keylen
, specifies the length of the string, which hence, may contain embedded-NUL characters. In the sv
form, *key
is an SV, and the key is the PV extracted from that. using "SvPV_const"
.
hash
is a precomputed hash of the key string, or zero if it has not been precomputed. This parameter is omitted from the pvs
form, as it is computed automatically at compile time.
The only flag currently used from the flags
parameter is COPHH_KEY_UTF8
. It is illegal to set this in the sv
form. In the pv*
forms, it specifies whether the key octets are interpreted as UTF-8 (if set) or as Latin-1 (if cleared). The sv
form uses the underlying SV to determine the UTF-8ness of the octets.
COPHH * cophh_store_pv (COPHH *cophh, const char *key, U32 hash,
SV *value, U32 flags)
COPHH * cophh_store_pvn(COPHH *cophh, const char *key,
STRLEN keylen, U32 hash, SV *value,
U32 flags)
COPHH * cophh_store_pvs(COPHH *cophh, "key", SV *value,
U32 flags)
COPHH * cophh_store_sv (COPHH *cophh, SV *key, U32 hash,
SV *value, U32 flags)
cop_hints_exists_pv
cop_hints_exists_pvn
cop_hints_exists_pvs
cop_hints_exists_sv
These look up the hint entry in the cop cop
with the key specified by key
(and keylen
in the pvn
form), returning true if a value exists, and false otherwise.
The forms differ in how the key is specified. In all forms, the key is pointed to by key
. In the plain pv
form, the key is a C language NUL-terminated string. In the pvs
form, the key is a C language string literal. In the pvn
form, an additional parameter, keylen
, specifies the length of the string, which hence, may contain embedded-NUL characters. In the sv
form, *key
is an SV, and the key is the PV extracted from that. using "SvPV_const"
.
hash
is a precomputed hash of the key string, or zero if it has not been precomputed. This parameter is omitted from the pvs
form, as it is computed automatically at compile time.
The only flag currently used from the flags
parameter is COPHH_KEY_UTF8
. It is illegal to set this in the sv
form. In the pv*
forms, it specifies whether the key octets are interpreted as UTF-8 (if set) or as Latin-1 (if cleared). The sv
form uses the underlying SV to determine the UTF-8ness of the octets.
bool cop_hints_exists_pv (const COP *cop, const char *key,
U32 hash, U32 flags)
bool cop_hints_exists_pvn(const COP *cop, const char *key,
STRLEN keylen, U32 hash, U32 flags)
bool cop_hints_exists_pvs(const COP *cop, "key", U32 flags)
bool cop_hints_exists_sv (const COP *cop, SV *key, U32 hash,
U32 flags)
cop_hints_fetch_pv
cop_hints_fetch_pvn
cop_hints_fetch_pvs
cop_hints_fetch_sv
These look up the hint entry in the cop cop
with the key specified by key
(and keylen
in the pvn
form), returning that value as a mortal scalar copy, or &PL_sv_placeholder
if there is no value associated with the key.
The forms differ in how the key is specified. In the plain pv
form, the key is a C language NUL-terminated string. In the pvs
form, the key is a C language string literal. In the pvn
form, an additional parameter, keylen
, specifies the length of the string, which hence, may contain embedded-NUL characters. In the sv
form, *key
is an SV, and the key is the PV extracted from that. using "SvPV_const"
.
hash
is a precomputed hash of the key string, or zero if it has not been precomputed. This parameter is omitted from the pvs
form, as it is computed automatically at compile time.
The only flag currently used from the flags
parameter is COPHH_KEY_UTF8
. It is illegal to set this in the sv
form. In the pv*
forms, it specifies whether the key octets are interpreted as UTF-8 (if set) or as Latin-1 (if cleared). The sv
form uses the underlying SV to determine the UTF-8ness of the octets.
SV * cop_hints_fetch_pv (const COP *cop, const char *key,
U32 hash, U32 flags)
SV * cop_hints_fetch_pvn(const COP *cop, const char *key,
STRLEN keylen, U32 hash, U32 flags)
SV * cop_hints_fetch_pvs(const COP *cop, "key", U32 flags)
SV * cop_hints_fetch_sv (const COP *cop, SV *key, U32 hash,
U32 flags)
cop_hints_2hv
Generates and returns a standard Perl hash representing the full set of hint entries in the cop cop
. flags
is currently unused and must be zero.
HV * cop_hints_2hv(const COP *cop, U32 flags)
CopLABEL
CopLABEL_len
CopLABEL_len_flags
These return the label attached to a cop.
CopLABEL_len
and CopLABEL_len_flags
additionally store the number of bytes comprising the returned label into *len
.
CopLABEL_len_flags
additionally returns the UTF-8ness of the returned label, by setting *flags
to 0 or SVf_UTF8
.
const char * CopLABEL (COP *const cop)
const char * CopLABEL_len (COP *const cop, STRLEN *len)
const char * CopLABEL_len_flags(COP *const cop, STRLEN *len,
U32 *flags)
CopLINE
Returns the line number in the source code associated with the COP
c
line_t CopLINE(const COP * c)
CopSTASH
Returns the stash associated with c
.
HV * CopSTASH(const COP * c)
CopSTASH_eq
Returns a boolean as to whether or not hv
is the stash associated with c
.
bool CopSTASH_eq(const COP * c, const HV * hv)
CopSTASHPV
Returns the package name of the stash associated with c
, or NULL
if no associated stash
char * CopSTASHPV(const COP * c)
CopSTASHPV_set
Set the package name of the stash associated with c
, to the NUL-terminated C string p
, creating the package if necessary.
void CopSTASHPV_set(COP * c, const char * pv)
CopSTASH_set
Set the stash associated with c
to hv
.
bool CopSTASH_set(COP * c, HV * hv)
cop_store_label
NOTE: cop_store_label
is experimental and may change or be removed without notice.
Save a label into a cop_hints_hash
. You need to set flags to SVf_UTF8
for a UTF-8 label. Any other flag is ignored.
void cop_store_label(COP * const cop, const char *label,
STRLEN len, U32 flags)
PERL_SI
Use this typedef to declare variables that are to hold struct stackinfo
.
PL_curcop
The currently active COP (control op) roughly representing the current statement in the source.
On threaded perls, each thread has an independent copy of this variable; each initialized at creation time with the current value of the creating thread's copy.
COP* PL_curcop
RCPV_LEN
Returns the length of a pv created with rcpv_new()
. Note that this reflects the length of the string from the callers point of view, it does not include the mandatory null which is always injected at the end of the string by rcpv_new(). No checks are performed to ensure that pv
was actually allocated with rcpv_new()
, it is the callers responsibility to ensure that this is the case.
RCPV * RCPV_LEN(char *pv)
RCPV_REFCNT_dec
Decrements the refcount for a char *
pointer which was created with a call to rcpv_new()
. Same as calling rcpv_free(). No checks are performed to ensure that pv
was actually allocated with rcpv_new()
, it is the callers responsibility to ensure that this is the case.
RCPV * RCPV_REFCNT_dec(char *pv)
RCPV_REFCNT_inc
Increments the refcount for a char *
pointer which was created with a call to rcpv_new()
. Same as calling rcpv_copy(). No checks are performed to ensure that pv
was actually allocated with rcpv_new()
, it is the callers responsibility to ensure that this is the case.
RCPV * RCPV_REFCNT_inc(char *pv)
RCPV_REFCOUNT
Returns the refcount for a pv created with rcpv_new()
. No checks are performed to ensure that pv
was actually allocated with rcpv_new()
, it is the callers responsibility to ensure that this is the case.
RCPV * RCPV_REFCOUNT(char *pv)
RCPVx
Returns the RCPV structure (struct rcpv) for a refcounted string pv created with rcpv_new()
. No checks are performed to ensure that pv
was actually allocated with rcpv_new()
, it is the callers responsibility to ensure that this is the case.
RCPV * RCPVx(char *pv)
custom_op_register
Register a custom op. See "Custom Operators" in perlguts.
NOTE: custom_op_register
must be explicitly called as Perl_custom_op_register
with an aTHX_
parameter.
void Perl_custom_op_register(pTHX_ Perl_ppaddr_t ppaddr,
const XOP *xop)
Perl_custom_op_xop
Return the XOP structure for a given custom op. This macro should be considered internal to OP_NAME
and the other access macros: use them instead. This macro does call a function. Prior to 5.19.6, this was implemented as a function.
const XOP * Perl_custom_op_xop(pTHX_ const OP *o)
XopDISABLE
Temporarily disable a member of the XOP, by clearing the appropriate flag.
void XopDISABLE(XOP *xop, token which)
XopENABLE
Reenable a member of the XOP which has been disabled.
void XopENABLE(XOP *xop, token which)
XopENTRY
Return a member of the XOP structure. which
is a cpp token indicating which entry to return. If the member is not set this will return a default value. The return type depends on which
. This macro evaluates its arguments more than once. If you are using Perl_custom_op_xop
to retrieve a XOP *
from a OP *
, use the more efficient "XopENTRYCUSTOM" instead.
XopENTRY(XOP *xop, token which)
XopENTRYCUSTOM
Exactly like XopENTRY(XopENTRY(Perl_custom_op_xop(aTHX_ o), which)
but more efficient. The which
parameter is identical to "XopENTRY".
XopENTRYCUSTOM(const OP *o, token which)
XopENTRY_set
Set a member of the XOP structure. which
is a cpp token indicating which entry to set. See "Custom Operators" in perlguts for details about the available members and how they are used. This macro evaluates its argument more than once.
void XopENTRY_set(XOP *xop, token which, value)
XopFLAGS
Return the XOP's flags.
U32 XopFLAGS(XOP *xop)
This section documents functions to manipulate CVs which are code-values, meaning subroutines. For more information, see perlguts.
caller_cx
The XSUB-writer's equivalent of caller(). The returned PERL_CONTEXT
structure can be interrogated to find all the information returned to Perl by caller
. Note that XSUBs don't get a stack frame, so caller_cx(0, NULL)
will return information for the immediately-surrounding Perl code.
This function skips over the automatic calls to &DB::sub
made on the behalf of the debugger. If the stack frame requested was a sub called by DB::sub
, the return value will be the frame for the call to DB::sub
, since that has the correct line number/etc. for the call site. If dbcxp is non-NULL
, it will be set to a pointer to the frame for the sub call itself.
const PERL_CONTEXT * caller_cx(I32 level,
const PERL_CONTEXT **dbcxp)
CvDEPTH
Returns the recursion level of the CV sv
. Hence >= 2 indicates we are in a recursive call.
I32 * CvDEPTH(const CV * const sv)
CvGV
Returns the GV associated with the CV sv
, reifying it if necessary.
GV * CvGV(CV *sv)
CvSTASH
Returns the stash of the CV. A stash is the symbol table hash, containing the package-scoped variables in the package where the subroutine was defined. For more information, see perlguts.
This also has a special use with XS AUTOLOAD subs. See "Autoloading with XSUBs" in perlguts.
HV* CvSTASH(CV* cv)
find_runcv
Locate the CV corresponding to the currently executing sub or eval. If db_seqp
is non_null, skip CVs that are in the DB package and populate *db_seqp
with the cop sequence number at the point that the DB:: code was entered. (This allows debuggers to eval in the scope of the breakpoint rather than in the scope of the debugger itself.)
CV * find_runcv(U32 *db_seqp)
get_cv
get_cvn_flags
get_cvs
These return the CV of the specified Perl subroutine. flags
are passed to gv_fetchpvn_flags
. If GV_ADD
is set and the Perl subroutine does not exist then it will be declared (which has the same effect as saying sub name;
). If GV_ADD
is not set and the subroutine does not exist, then NULL is returned.
The forms differ only in how the subroutine is specified.. With get_cvs
, the name is a literal C string, enclosed in double quotes. With get_cv
, the name is given by the name
parameter, which must be a NUL-terminated C string. With get_cvn_flags
, the name is also given by the name
parameter, but it is a Perl string (possibly containing embedded NUL bytes), and its length in bytes is contained in the len
parameter.
NOTE: the perl_get_cv()
form is deprecated.
NOTE: the perl_get_cvn_flags()
form is deprecated.
NOTE: the perl_get_cvs()
form is deprecated.
CV * get_cv (const char *name, I32 flags)
CV * get_cvn_flags(const char *name, STRLEN len, I32 flags)
CV * get_cvs ("string", I32 flags)
Nullcv
DEPRECATED!
It is planned to remove Nullcv
from a future release of Perl. Do not use it for new code; remove it from existing code.
Null CV pointer.
(deprecated - use (CV *)NULL
instead)
av_dump
Dumps the contents of an AV to the STDERR
filehandle, Similar to using Devel::Peek on an arrayref but does not expect an RV wrapper. Dumps contents to a depth of 3 levels deep.
void av_dump(AV *av)
deb
deb_nocontext
When perl is compiled with -DDEBUGGING
, this prints to STDERR the information given by the arguments, prefaced by the name of the file containing the script causing the call, and the line number within that file.
If the v
(verbose) debugging option is in effect, the process id is also printed.
The two forms differ only in that deb_nocontext
does not take a thread context (aTHX
) parameter, so is used in situations where the caller doesn't already have the thread context.
NOTE: deb
must be explicitly called as Perl_deb
with an aTHX_
parameter.
void Perl_deb (pTHX_ const char *pat, ...)
void deb_nocontext(const char *pat, ...)
debstack
Dump the current stack
I32 debstack()
dump_all
Dumps the entire optree of the current program starting at PL_main_root
to STDERR
. Also dumps the optrees for all visible subroutines in PL_defstash
.
void dump_all()
dump_c_backtrace
Dumps the C backtrace to the given fp
.
Returns true if a backtrace could be retrieved, false if not.
bool dump_c_backtrace(PerlIO *fp, int max_depth, int skip)
dump_form
Dumps the contents of the format contained in the GV gv
to STDERR
, or a message that one doesn't exist.
void dump_form(const GV *gv)
dump_packsubs
Dumps the optrees for all visible subroutines in stash
.
void dump_packsubs(const HV *stash)
get_c_backtrace_dump
Returns a SV containing a dump of depth
frames of the call stack, skipping the skip
innermost ones. depth
of 20 is usually enough.
The appended output looks like:
...
1 10e004812:0082 Perl_croak util.c:1716 /usr/bin/perl
2 10df8d6d2:1d72 perl_parse perl.c:3975 /usr/bin/perl
...
The fields are tab-separated. The first column is the depth (zero being the innermost non-skipped frame). In the hex:offset, the hex is where the program counter was in S_parse_body
, and the :offset (might be missing) tells how much inside the S_parse_body
the program counter was.
The util.c:1716
is the source code file and line number.
The /usr/bin/perl is obvious (hopefully).
Unknowns are "-"
. Unknowns can happen unfortunately quite easily: if the platform doesn't support retrieving the information; if the binary is missing the debug information; if the optimizer has transformed the code by for example inlining.
SV * get_c_backtrace_dump(int max_depth, int skip)
gv_dump
Dump the name and, if they differ, the effective name of the GV gv
to STDERR
.
void gv_dump(GV *gv)
HAS_BACKTRACE
This symbol, if defined, indicates that the backtrace()
routine is available to get a stack trace. The execinfo.h header must be included to use this routine.
hv_dump
Dumps the contents of an HV to the STDERR
filehandle. Similar to using Devel::Peek on an hashref but does not expect an RV wrapper. Dumps contents to a depth of 3 levels deep.
void hv_dump(HV *hv)
magic_dump
Dumps the contents of the MAGIC mg
to STDERR
.
void magic_dump(const MAGIC *mg)
op_class
Given an op, determine what type of struct it has been allocated as. Returns one of the OPclass enums, such as OPclass_LISTOP.
OPclass op_class(const OP *o)
op_dump
Dumps the optree starting at OP o
to STDERR
.
void op_dump(const OP *o)
PL_op
Described in perlhacktips.
PL_sv_serial
Described in perlhacktips.
pmop_dump
Dump an OP that is related to Pattern Matching, such as s/foo/bar/
; these require special handling.
void pmop_dump(PMOP *pm)
sv_dump
Dumps the contents of an SV to the STDERR
filehandle.
For an example of its output, see Devel::Peek. If the item is an SvROK it will dump items to a depth of 4, otherwise it will dump only the top level item, which means that it will not dump the contents of an AV * or HV *. For that use av_dump()
or hv_dump()
.
void sv_dump(SV *sv)
sv_dump_depth
Dumps the contents of an SV to the STDERR
filehandle to the depth requested. This function can be used on any SV derived type (GV, HV, AV) with an appropriate cast. This is a more flexible variant of sv_dump(). For example
HV *hv = ...;
sv_dump_depth((SV*)hv, 2);
would dump the hv, its keys and values, but would not recurse into any RV values.
void sv_dump_depth(SV *sv, I32 depth)
vdeb
This is like "deb"
, but args
are an encapsulated argument list.
void vdeb(const char *pat, va_list *args)
form
form_nocontext
These take a sprintf-style format pattern and conventional (non-SV) arguments and return the formatted string.
(char *) Perl_form(aTHX_ const char* pat, ...)
They can be used any place a string (char *) is required:
char * s = form_nocontext("%d.%d", major, minor);
They each return a temporary that will be freed "soon", automatically by the system, at the same time that SVs operated on by "sv_2mortal"
are freed.
Use the result immediately, or copy to a stable place for longer retention. This is contrary to the incorrect previous documentation of these that claimed that the return was a single per-thread buffer. That was (and is) actually true only when these are called during global destruction.
The two forms differ only in that form_nocontext
does not take a thread context (aTHX
) parameter, so is used in situations where the caller doesn't already have the thread context.
"vform"
is the same except the arguments are an encapsulated argument list.
NOTE: form
must be explicitly called as Perl_form
with an aTHX_
parameter.
char * Perl_form (pTHX_ const char *pat, ...)
char * form_nocontext(const char *pat, ...)
mess
mess_nocontext
These take a sprintf-style format pattern and argument list, which are used to generate a string message. If the message does not end with a newline, then it will be extended with some indication of the current location in the code, as described for "mess_sv"
.
Normally, the resulting message is returned in a new mortal SV. But during global destruction a single SV may be shared between uses of this function.
The two forms differ only in that mess_nocontext
does not take a thread context (aTHX
) parameter, so is used in situations where the caller doesn't already have the thread context.
NOTE: mess
must be explicitly called as Perl_mess
with an aTHX_
parameter.
SV * Perl_mess (pTHX_ const char *pat, ...)
SV * mess_nocontext(const char *pat, ...)
mess_sv
Expands a message, intended for the user, to include an indication of the current location in the code, if the message does not already appear to be complete.
basemsg
is the initial message or object. If it is a reference, it will be used as-is and will be the result of this function. Otherwise it is used as a string, and if it already ends with a newline, it is taken to be complete, and the result of this function will be the same string. If the message does not end with a newline, then a segment such as at foo.pl line 37
will be appended, and possibly other clauses indicating the current state of execution. The resulting message will end with a dot and a newline.
Normally, the resulting message is returned in a new mortal SV. During global destruction a single SV may be shared between uses of this function. If consume
is true, then the function is permitted (but not required) to modify and return basemsg
instead of allocating a new SV.
SV * mess_sv(SV *basemsg, bool consume)
pv_display
Similar to
pv_escape(dsv,pv,cur,pvlim,PERL_PV_ESCAPE_QUOTE);
except that an additional "\0" will be appended to the string when len > cur and pv[cur] is "\0".
Note that the final string may be up to 7 chars longer than pvlim.
char * pv_display(SV *dsv, const char *pv, STRLEN cur,
STRLEN len, STRLEN pvlim)
pv_escape
Escapes at most the first count
chars of pv
and puts the results into dsv
such that the size of the escaped string will not exceed max
chars and will not contain any incomplete escape sequences. The number of bytes escaped will be returned in the STRLEN *escaped
parameter if it is not null. When the dsv
parameter is null no escaping actually occurs, but the number of bytes that would be escaped were it not null will be calculated.
If flags contains PERL_PV_ESCAPE_QUOTE
then any double quotes in the string will also be escaped.
Normally the SV will be cleared before the escaped string is prepared, but when PERL_PV_ESCAPE_NOCLEAR
is set this will not occur.
If PERL_PV_ESCAPE_UNI
is set then the input string is treated as UTF-8. If PERL_PV_ESCAPE_UNI_DETECT
is set then the input string is scanned using is_utf8_string()
to determine if it is UTF-8.
If PERL_PV_ESCAPE_ALL
is set then all input chars will be output using \x01F1
style escapes, otherwise if PERL_PV_ESCAPE_NONASCII
is set, only non-ASCII chars will be escaped using this style; otherwise, only chars above 255 will be so escaped; other non printable chars will use octal or common escaped patterns like \n
. Otherwise, if PERL_PV_ESCAPE_NOBACKSLASH
then all chars below 255 will be treated as printable and will be output as literals. The PERL_PV_ESCAPE_NON_WC
modifies the previous rules to cause word chars, unicode or otherwise, to be output as literals, note this uses the *unicode* rules for deciding on word characters.
If PERL_PV_ESCAPE_FIRSTCHAR
is set then only the first char of the string will be escaped, regardless of max. If the output is to be in hex, then it will be returned as a plain hex sequence. Thus the output will either be a single char, an octal escape sequence, a special escape like \n
or a hex value.
If PERL_PV_ESCAPE_RE
is set then the escape char used will be a "%"
and not a "\\"
. This is because regexes very often contain backslashed sequences, whereas "%"
is not a particularly common character in patterns.
Returns a pointer to the escaped text as held by dsv
.
char * pv_escape(SV *dsv, char const * const str,
const STRLEN count, STRLEN max,
STRLEN * const escaped, U32 flags)
pv_pretty
Converts a string into something presentable, handling escaping via pv_escape()
and supporting quoting and ellipses.
If the PERL_PV_PRETTY_QUOTE
flag is set then the result will be double quoted with any double quotes in the string escaped. Otherwise if the PERL_PV_PRETTY_LTGT
flag is set then the result be wrapped in angle brackets.
If the PERL_PV_PRETTY_ELLIPSES
flag is set and not all characters in string were output then an ellipsis ...
will be appended to the string. Note that this happens AFTER it has been quoted.
If start_color
is non-null then it will be inserted after the opening quote (if there is one) but before the escaped text. If end_color
is non-null then it will be inserted after the escaped text but before any quotes or ellipses.
Returns a pointer to the prettified text as held by dsv
.
char * pv_pretty(SV *dsv, char const * const str,
const STRLEN count, const STRLEN max,
char const * const start_color,
char const * const end_color, const U32 flags)
vform
Like "form"
except the arguments are an encapsulated argument list.
char * vform(const char *pat, va_list *args)
vmess
pat
and args
are a sprintf-style format pattern and encapsulated argument list, respectively. These are used to generate a string message. If the message does not end with a newline, then it will be extended with some indication of the current location in the code, as described for "mess_sv".
Normally, the resulting message is returned in a new mortal SV. During global destruction a single SV may be shared between uses of this function.
SV * vmess(const char *pat, va_list *args)
call_atexit
Add a function fn
to the list of functions to be called at global destruction. ptr
will be passed as an argument to fn
; it can point to a struct
so that you can pass anything you want.
Note that under threads, fn
may run multiple times. This is because the list is executed each time the current or any descendent thread terminates.
void call_atexit(ATEXIT_t fn, void *ptr)
cv_clone
Clone a CV, making a lexical closure. proto
supplies the prototype of the function: its code, pad structure, and other attributes. The prototype is combined with a capture of outer lexicals to which the code refers, which are taken from the currently-executing instance of the immediately surrounding code.
CV * cv_clone(CV *proto)
cv_name
Returns an SV containing the name of the CV, mainly for use in error reporting. The CV may actually be a GV instead, in which case the returned SV holds the GV's name. Anything other than a GV or CV is treated as a string already holding the sub name, but this could change in the future.
An SV may be passed as a second argument. If so, the name will be assigned to it and it will be returned. Otherwise the returned SV will be a new mortal.
If flags
has the CV_NAME_NOTQUAL
bit set, then the package name will not be included. If the first argument is neither a CV nor a GV, this flag is ignored (subject to change).
SV * cv_name(CV *cv, SV *sv, U32 flags)
cv_undef
Clear out all the active components of a CV. This can happen either by an explicit undef &foo
, or by the reference count going to zero. In the former case, we keep the CvOUTSIDE
pointer, so that any anonymous children can still follow the full lexical scope chain.
void cv_undef(CV *cv)
find_rundefsv
Returns the global variable $_
.
SV * find_rundefsv()
get_op_descs
DEPRECATED!
It is planned to remove get_op_descs
from a future release of Perl. Do not use it for new code; remove it from existing code.
Return a pointer to the array of all the descriptions of the various OPs Given an opcode from the enum in opcodes.h, PL_op_desc[opcode]
returns a pointer to a C language string giving its description.
char ** get_op_descs()
get_op_names
DEPRECATED!
It is planned to remove get_op_names
from a future release of Perl. Do not use it for new code; remove it from existing code.
Return a pointer to the array of all the names of the various OPs Given an opcode from the enum in opcodes.h, PL_op_name[opcode]
returns a pointer to a C language string giving its name.
char ** get_op_names()
intro_my
"Introduce" my
variables to visible status. This is called during parsing at the end of each statement to make lexical variables visible to subsequent statements.
U32 intro_my()
load_module
load_module_nocontext
These load the module whose name is pointed to by the string part of name
. Note that the actual module name, not its filename, should be given. Eg, "Foo::Bar" instead of "Foo/Bar.pm". ver, if specified and not NULL, provides version semantics similar to use Foo::Bar VERSION
. The optional trailing arguments can be used to specify arguments to the module's import()
method, similar to use Foo::Bar VERSION LIST
; their precise handling depends on the flags. The flags argument is a bitwise-ORed collection of any of PERL_LOADMOD_DENY
, PERL_LOADMOD_NOIMPORT
, or PERL_LOADMOD_IMPORT_OPS
(or 0 for no flags).
If PERL_LOADMOD_NOIMPORT
is set, the module is loaded as if with an empty import list, as in use Foo::Bar ()
; this is the only circumstance in which the trailing optional arguments may be omitted entirely. Otherwise, if PERL_LOADMOD_IMPORT_OPS
is set, the trailing arguments must consist of exactly one OP*
, containing the op tree that produces the relevant import arguments. Otherwise, the trailing arguments must all be SV*
values that will be used as import arguments; and the list must be terminated with (SV*) NULL
. If neither PERL_LOADMOD_NOIMPORT
nor PERL_LOADMOD_IMPORT_OPS
is set, the trailing NULL
pointer is needed even if no import arguments are desired. The reference count for each specified SV*
argument is decremented. In addition, the name
argument is modified.
If PERL_LOADMOD_DENY
is set, the module is loaded as if with no
rather than use
.
load_module
and load_module_nocontext
have the same apparent signature, but the former hides the fact that it is accessing a thread context parameter. So use the latter when you get a compilation error about pTHX
.
void load_module (U32 flags, SV *name, SV *ver, ...)
void load_module_nocontext(U32 flags, SV *name, SV *ver, ...)
my_exit
A wrapper for the C library exit(3), honoring what "PL_exit_flags" in perlapi say to do.
void my_exit(U32 status)
my_failure_exit
Exit the running Perl process with an error.
On non-VMS platforms, this is essentially equivalent to "my_exit
", using errno
, but forces an en error code of 255 if errno
is 0.
On VMS, it takes care to set the appropriate severity bits in the exit status.
void my_failure_exit()
my_strlcat
The C library strlcat
if available, or a Perl implementation of it. This operates on C NUL
-terminated strings.
my_strlcat()
appends string src
to the end of dst
. It will append at most size - strlen(dst) - 1
bytes. It will then NUL
-terminate, unless size
is 0 or the original dst
string was longer than size
(in practice this should not happen as it means that either size
is incorrect or that dst
is not a proper NUL
-terminated string).
Note that size
is the full size of the destination buffer and the result is guaranteed to be NUL
-terminated if there is room. Note that room for the NUL
should be included in size
.
The return value is the total length that dst
would have if size
is sufficiently large. Thus it is the initial length of dst
plus the length of src
. If size
is smaller than the return, the excess was not appended.
Size_t my_strlcat(char *dst, const char *src, Size_t size)
my_strlcpy
The C library strlcpy
if available, or a Perl implementation of it. This operates on C NUL
-terminated strings.
my_strlcpy()
copies up to size - 1
bytes from the string src
to dst
, NUL
-terminating the result if size
is not 0.
The return value is the total length src
would be if the copy completely succeeded. If it is larger than size
, the excess was not copied.
Size_t my_strlcpy(char *dst, const char *src, Size_t size)
newPADNAMELIST
NOTE: newPADNAMELIST
is experimental and may change or be removed without notice.
Creates a new pad name list. max
is the highest index for which space is allocated.
PADNAMELIST * newPADNAMELIST(size_t max)
newPADNAMEouter
NOTE: newPADNAMEouter
is experimental and may change or be removed without notice.
Constructs and returns a new pad name. Only use this function for names that refer to outer lexicals. (See also "newPADNAMEpvn".) outer
is the outer pad name that this one mirrors. The returned pad name has the PADNAMEf_OUTER
flag already set.
PADNAME * newPADNAMEouter(PADNAME *outer)
newPADNAMEpvn
NOTE: newPADNAMEpvn
is experimental and may change or be removed without notice.
Constructs and returns a new pad name. s
must be a UTF-8 string. Do not use this for pad names that point to outer lexicals. See "newPADNAMEouter"
.
PADNAME * newPADNAMEpvn(const char *s, STRLEN len)
nothreadhook
Stub that provides thread hook for perl_destruct when there are no threads.
int nothreadhook()
pad_add_anon
Allocates a place in the currently-compiling pad (via "pad_alloc") for an anonymous function that is lexically scoped inside the currently-compiling function. The function func
is linked into the pad, and its CvOUTSIDE
link to the outer scope is weakened to avoid a reference loop.
One reference count is stolen, so you may need to do SvREFCNT_inc(func)
.
optype
should be an opcode indicating the type of operation that the pad entry is to support. This doesn't affect operational semantics, but is used for debugging.
PADOFFSET pad_add_anon(CV *func, I32 optype)
pad_add_name_pv
Exactly like "pad_add_name_pvn", but takes a nul-terminated string instead of a string/length pair.
PADOFFSET pad_add_name_pv(const char *name, const U32 flags,
HV *typestash, HV *ourstash)
pad_add_name_pvn
Allocates a place in the currently-compiling pad for a named lexical variable. Stores the name and other metadata in the name part of the pad, and makes preparations to manage the variable's lexical scoping. Returns the offset of the allocated pad slot.
namepv
/namelen
specify the variable's name in UTF-8, including leading sigil. If typestash
is non-null, the name is for a typed lexical, and this identifies the type. If ourstash
is non-null, it's a lexical reference to a package variable, and this identifies the package. The following flags can be OR'ed together:
padadd_OUR redundantly specifies if it's a package var
padadd_STATE variable will retain value persistently
padadd_NO_DUP_CHECK skip check for lexical shadowing
padadd_FIELD specifies that the lexical is a field for a class
PADOFFSET pad_add_name_pvn(const char *namepv, STRLEN namelen,
U32 flags, HV *typestash,
HV *ourstash)
pad_add_name_sv
Exactly like "pad_add_name_pvn", but takes the name string in the form of an SV instead of a string/length pair.
PADOFFSET pad_add_name_sv(SV *name, U32 flags, HV *typestash,
HV *ourstash)
pad_alloc
NOTE: pad_alloc
is experimental and may change or be removed without notice.
Allocates a place in the currently-compiling pad, returning the offset of the allocated pad slot. No name is initially attached to the pad slot. tmptype
is a set of flags indicating the kind of pad entry required, which will be set in the value SV for the allocated pad entry:
SVs_PADMY named lexical variable ("my", "our", "state")
SVs_PADTMP unnamed temporary store
SVf_READONLY constant shared between recursion levels
SVf_READONLY
has been supported here only since perl 5.20. To work with earlier versions as well, use SVf_READONLY|SVs_PADTMP
. SVf_READONLY
does not cause the SV in the pad slot to be marked read-only, but simply tells pad_alloc
that it will be made read-only (by the caller), or at least should be treated as such.
optype
should be an opcode indicating the type of operation that the pad entry is to support. This doesn't affect operational semantics, but is used for debugging.
PADOFFSET pad_alloc(I32 optype, U32 tmptype)
pad_findmy_pv
Exactly like "pad_findmy_pvn", but takes a nul-terminated string instead of a string/length pair.
PADOFFSET pad_findmy_pv(const char *name, U32 flags)
pad_findmy_pvn
Given the name of a lexical variable, find its position in the currently-compiling pad. namepv
/namelen
specify the variable's name, including leading sigil. flags
is reserved and must be zero. If it is not in the current pad but appears in the pad of any lexically enclosing scope, then a pseudo-entry for it is added in the current pad. Returns the offset in the current pad, or NOT_IN_PAD
if no such lexical is in scope.
PADOFFSET pad_findmy_pvn(const char *namepv, STRLEN namelen,
U32 flags)
pad_findmy_sv
Exactly like "pad_findmy_pvn", but takes the name string in the form of an SV instead of a string/length pair.
PADOFFSET pad_findmy_sv(SV *name, U32 flags)
padnamelist_fetch
NOTE: padnamelist_fetch
is experimental and may change or be removed without notice.
Fetches the pad name from the given index.
PADNAME * padnamelist_fetch(PADNAMELIST *pnl, SSize_t key)
padnamelist_store
NOTE: padnamelist_store
is experimental and may change or be removed without notice.
Stores the pad name (which may be null) at the given index, freeing any existing pad name in that slot.
PADNAME ** padnamelist_store(PADNAMELIST *pnl, SSize_t key,
PADNAME *val)
pad_tidy
NOTE: pad_tidy
is experimental and may change or be removed without notice.
Tidy up a pad at the end of compilation of the code to which it belongs. Jobs performed here are: remove most stuff from the pads of anonsub prototypes; give it a @_
; mark temporaries as such. type
indicates the kind of subroutine:
padtidy_SUB ordinary subroutine
padtidy_SUBCLONE prototype for lexical closure
padtidy_FORMAT format
void pad_tidy(padtidy_type type)
PERL_ASYNC_CHECK
Described in perlinterp.
void PERL_ASYNC_CHECK()
perl_clone
Create and return a new interpreter by cloning the current one.
perl_clone
takes these flags as parameters:
CLONEf_COPY_STACKS
- is used to, well, copy the stacks also, without it we only clone the data and zero the stacks, with it we copy the stacks and the new perl interpreter is ready to run at the exact same point as the previous one. The pseudo-fork code uses COPY_STACKS
while the threads->create doesn't.
CLONEf_KEEP_PTR_TABLE
- perl_clone
keeps a ptr_table with the pointer of the old variable as a key and the new variable as a value, this allows it to check if something has been cloned and not clone it again, but rather just use the value and increase the refcount. If KEEP_PTR_TABLE
is not set then perl_clone
will kill the ptr_table using the function ptr_table_free(PL_ptr_table); PL_ptr_table = NULL;
. A reason to keep it around is if you want to dup some of your own variables which are outside the graph that perl scans.
CLONEf_CLONE_HOST
- This is a win32 thing, it is ignored on unix, it tells perl's win32host code (which is c++) to clone itself, this is needed on win32 if you want to run two threads at the same time, if you just want to do some stuff in a separate perl interpreter and then throw it away and return to the original one, you don't need to do anything.
PerlInterpreter * perl_clone(PerlInterpreter *proto_perl,
UV flags)
perl_construct
Initializes a new Perl interpreter. See perlembed.
void perl_construct(PerlInterpreter *my_perl)
perl_destruct
Shuts down a Perl interpreter. See perlembed for a tutorial.
my_perl
points to the Perl interpreter. It must have been previously created through the use of "perl_alloc" and "perl_construct". It may have been initialised through "perl_parse", and may have been used through "perl_run" and other means. This function should be called for any Perl interpreter that has been constructed with "perl_construct", even if subsequent operations on it failed, for example if "perl_parse" returned a non-zero value.
If the interpreter's PL_exit_flags
word has the PERL_EXIT_DESTRUCT_END
flag set, then this function will execute code in END
blocks before performing the rest of destruction. If it is desired to make any use of the interpreter between "perl_parse" and "perl_destruct" other than just calling "perl_run", then this flag should be set early on. This matters if "perl_run" will not be called, or if anything else will be done in addition to calling "perl_run".
Returns a value be a suitable value to pass to the C library function exit
(or to return from main
), to serve as an exit code indicating the nature of the way the interpreter terminated. This takes into account any failure of "perl_parse" and any early exit from "perl_run". The exit code is of the type required by the host operating system, so because of differing exit code conventions it is not portable to interpret specific numeric values as having specific meanings.
int perl_destruct(PerlInterpreter *my_perl)
perl_parse
Tells a Perl interpreter to parse a Perl script. This performs most of the initialisation of a Perl interpreter. See perlembed for a tutorial.
my_perl
points to the Perl interpreter that is to parse the script. It must have been previously created through the use of "perl_alloc" and "perl_construct". xsinit
points to a callback function that will be called to set up the ability for this Perl interpreter to load XS extensions, or may be null to perform no such setup.
argc
and argv
supply a set of command-line arguments to the Perl interpreter, as would normally be passed to the main
function of a C program. argv[argc]
must be null. These arguments are where the script to parse is specified, either by naming a script file or by providing a script in a -e
option. If $0
will be written to in the Perl interpreter, then the argument strings must be in writable memory, and so mustn't just be string constants.
env
specifies a set of environment variables that will be used by this Perl interpreter. If non-null, it must point to a null-terminated array of environment strings. If null, the Perl interpreter will use the environment supplied by the environ
global variable.
This function initialises the interpreter, and parses and compiles the script specified by the command-line arguments. This includes executing code in BEGIN
, UNITCHECK
, and CHECK
blocks. It does not execute INIT
blocks or the main program.
Returns an integer of slightly tricky interpretation. The correct use of the return value is as a truth value indicating whether there was a failure in initialisation. If zero is returned, this indicates that initialisation was successful, and it is safe to proceed to call "perl_run" and make other use of it. If a non-zero value is returned, this indicates some problem that means the interpreter wants to terminate. The interpreter should not be just abandoned upon such failure; the caller should proceed to shut the interpreter down cleanly with "perl_destruct" and free it with "perl_free".
For historical reasons, the non-zero return value also attempts to be a suitable value to pass to the C library function exit
(or to return from main
), to serve as an exit code indicating the nature of the way initialisation terminated. However, this isn't portable, due to differing exit code conventions. An attempt is made to return an exit code of the type required by the host operating system, but because it is constrained to be non-zero, it is not necessarily possible to indicate every type of exit. It is only reliable on Unix, where a zero exit code can be augmented with a set bit that will be ignored. In any case, this function is not the correct place to acquire an exit code: one should get that from "perl_destruct".
int perl_parse(PerlInterpreter *my_perl, XSINIT_t xsinit,
int argc, char **argv, char **env)
perl_run
Tells a Perl interpreter to run its main program. See perlembed for a tutorial.
my_perl
points to the Perl interpreter. It must have been previously created through the use of "perl_alloc" and "perl_construct", and initialised through "perl_parse". This function should not be called if "perl_parse" returned a non-zero value, indicating a failure in initialisation or compilation.
This function executes code in INIT
blocks, and then executes the main program. The code to be executed is that established by the prior call to "perl_parse". If the interpreter's PL_exit_flags
word does not have the PERL_EXIT_DESTRUCT_END
flag set, then this function will also execute code in END
blocks. If it is desired to make any further use of the interpreter after calling this function, then END
blocks should be postponed to "perl_destruct" time by setting that flag.
Returns an integer of slightly tricky interpretation. The correct use of the return value is as a truth value indicating whether the program terminated non-locally. If zero is returned, this indicates that the program ran to completion, and it is safe to make other use of the interpreter (provided that the PERL_EXIT_DESTRUCT_END
flag was set as described above). If a non-zero value is returned, this indicates that the interpreter wants to terminate early. The interpreter should not be just abandoned because of this desire to terminate; the caller should proceed to shut the interpreter down cleanly with "perl_destruct" and free it with "perl_free".
For historical reasons, the non-zero return value also attempts to be a suitable value to pass to the C library function exit
(or to return from main
), to serve as an exit code indicating the nature of the way the program terminated. However, this isn't portable, due to differing exit code conventions. An attempt is made to return an exit code of the type required by the host operating system, but because it is constrained to be non-zero, it is not necessarily possible to indicate every type of exit. It is only reliable on Unix, where a zero exit code can be augmented with a set bit that will be ignored. In any case, this function is not the correct place to acquire an exit code: one should get that from "perl_destruct".
int perl_run(PerlInterpreter *my_perl)
PERL_SYS_INIT
PERL_SYS_INIT3
These provide system-specific tune up of the C runtime environment necessary to run Perl interpreters. Only one should be used, and it should be called only once, before creating any Perl interpreters.
They differ in that PERL_SYS_INIT3
also initializes env
.
void PERL_SYS_INIT (int *argc, char*** argv)
void PERL_SYS_INIT3(int *argc, char*** argv, char*** env)
PERL_SYS_TERM
Provides system-specific clean up of the C runtime environment after running Perl interpreters. This should be called only once, after freeing any remaining Perl interpreters.
void PERL_SYS_TERM()
PL_exit_flags
Contains flags controlling perl's behaviour on exit():
PERL_EXIT_DESTRUCT_END
If set, END blocks are executed when the interpreter is destroyed. This is normally set by perl itself after the interpreter is constructed.
PERL_EXIT_ABORT
Call abort()
on exit. This is used internally by perl itself to abort if exit is called while processing exit.
PERL_EXIT_WARN
Warn on exit.
PERL_EXIT_EXPECTED
Set by the "exit" in perlfunc operator.
U8 PL_exit_flags
PL_perl_destruct_level
This value may be set when embedding for full cleanup.
Possible values:
0 - none
1 - full
2 or greater - full with checks.
If $ENV{PERL_DESTRUCT_LEVEL}
is set to an integer greater than the value of PL_perl_destruct_level
its value is used instead.
On threaded perls, each thread has an independent copy of this variable; each initialized at creation time with the current value of the creating thread's copy.
signed char PL_perl_destruct_level
ptr_table_fetch
Look for sv
in the pointer-mapping table tbl
, returning its value, or NULL if not found.
void * ptr_table_fetch(PTR_TBL_t * const tbl,
const void * const sv)
ptr_table_free
Clear and free a ptr table
void ptr_table_free(PTR_TBL_t * const tbl)
ptr_table_new
Create a new pointer-mapping table
PTR_TBL_t * ptr_table_new()
ptr_table_split
Double the hash bucket size of an existing ptr table
void ptr_table_split(PTR_TBL_t * const tbl)
ptr_table_store
Add a new entry to a pointer-mapping table tbl
. In hash terms, oldsv
is the key; Cnewsv> is the value.
The names "old" and "new" are specific to the core's typical use of ptr_tables in thread cloning.
void ptr_table_store(PTR_TBL_t * const tbl,
const void * const oldsv,
void * const newsv)
require_pv
Tells Perl to require
the file named by the string argument. It is analogous to the Perl code eval "require '$file'"
. It's even implemented that way; consider using load_module instead.
NOTE: the perl_require_pv()
form is deprecated.
void require_pv(const char *pv)
vload_module
Like "load_module"
but the arguments are an encapsulated argument list.
void vload_module(U32 flags, SV *name, SV *ver, va_list *args)
sv_string_from_errnum
Generates the message string describing an OS error and returns it as an SV. errnum
must be a value that errno
could take, identifying the type of error.
If tgtsv
is non-null then the string will be written into that SV (overwriting existing content) and it will be returned. If tgtsv
is a null pointer then the string will be written into a new mortal SV which will be returned.
The message will be taken from whatever locale would be used by $!
, and will be encoded in the SV in whatever manner would be used by $!
. The details of this process are subject to future change. Currently, the message is taken from the C locale by default (usually producing an English message), and from the currently selected locale when in the scope of the use locale
pragma. A heuristic attempt is made to decode the message from the locale's character encoding, but it will only be decoded as either UTF-8 or ISO-8859-1. It is always correctly decoded in a UTF-8 locale, usually in an ISO-8859-1 locale, and never in any other locale.
The SV is always returned containing an actual string, and with no other OK bits set. Unlike $!
, a message is even yielded for errnum
zero (meaning success), and if no useful message is available then a useless string (currently empty) is returned.
SV * sv_string_from_errnum(int errnum, SV *tgtsv)
dXCPT
Set up necessary local variables for exception handling. See "Exception Handling" in perlguts.
dXCPT;
JMPENV_JUMP
Described in perlinterp.
void JMPENV_JUMP(int v)
JMPENV_PUSH
Described in perlinterp.
void JMPENV_PUSH(int v)
PL_restartop
Described in perlinterp.
XCPT_CATCH
Introduces a catch block. See "Exception Handling" in perlguts.
XCPT_RETHROW
Rethrows a previously caught exception. See "Exception Handling" in perlguts.
XCPT_RETHROW;
XCPT_TRY_END
Ends a try block. See "Exception Handling" in perlguts.
XCPT_TRY_START
Starts a try block. See "Exception Handling" in perlguts.
Also see "List of capability HAS_foo symbols".
DIRNAMLEN
This symbol, if defined, indicates to the C program that the length of directory entry names is provided by a d_namlen
field. Otherwise you need to do strlen()
on the d_name
field.
DOSUID
This symbol, if defined, indicates that the C program should check the script that it is executing for setuid/setgid bits, and attempt to emulate setuid/setgid on systems that have disabled setuid #! scripts because the kernel can't do it securely. It is up to the package designer to make sure that this emulation is done securely. Among other things, it should do an fstat on the script it just opened to make sure it really is a setuid/setgid script, it should make sure the arguments passed correspond exactly to the argument on the #! line, and it should not trust any subprocesses to which it must pass the filename rather than the file descriptor of the script to be executed.
EOF_NONBLOCK
This symbol, if defined, indicates to the C program that a read()
on a non-blocking file descriptor will return 0 on EOF
, and not the value held in RD_NODATA
(-1 usually, in that case!).
FCNTL_CAN_LOCK
This symbol, if defined, indicates that fcntl()
can be used for file locking. Normally on Unix systems this is defined. It may be undefined on VMS
.
FFLUSH_ALL
This symbol, if defined, tells that to flush all pending stdio output one must loop through all the stdio file handles stored in an array and fflush them. Note that if fflushNULL
is defined, fflushall will not even be probed for and will be left undefined.
FFLUSH_NULL
This symbol, if defined, tells that fflush(NULL)
correctly flushes all pending stdio output without side effects. In particular, on some platforms calling fflush(NULL)
*still* corrupts STDIN
if it is a pipe.
FILE_base
This macro is used to access the _base
field (or equivalent) of the FILE
structure pointed to by its argument. This macro will always be defined if USE_STDIO_BASE
is defined.
void * FILE_base(FILE * f)
FILE_bufsiz
This macro is used to determine the number of bytes in the I/O buffer pointed to by _base
field (or equivalent) of the FILE
structure pointed to its argument. This macro will always be defined if USE_STDIO_BASE
is defined.
Size_t FILE_bufsiz(FILE *f)
FILE_cnt
This macro is used to access the _cnt
field (or equivalent) of the FILE
structure pointed to by its argument. This macro will always be defined if USE_STDIO_PTR
is defined.
Size_t FILE_cnt(FILE * f)
FILE_ptr
This macro is used to access the _ptr
field (or equivalent) of the FILE
structure pointed to by its argument. This macro will always be defined if USE_STDIO_PTR
is defined.
void * FILE_ptr(FILE * f)
FLEXFILENAMES
This symbol, if defined, indicates that the system supports filenames longer than 14 characters.
HAS_DIR_DD_FD
This symbol, if defined, indicates that the DIR
* dirstream structure contains a member variable named dd_fd
.
HAS_DUP2
This symbol, if defined, indicates that the dup2
routine is available to duplicate file descriptors.
HAS_DUP3
This symbol, if defined, indicates that the dup3
routine is available to duplicate file descriptors.
HAS_FAST_STDIO
This symbol, if defined, indicates that the "fast stdio" is available to manipulate the stdio buffers directly.
HAS_FCHDIR
This symbol, if defined, indicates that the fchdir
routine is available to change directory using a file descriptor.
HAS_FCNTL
This symbol, if defined, indicates to the C program that the fcntl()
function exists.
HAS_FDCLOSE
This symbol, if defined, indicates that the fdclose
routine is available to free a FILE
structure without closing the underlying file descriptor. This function appeared in FreeBSD
10.2.
HAS_FPATHCONF
This symbol, if defined, indicates that pathconf()
is available to determine file-system related limits and options associated with a given open file descriptor.
HAS_FPOS64_T
This symbol will be defined if the C compiler supports fpos64_t
.
HAS_FSTATFS
This symbol, if defined, indicates that the fstatfs
routine is available to stat filesystems by file descriptors.
HAS_FSTATVFS
This symbol, if defined, indicates that the fstatvfs
routine is available to stat filesystems by file descriptors.
HAS_GETFSSTAT
This symbol, if defined, indicates that the getfsstat
routine is available to stat filesystems in bulk.
HAS_GETMNT
This symbol, if defined, indicates that the getmnt
routine is available to get filesystem mount info by filename.
HAS_GETMNTENT
This symbol, if defined, indicates that the getmntent
routine is available to iterate through mounted file systems to get their info.
HAS_HASMNTOPT
This symbol, if defined, indicates that the hasmntopt
routine is available to query the mount options of file systems.
HAS_LSEEK_PROTO
This symbol, if defined, indicates that the system provides a prototype for the lseek()
function. Otherwise, it is up to the program to supply one. A good guess is
extern off_t lseek(int, off_t, int);
HAS_MKDIR
This symbol, if defined, indicates that the mkdir
routine is available to create directories. Otherwise you should fork off a new process to exec /bin/mkdir.
HAS_OFF64_T
This symbol will be defined if the C compiler supports off64_t
.
HAS_OPENAT
This symbol is defined if the openat()
routine is available.
HAS_OPEN3
This manifest constant lets the C program know that the three argument form of open(2)
is available.
HAS_POLL
This symbol, if defined, indicates that the poll
routine is available to poll
active file descriptors. Please check I_POLL
and I_SYS_POLL
to know which header should be included as well.
HAS_READDIR
This symbol, if defined, indicates that the readdir
routine is available to read directory entries. You may have to include dirent.h. See "I_DIRENT"
.
HAS_READDIR64_R
This symbol, if defined, indicates that the readdir64_r
routine is available to readdir64 re-entrantly.
HAS_REWINDDIR
This symbol, if defined, indicates that the rewinddir
routine is available. You may have to include dirent.h. See "I_DIRENT"
.
HAS_RMDIR
This symbol, if defined, indicates that the rmdir
routine is available to remove directories. Otherwise you should fork off a new process to exec /bin/rmdir.
HAS_SEEKDIR
This symbol, if defined, indicates that the seekdir
routine is available. You may have to include dirent.h. See "I_DIRENT"
.
HAS_SELECT
This symbol, if defined, indicates that the select
routine is available to select
active file descriptors. If the timeout field is used, sys/time.h may need to be included.
HAS_SETVBUF
This symbol, if defined, indicates that the setvbuf
routine is available to change buffering on an open stdio stream. to a line-buffered mode.
HAS_STDIO_STREAM_ARRAY
This symbol, if defined, tells that there is an array holding the stdio streams.
HAS_STRUCT_FS_DATA
This symbol, if defined, indicates that the struct fs_data
to do statfs()
is supported.
HAS_STRUCT_STATFS
This symbol, if defined, indicates that the struct statfs
to do statfs()
is supported.
HAS_STRUCT_STATFS_F_FLAGS
This symbol, if defined, indicates that the struct statfs
does have the f_flags
member containing the mount flags of the filesystem containing the file. This kind of struct statfs
is coming from sys/mount.h (BSD
4.3), not from sys/statfs.h (SYSV
). Older BSDs
(like Ultrix) do not have statfs()
and struct statfs
, they have ustat()
and getmnt()
with struct ustat
and struct fs_data
.
HAS_TELLDIR
This symbol, if defined, indicates that the telldir
routine is available. You may have to include dirent.h. See "I_DIRENT"
.
HAS_USTAT
This symbol, if defined, indicates that the ustat
system call is available to query file system statistics by dev_t
.
I_FCNTL
This manifest constant tells the C program to include fcntl.h.
#ifdef I_FCNTL
#include <fcntl.h>
#endif
I_SYS_DIR
This symbol, if defined, indicates to the C program that it should include sys/dir.h.
#ifdef I_SYS_DIR
#include <sys_dir.h>
#endif
I_SYS_FILE
This symbol, if defined, indicates to the C program that it should include sys/file.h to get definition of R_OK
and friends.
#ifdef I_SYS_FILE
#include <sys_file.h>
#endif
I_SYS_NDIR
This symbol, if defined, indicates to the C program that it should include sys/ndir.h.
#ifdef I_SYS_NDIR
#include <sys_ndir.h>
#endif
I_SYS_STATFS
This symbol, if defined, indicates that sys/statfs.h exists.
#ifdef I_SYS_STATFS
#include <sys_statfs.h>
#endif
LSEEKSIZE
This symbol holds the number of bytes used by the Off_t
.
RD_NODATA
This symbol holds the return code from read()
when no data is present on the non-blocking file descriptor. Be careful! If EOF_NONBLOCK
is not defined, then you can't distinguish between no data and EOF
by issuing a read()
. You'll have to find another way to tell for sure!
READDIR64_R_PROTO
This symbol encodes the prototype of readdir64_r
. It is zero if d_readdir64_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_readdir64_r
is defined.
STDCHAR
This symbol is defined to be the type of char used in stdio.h. It has the values "unsigned char" or "char".
STDIO_CNT_LVALUE
This symbol is defined if the FILE_cnt
macro can be used as an lvalue.
STDIO_PTR_LVAL_NOCHANGE_CNT
This symbol is defined if using the FILE_ptr
macro as an lvalue to increase the pointer by n leaves File_cnt(fp)
unchanged.
STDIO_PTR_LVAL_SETS_CNT
This symbol is defined if using the FILE_ptr
macro as an lvalue to increase the pointer by n has the side effect of decreasing the value of File_cnt(fp)
by n.
STDIO_PTR_LVALUE
This symbol is defined if the FILE_ptr
macro can be used as an lvalue.
STDIO_STREAM_ARRAY
This symbol tells the name of the array holding the stdio streams. Usual values include _iob
, __iob
, and __sF
.
ST_INO_SIGN
This symbol holds the signedness of struct stat
's st_ino
. 1 for unsigned, -1 for signed.
ST_INO_SIZE
This variable contains the size of struct stat
's st_ino
in bytes.
VAL_EAGAIN
This symbol holds the errno error code set by read()
when no data was present on the non-blocking file descriptor.
VAL_O_NONBLOCK
This symbol is to be used during open()
or fcntl(F_SETFL)
to turn on non-blocking I/O for the file descriptor. Note that there is no way back, i.e. you cannot turn it blocking again this way. If you wish to alternatively switch between blocking and non-blocking, use the ioctl(FIOSNBIO)
call instead, but that is not supported by all devices.
VOID_CLOSEDIR
This symbol, if defined, indicates that the closedir()
routine does not return a value.
Also "List of capability HAS_foo symbols" lists capabilities that arent in this section. For example HAS_ASINH
, for the hyperbolic sine function.
CASTFLAGS
This symbol contains flags that say what difficulties the compiler has casting odd floating values to unsigned long:
0 = ok
1 = couldn't cast < 0
2 = couldn't cast >= 0x80000000
4 = couldn't cast in argument expression list
CASTNEGFLOAT
This symbol is defined if the C compiler can cast negative numbers to unsigned longs, ints and shorts.
DOUBLE_HAS_INF
This symbol, if defined, indicates that the double has the infinity.
DOUBLE_HAS_NAN
This symbol, if defined, indicates that the double has the not-a-number.
DOUBLE_HAS_NEGATIVE_ZERO
This symbol, if defined, indicates that the double has the negative_zero
.
DOUBLE_HAS_SUBNORMALS
This symbol, if defined, indicates that the double has the subnormals (denormals).
DOUBLEINFBYTES
This symbol, if defined, is a comma-separated list of hexadecimal bytes for the double precision infinity.
DOUBLEKIND
DOUBLEKIND
will be one of DOUBLE_IS_IEEE_754_32_BIT_LITTLE_ENDIAN
DOUBLE_IS_IEEE_754_32_BIT_BIG_ENDIAN
DOUBLE_IS_IEEE_754_64_BIT_LITTLE_ENDIAN
DOUBLE_IS_IEEE_754_64_BIT_BIG_ENDIAN
DOUBLE_IS_IEEE_754_128_BIT_LITTLE_ENDIAN
DOUBLE_IS_IEEE_754_128_BIT_BIG_ENDIAN
DOUBLE_IS_IEEE_754_64_BIT_MIXED_ENDIAN_LE_BE
DOUBLE_IS_IEEE_754_64_BIT_MIXED_ENDIAN_BE_LE
DOUBLE_IS_VAX_F_FLOAT
DOUBLE_IS_VAX_D_FLOAT
DOUBLE_IS_VAX_G_FLOAT
DOUBLE_IS_IBM_SINGLE_32_BIT
DOUBLE_IS_IBM_DOUBLE_64_BIT
DOUBLE_IS_CRAY_SINGLE_64_BIT
DOUBLE_IS_UNKNOWN_FORMAT
DOUBLEMANTBITS
This symbol, if defined, tells how many mantissa bits there are in double precision floating point format. Note that this is usually DBL_MANT_DIG
minus one, since with the standard IEEE
754 formats DBL_MANT_DIG
includes the implicit bit, which doesn't really exist.
DOUBLENANBYTES
This symbol, if defined, is a comma-separated list of hexadecimal bytes (0xHH) for the double precision not-a-number.
DOUBLESIZE
This symbol contains the size of a double, so that the C preprocessor can make decisions based on it.
DOUBLE_STYLE_CRAY
This symbol, if defined, indicates that the double is the 64-bit CRAY
mainframe format.
DOUBLE_STYLE_IBM
This symbol, if defined, indicates that the double is the 64-bit IBM
mainframe format.
DOUBLE_STYLE_IEEE
This symbol, if defined, indicates that the double is the 64-bit IEEE
754.
DOUBLE_STYLE_VAX
This symbol, if defined, indicates that the double is the 64-bit VAX
format D or G.
HAS_ATOLF
This symbol, if defined, indicates that the atolf
routine is available to convert strings into long doubles.
HAS_CLASS
This symbol, if defined, indicates that the class
routine is available to classify doubles. Available for example in AIX
. The returned values are defined in float.h and are:
FP_PLUS_NORM Positive normalized, nonzero
FP_MINUS_NORM Negative normalized, nonzero
FP_PLUS_DENORM Positive denormalized, nonzero
FP_MINUS_DENORM Negative denormalized, nonzero
FP_PLUS_ZERO +0.0
FP_MINUS_ZERO -0.0
FP_PLUS_INF +INF
FP_MINUS_INF -INF
FP_NANS Signaling Not a Number (NaNS)
FP_NANQ Quiet Not a Number (NaNQ)
HAS_FINITE
This symbol, if defined, indicates that the finite
routine is available to check whether a double is finite
(non-infinity non-NaN).
HAS_FINITEL
This symbol, if defined, indicates that the finitel
routine is available to check whether a long double is finite (non-infinity non-NaN).
HAS_FPCLASS
This symbol, if defined, indicates that the fpclass
routine is available to classify doubles. Available for example in Solaris/SVR4
. The returned values are defined in ieeefp.h and are:
FP_SNAN signaling NaN
FP_QNAN quiet NaN
FP_NINF negative infinity
FP_PINF positive infinity
FP_NDENORM negative denormalized non-zero
FP_PDENORM positive denormalized non-zero
FP_NZERO negative zero
FP_PZERO positive zero
FP_NNORM negative normalized non-zero
FP_PNORM positive normalized non-zero
HAS_FP_CLASS
This symbol, if defined, indicates that the fp_class
routine is available to classify doubles. Available for example in Digital UNIX
. The returned values are defined in math.h and are:
FP_SNAN Signaling NaN (Not-a-Number)
FP_QNAN Quiet NaN (Not-a-Number)
FP_POS_INF +infinity
FP_NEG_INF -infinity
FP_POS_NORM Positive normalized
FP_NEG_NORM Negative normalized
FP_POS_DENORM Positive denormalized
FP_NEG_DENORM Negative denormalized
FP_POS_ZERO +0.0 (positive zero)
FP_NEG_ZERO -0.0 (negative zero)
HAS_FPCLASSIFY
This symbol, if defined, indicates that the fpclassify
routine is available to classify doubles. Available for example in HP-UX. The returned values are defined in math.h and are
FP_NORMAL Normalized
FP_ZERO Zero
FP_INFINITE Infinity
FP_SUBNORMAL Denormalized
FP_NAN NaN
HAS_FP_CLASSIFY
This symbol, if defined, indicates that the fp_classify
routine is available to classify doubles. The values are defined in math.h
FP_NORMAL Normalized
FP_ZERO Zero
FP_INFINITE Infinity
FP_SUBNORMAL Denormalized
FP_NAN NaN
HAS_FPCLASSL
This symbol, if defined, indicates that the fpclassl
routine is available to classify long doubles. Available for example in IRIX
. The returned values are defined in ieeefp.h and are:
FP_SNAN signaling NaN
FP_QNAN quiet NaN
FP_NINF negative infinity
FP_PINF positive infinity
FP_NDENORM negative denormalized non-zero
FP_PDENORM positive denormalized non-zero
FP_NZERO negative zero
FP_PZERO positive zero
FP_NNORM negative normalized non-zero
FP_PNORM positive normalized non-zero
HAS_FP_CLASSL
This symbol, if defined, indicates that the fp_classl
routine is available to classify long doubles. Available for example in Digital UNIX
. See for possible values HAS_FP_CLASS
.
HAS_FPGETROUND
This symbol, if defined, indicates that the fpgetround
routine is available to get the floating point rounding mode.
HAS_FREXPL
This symbol, if defined, indicates that the frexpl
routine is available to break a long double floating-point number into a normalized fraction and an integral power of 2.
HAS_ILOGB
This symbol, if defined, indicates that the ilogb
routine is available to get integer exponent of a floating-point value.
HAS_ISFINITE
This symbol, if defined, indicates that the isfinite
routine is available to check whether a double is finite (non-infinity non-NaN).
HAS_ISFINITEL
This symbol, if defined, indicates that the isfinitel
routine is available to check whether a long double is finite. (non-infinity non-NaN).
HAS_ISINF
This symbol, if defined, indicates that the isinf
routine is available to check whether a double is an infinity.
HAS_ISINFL
This symbol, if defined, indicates that the isinfl
routine is available to check whether a long double is an infinity.
HAS_ISNAN
This symbol, if defined, indicates that the isnan
routine is available to check whether a double is a NaN.
HAS_ISNANL
This symbol, if defined, indicates that the isnanl
routine is available to check whether a long double is a NaN.
HAS_ISNORMAL
This symbol, if defined, indicates that the isnormal
routine is available to check whether a double is normal (non-zero normalized).
HAS_J0L
This symbol, if defined, indicates to the C program that the j0l()
function is available for Bessel functions of the first kind of the order zero, for long doubles.
HAS_J0
This symbol, if defined, indicates to the C program that the j0()
function is available for Bessel functions of the first kind of the order zero, for doubles.
HAS_LDBL_DIG
This symbol, if defined, indicates that this system's float.h or limits.h defines the symbol LDBL_DIG
, which is the number of significant digits in a long double precision number. Unlike for DBL_DIG
, there's no good guess for LDBL_DIG
if it is undefined.
HAS_LDEXPL
This symbol, if defined, indicates that the ldexpl
routine is available to shift a long double floating-point number by an integral power of 2.
HAS_LLRINT
This symbol, if defined, indicates that the llrint
routine is available to return the long long value closest to a double (according to the current rounding mode).
HAS_LLRINTL
This symbol, if defined, indicates that the llrintl
routine is available to return the long long value closest to a long double (according to the current rounding mode).
HAS_LLROUNDL
This symbol, if defined, indicates that the llroundl
routine is available to return the nearest long long value away from zero of the long double argument value.
HAS_LONG_DOUBLE
This symbol will be defined if the C compiler supports long doubles.
HAS_LRINT
This symbol, if defined, indicates that the lrint
routine is available to return the integral value closest to a double (according to the current rounding mode).
HAS_LRINTL
This symbol, if defined, indicates that the lrintl
routine is available to return the integral value closest to a long double (according to the current rounding mode).
HAS_LROUNDL
This symbol, if defined, indicates that the lroundl
routine is available to return the nearest integral value away from zero of the long double argument value.
HAS_MODFL
This symbol, if defined, indicates that the modfl
routine is available to split a long double x into a fractional part f and an integer part i such that |f| < 1.0 and (f + i) = x.
HAS_NAN
This symbol, if defined, indicates that the nan
routine is available to generate NaN.
HAS_NEXTTOWARD
This symbol, if defined, indicates that the nexttoward
routine is available to return the next machine representable long double from x in direction y.
HAS_REMAINDER
This symbol, if defined, indicates that the remainder
routine is available to return the floating-point remainder
.
HAS_SCALBN
This symbol, if defined, indicates that the scalbn
routine is available to multiply floating-point number by integral power of radix.
HAS_SIGNBIT
This symbol, if defined, indicates that the signbit
routine is available to check if the given number has the sign bit set. This should include correct testing of -0.0. This will only be set if the signbit()
routine is safe to use with the NV type used internally in perl. Users should call Perl_signbit()
, which will be #defined to the system's signbit()
function or macro if this symbol is defined.
HAS_SQRTL
This symbol, if defined, indicates that the sqrtl
routine is available to do long double square roots.
HAS_STRTOD_L
This symbol, if defined, indicates that the strtod_l
routine is available to convert strings to long doubles.
HAS_STRTOLD
This symbol, if defined, indicates that the strtold
routine is available to convert strings to long doubles.
HAS_STRTOLD_L
This symbol, if defined, indicates that the strtold_l
routine is available to convert strings to long doubles.
HAS_TRUNC
This symbol, if defined, indicates that the trunc
routine is available to round doubles towards zero.
HAS_UNORDERED
This symbol, if defined, indicates that the unordered
routine is available to check whether two doubles are unordered
(effectively: whether either of them is NaN)
I_FENV
This symbol, if defined, indicates to the C program that it should include fenv.h to get the floating point environment definitions.
#ifdef I_FENV
#include <fenv.h>
#endif
I_QUADMATH
This symbol, if defined, indicates that quadmath.h exists and should be included.
#ifdef I_QUADMATH
#include <quadmath.h>
#endif
LONGDBLINFBYTES
This symbol, if defined, is a comma-separated list of hexadecimal bytes for the long double precision infinity.
LONGDBLMANTBITS
This symbol, if defined, tells how many mantissa bits there are in long double precision floating point format. Note that this can be LDBL_MANT_DIG
minus one, since LDBL_MANT_DIG
can include the IEEE
754 implicit bit. The common x86-style 80-bit long double does not have an implicit bit.
LONGDBLNANBYTES
This symbol, if defined, is a comma-separated list of hexadecimal bytes (0xHH) for the long double precision not-a-number.
LONG_DOUBLEKIND
LONG_DOUBLEKIND
will be one of LONG_DOUBLE_IS_DOUBLE
LONG_DOUBLE_IS_IEEE_754_128_BIT_LITTLE_ENDIAN
LONG_DOUBLE_IS_IEEE_754_128_BIT_BIG_ENDIAN
LONG_DOUBLE_IS_X86_80_BIT_LITTLE_ENDIAN
LONG_DOUBLE_IS_X86_80_BIT_BIG_ENDIAN
LONG_DOUBLE_IS_DOUBLEDOUBLE_128_BIT_LE_LE
LONG_DOUBLE_IS_DOUBLEDOUBLE_128_BIT_BE_BE
LONG_DOUBLE_IS_DOUBLEDOUBLE_128_BIT_LE_BE
LONG_DOUBLE_IS_DOUBLEDOUBLE_128_BIT_BE_LE
LONG_DOUBLE_IS_DOUBLEDOUBLE_128_BIT_LITTLE_ENDIAN
LONG_DOUBLE_IS_DOUBLEDOUBLE_128_BIT_BIG_ENDIAN
LONG_DOUBLE_IS_VAX_H_FLOAT
LONG_DOUBLE_IS_UNKNOWN_FORMAT
It is only defined if the system supports long doubles.
LONG_DOUBLESIZE
This symbol contains the size of a long double, so that the C preprocessor can make decisions based on it. It is only defined if the system supports long doubles. Note that this is sizeof(long double)
, which may include unused bytes.
LONG_DOUBLE_STYLE_IEEE
This symbol, if defined, indicates that the long double is any of the IEEE
754 style long doubles: LONG_DOUBLE_STYLE_IEEE_STD
, LONG_DOUBLE_STYLE_IEEE_EXTENDED
, LONG_DOUBLE_STYLE_IEEE_DOUBLEDOUBLE
.
LONG_DOUBLE_STYLE_IEEE_DOUBLEDOUBLE
This symbol, if defined, indicates that the long double is the 128-bit double-double.
LONG_DOUBLE_STYLE_IEEE_EXTENDED
This symbol, if defined, indicates that the long double is the 80-bit IEEE
754. Note that despite the 'extended' this is less than the 'std', since this is an extension of the double precision.
LONG_DOUBLE_STYLE_IEEE_STD
This symbol, if defined, indicates that the long double is the 128-bit IEEE
754.
LONG_DOUBLE_STYLE_VAX
This symbol, if defined, indicates that the long double is the 128-bit VAX
format H.
NVMANTBITS
This symbol, if defined, tells how many mantissa bits (not including implicit bit) there are in a Perl NV. This depends on which floating point type was chosen.
NV_OVERFLOWS_INTEGERS_AT
This symbol gives the largest integer value that NVs can hold. This value + 1.0 cannot be stored accurately. It is expressed as constant floating point expression to reduce the chance of decimal/binary conversion issues. If it can not be determined, the value 0 is given.
NV_PRESERVES_UV
This symbol, if defined, indicates that a variable of type NVTYPE
can preserve all the bits of a variable of type UVTYPE
.
NV_PRESERVES_UV_BITS
This symbol contains the number of bits a variable of type NVTYPE
can preserve of a variable of type UVTYPE
.
NVSIZE
This symbol contains the sizeof(NV)
. Note that some floating point formats have unused bytes. The most notable example is the x86* 80-bit extended precision which comes in byte sizes of 12 and 16 (for 32 and 64 bit platforms, respectively), but which only uses 10 bytes. Perl compiled with -Duselongdouble
on x86* is like this.
NVTYPE
This symbol defines the C type used for Perl's NV.
NV_ZERO_IS_ALLBITS_ZERO
This symbol, if defined, indicates that a variable of type NVTYPE
stores 0.0 in memory as all bits zero.
This section contains configuration information not otherwise found in the more specialized sections of this document. At the end is a list of #defines
whose name should be enough to tell you what they do, and a list of #defines which tell you if you need to #include
files to get the corresponding functionality.
ASCIIish
A preprocessor symbol that is defined iff the system is an ASCII platform; this symbol would not be defined on "EBCDIC"
platforms.
#ifdef ASCIIish
BYTEORDER
This symbol holds the hexadecimal constant defined in byteorder, in a UV, i.e. 0x1234 or 0x4321 or 0x12345678, etc... If the compiler supports cross-compiling or multiple-architecture binaries, use compiler-defined macros to determine the byte order.
CHARBITS
This symbol contains the size of a char, so that the C preprocessor can make decisions based on it.
DB_VERSION_MAJOR_CFG
This symbol, if defined, defines the major version number of Berkeley DB found in the db.h header when Perl was configured.
DB_VERSION_MINOR_CFG
This symbol, if defined, defines the minor version number of Berkeley DB found in the db.h header when Perl was configured. For DB version 1 this is always 0.
DB_VERSION_PATCH_CFG
This symbol, if defined, defines the patch version number of Berkeley DB found in the db.h header when Perl was configured. For DB version 1 this is always 0.
DEFAULT_INC_EXCLUDES_DOT
This symbol, if defined, removes the legacy default behavior of including '.' at the end of @INC
.
DLSYM_NEEDS_UNDERSCORE
This symbol, if defined, indicates that we need to prepend an underscore to the symbol name before calling dlsym()
. This only makes sense if you *have* dlsym, which we will presume is the case if you're using dl_dlopen.xs.
EBCDIC
This symbol, if defined, indicates that this system uses EBCDIC
encoding.
HAS_CSH
This symbol, if defined, indicates that the C-shell exists.
HAS_GETHOSTNAME
This symbol, if defined, indicates that the C program may use the gethostname()
routine to derive the host name. See also "HAS_UNAME"
and "PHOSTNAME"
.
HAS_GNULIBC
This symbol, if defined, indicates to the C program that the GNU
C library is being used. A better check is to use the __GLIBC__
and __GLIBC_MINOR__
symbols supplied with glibc.
HAS_LGAMMA
This symbol, if defined, indicates that the lgamma
routine is available to do the log gamma function. See also "HAS_TGAMMA"
and "HAS_LGAMMA_R"
.
HAS_LGAMMA_R
This symbol, if defined, indicates that the lgamma_r
routine is available to do the log gamma function without using the global signgam variable.
HAS_NON_INT_BITFIELDS
This symbol, if defined, indicates that the C compiler accepts, without error or warning, struct bitfields
that are declared with sizes other than plain 'int'; for example 'unsigned char' is accepted.
HAS_PRCTL_SET_NAME
This symbol, if defined, indicates that the prctl routine is available to set process title and supports PR_SET_NAME
.
HAS_PROCSELFEXE
This symbol is defined if PROCSELFEXE_PATH
is a symlink to the absolute pathname of the executing program.
HAS_PSEUDOFORK
This symbol, if defined, indicates that an emulation of the fork routine is available.
HAS_REGCOMP
This symbol, if defined, indicates that the regcomp()
routine is available to do some regular pattern matching (usually on POSIX
.2 conforming systems).
HAS_SETPGID
This symbol, if defined, indicates that the setpgid(pid, gpid)
routine is available to set process group ID.
HAS_SIGSETJMP
This variable indicates to the C program that the sigsetjmp()
routine is available to save the calling process's registers and stack environment for later use by siglongjmp()
, and to optionally save the process's signal mask. See "Sigjmp_buf"
, "Sigsetjmp"
, and "Siglongjmp"
.
HAS_STRUCT_CMSGHDR
This symbol, if defined, indicates that the struct cmsghdr
is supported.
HAS_STRUCT_MSGHDR
This symbol, if defined, indicates that the struct msghdr
is supported.
HAS_TGAMMA
This symbol, if defined, indicates that the tgamma
routine is available to do the gamma function. See also "HAS_LGAMMA"
.
HAS_UNAME
This symbol, if defined, indicates that the C program may use the uname()
routine to derive the host name. See also "HAS_GETHOSTNAME"
and "PHOSTNAME"
.
HAS_UNION_SEMUN
This symbol, if defined, indicates that the union semun
is defined by including sys/sem.h. If not, the user code probably needs to define it as:
union semun {
int val;
struct semid_ds *buf;
unsigned short *array;
}
I_DIRENT
This symbol, if defined, indicates to the C program that it should include dirent.h. Using this symbol also triggers the definition of the Direntry_t
define which ends up being 'struct dirent
' or 'struct direct
' depending on the availability of dirent.h.
#ifdef I_DIRENT
#include <dirent.h>
#endif
I_POLL
This symbol, if defined, indicates that poll.h exists and should be included. (see also "HAS_POLL"
)
#ifdef I_POLL
#include <poll.h>
#endif
I_SYS_RESOURCE
This symbol, if defined, indicates to the C program that it should include sys/resource.h.
#ifdef I_SYS_RESOURCE
#include <sys_resource.h>
#endif
LIBM_LIB_VERSION
This symbol, if defined, indicates that libm exports _LIB_VERSION
and that math.h defines the enum to manipulate it.
NEED_VA_COPY
This symbol, if defined, indicates that the system stores the variable argument list datatype, va_list
, in a format that cannot be copied by simple assignment, so that some other means must be used when copying is required. As such systems vary in their provision (or non-provision) of copying mechanisms, handy.h defines a platform- independent macro, Perl_va_copy(src, dst)
, to do the job.
OSNAME
This symbol contains the name of the operating system, as determined by Configure. You shouldn't rely on it too much; the specific feature tests from Configure are generally more reliable.
OSVERS
This symbol contains the version of the operating system, as determined by Configure. You shouldn't rely on it too much; the specific feature tests from Configure are generally more reliable.
PERL_USE_GCC_BRACE_GROUPS
This C pre-processor value, if defined, indicates that it is permissible to use the GCC brace groups extension. However, use of this extension is DISCOURAGED. Use a static inline
function instead.
The extension, of the form
({ statement ... })
turns the block consisting of statement ... into an expression with a value, unlike plain C language blocks. This can present optimization possibilities, BUT, unless you know for sure that this will never be compiled without this extension being available and not forbidden, you need to specify an alternative. Thus two code paths have to be maintained, which can get out-of-sync. All these issues are solved by using a static inline
function instead.
Perl can be configured to not use this feature by passing the parameter -Accflags=-DPERL_GCC_BRACE_GROUPS_FORBIDDEN
to Configure.
#ifdef PERL_USE_GCC_BRACE_GROUPS
PHOSTNAME
This symbol, if defined, indicates the command to feed to the popen()
routine to derive the host name. See also "HAS_GETHOSTNAME"
and "HAS_UNAME"
. Note that the command uses a fully qualified path, so that it is safe even if used by a process with super-user privileges.
PROCSELFEXE_PATH
If HAS_PROCSELFEXE
is defined this symbol is the filename of the symbolic link pointing to the absolute pathname of the executing program.
PTRSIZE
This symbol contains the size of a pointer, so that the C preprocessor can make decisions based on it. It will be sizeof(void *)
if the compiler supports (void *); otherwise it will be sizeof(char *)
.
RANDBITS
This symbol indicates how many bits are produced by the function used to generate normalized random numbers. Values include 15, 16, 31, and 48.
SELECT_MIN_BITS
This symbol holds the minimum number of bits operated by select. That is, if you do select(n, ...)
, how many bits at least will be cleared in the masks if some activity is detected. Usually this is either n or 32*ceil(n/32)
, especially many little-endians do the latter. This is only useful if you have select()
, naturally.
SETUID_SCRIPTS_ARE_SECURE_NOW
This symbol, if defined, indicates that the bug that prevents setuid scripts from being secure is not present in this kernel.
ST_DEV_SIGN
This symbol holds the signedness of struct stat
's st_dev
. 1 for unsigned, -1 for signed.
ST_DEV_SIZE
This variable contains the size of struct stat
's st_dev
in bytes.
HAS_foo
symbolsThis is a list of those symbols that dont appear elsewhere in ths document that indicate if the current platform has a certain capability. Their names all begin with HAS_
. Only those symbols whose capability is directly derived from the name are listed here. All others have their meaning expanded out elsewhere in this document. This (relatively) compact list is because we think that the expansion would add little or no value and take up a lot of space (because there are so many). If you think certain ones should be expanded, send email to perl5-porters@perl.org.
Each symbol here will be #define
d if and only if the platform has the capability. If you need more detail, see the corresponding entry in config.h. For convenience, the list is split so that the ones that indicate there is a reentrant version of a capability are listed separately
HAS_ACCEPT4
, HAS_ACCESS
, HAS_ACCESSX
, HAS_ACOSH
, HAS_AINTL
, HAS_ALARM
, HAS_ASINH
, HAS_ATANH
, HAS_ATOLL
, HAS_CBRT
, HAS_CHOWN
, HAS_CHROOT
, HAS_CHSIZE
, HAS_CLEARENV
, HAS_COPYSIGN
, HAS_COPYSIGNL
, HAS_CRYPT
, HAS_CTERMID
, HAS_CUSERID
, HAS_DIRFD
, HAS_DLADDR
, HAS_DLERROR
, HAS_EACCESS
, HAS_ENDHOSTENT
, HAS_ENDNETENT
, HAS_ENDPROTOENT
, HAS_ENDSERVENT
, HAS_ERF
, HAS_ERFC
, HAS_EXPM1
, HAS_EXP2
, HAS_FCHMOD
, HAS_FCHMODAT
, HAS_FCHOWN
, HAS_FDIM
, HAS_FD_SET
, HAS_FEGETROUND
, HAS_FFS
, HAS_FFSL
, HAS_FGETPOS
, HAS_FLOCK
, HAS_FMA
, HAS_FMAX
, HAS_FMIN
, HAS_FORK
, HAS_FSEEKO
, HAS_FSETPOS
, HAS_FSYNC
, HAS_FTELLO
, HAS__FWALK
, HAS_GAI_STRERROR
, HAS_GETADDRINFO
, HAS_GETCWD
, HAS_GETESPWNAM
, HAS_GETGROUPS
, HAS_GETHOSTBYADDR
, HAS_GETHOSTBYNAME
, HAS_GETHOSTENT
, HAS_GETLOGIN
, HAS_GETNAMEINFO
, HAS_GETNETBYADDR
, HAS_GETNETBYNAME
, HAS_GETNETENT
, HAS_GETPAGESIZE
, HAS_GETPGID
, HAS_GETPGRP
, HAS_GETPGRP2
, HAS_GETPPID
, HAS_GETPRIORITY
, HAS_GETPROTOBYNAME
, HAS_GETPROTOBYNUMBER
, HAS_GETPROTOENT
, HAS_GETPRPWNAM
, HAS_GETSERVBYNAME
, HAS_GETSERVBYPORT
, HAS_GETSERVENT
, HAS_GETSPNAM
, HAS_HTONL
, HAS_HTONS
, HAS_HYPOT
, HAS_ILOGBL
, HAS_INET_ATON
, HAS_INETNTOP
, HAS_INETPTON
, HAS_IP_MREQ
, HAS_IP_MREQ_SOURCE
, HAS_IPV6_MREQ
, HAS_IPV6_MREQ_SOURCE
, HAS_ISASCII
, HAS_ISBLANK
, HAS_ISLESS
, HAS_KILLPG
, HAS_LCHOWN
, HAS_LINK
, HAS_LINKAT
, HAS_LLROUND
, HAS_LOCKF
, HAS_LOGB
, HAS_LOG1P
, HAS_LOG2
, HAS_LROUND
, HAS_LSTAT
, HAS_MADVISE
, HAS_MBLEN
, HAS_MBRLEN
, HAS_MBRTOWC
, HAS_MBSTOWCS
, HAS_MBTOWC
, HAS_MEMMEM
, HAS_MEMRCHR
, HAS_MKDTEMP
, HAS_MKFIFO
, HAS_MKOSTEMP
, HAS_MKSTEMP
, HAS_MKSTEMPS
, HAS_MMAP
, HAS_MPROTECT
, HAS_MSG
, HAS_MSYNC
, HAS_MUNMAP
, HAS_NEARBYINT
, HAS_NEXTAFTER
, HAS_NICE
, HAS_NTOHL
, HAS_NTOHS
, HAS_PATHCONF
, HAS_PAUSE
, HAS_PHOSTNAME
, HAS_PIPE
, HAS_PIPE2
, HAS_PRCTL
, HAS_PTRDIFF_T
, HAS_READLINK
, HAS_READV
, HAS_RECVMSG
, HAS_REMQUO
, HAS_RENAME
, HAS_RENAMEAT
, HAS_RINT
, HAS_ROUND
, HAS_SCALBNL
, HAS_SEM
, HAS_SENDMSG
, HAS_SETEGID
, HAS_SETENV
, HAS_SETEUID
, HAS_SETGROUPS
, HAS_SETHOSTENT
, HAS_SETLINEBUF
, HAS_SETNETENT
, HAS_SETPGRP
, HAS_SETPGRP2
, HAS_SETPRIORITY
, HAS_SETPROCTITLE
, HAS_SETPROTOENT
, HAS_SETREGID
, HAS_SETRESGID
, HAS_SETRESUID
, HAS_SETREUID
, HAS_SETRGID
, HAS_SETRUID
, HAS_SETSERVENT
, HAS_SETSID
, HAS_SHM
, HAS_SIGACTION
, HAS_SIGPROCMASK
, HAS_SIN6_SCOPE_ID
, HAS_SNPRINTF
, HAS_STAT
, HAS_STRCOLL
, HAS_STRERROR_L
, HAS_STRLCAT
, HAS_STRLCPY
, HAS_STRNLEN
, HAS_STRTOD
, HAS_STRTOL
, HAS_STRTOLL
, HAS_STRTOQ
, HAS_STRTOUL
, HAS_STRTOULL
, HAS_STRTOUQ
, HAS_STRXFRM
, HAS_STRXFRM_L
, HAS_SYMLINK
, HAS_SYSCALL
, HAS_SYSCONF
, HAS_SYS_ERRLIST
, HAS_SYSTEM
, HAS_TCGETPGRP
, HAS_TCSETPGRP
, HAS_TOWLOWER
, HAS_TOWUPPER
, HAS_TRUNCATE
, HAS_TRUNCL
, HAS_UALARM
, HAS_UMASK
, HAS_UNLINKAT
, HAS_UNSETENV
, HAS_VFORK
, HAS_VSNPRINTF
, HAS_WAITPID
, HAS_WAIT4
, HAS_WCRTOMB
, HAS_WCSCMP
, HAS_WCSTOMBS
, HAS_WCSXFRM
, HAS_WCTOMB
, HAS_WRITEV
And, the reentrant capabilities:
HAS_CRYPT_R
, HAS_CTERMID_R
, HAS_DRAND48_R
, HAS_ENDHOSTENT_R
, HAS_ENDNETENT_R
, HAS_ENDPROTOENT_R
, HAS_ENDSERVENT_R
, HAS_GETGRGID_R
, HAS_GETGRNAM_R
, HAS_GETHOSTBYADDR_R
, HAS_GETHOSTBYNAME_R
, HAS_GETHOSTENT_R
, HAS_GETLOGIN_R
, HAS_GETNETBYADDR_R
, HAS_GETNETBYNAME_R
, HAS_GETNETENT_R
, HAS_GETPROTOBYNAME_R
, HAS_GETPROTOBYNUMBER_R
, HAS_GETPROTOENT_R
, HAS_GETPWNAM_R
, HAS_GETPWUID_R
, HAS_GETSERVBYNAME_R
, HAS_GETSERVBYPORT_R
, HAS_GETSERVENT_R
, HAS_GETSPNAM_R
, HAS_RANDOM_R
, HAS_READDIR_R
, HAS_SETHOSTENT_R
, HAS_SETNETENT_R
, HAS_SETPROTOENT_R
, HAS_SETSERVENT_R
, HAS_SRANDOM_R
, HAS_SRAND48_R
, HAS_STRERROR_R
, HAS_TMPNAM_R
, HAS_TTYNAME_R
Example usage:
#ifdef HAS_STRNLEN
use strnlen()
#else
use an alternative implementation
#endif
#include
needed symbolsThis list contains symbols that indicate if certain #include
files are present on the platform. If your code accesses the functionality that one of these is for, you will need to #include
it if the symbol on this list is #define
d. For more detail, see the corresponding entry in config.h.
I_ARPA_INET
, I_BFD
, I_CRYPT
, I_DBM
, I_DLFCN
, I_EXECINFO
, I_FP
, I_FP_CLASS
, I_GDBM
, I_GDBMNDBM
, I_GDBM_NDBM
, I_GRP
, I_IEEEFP
, I_INTTYPES
, I_LIBUTIL
, I_MNTENT
, I_NDBM
, I_NETDB
, I_NET_ERRNO
, I_NETINET_IN
, I_NETINET_TCP
, I_PROT
, I_PWD
, I_RPCSVC_DBM
, I_SGTTY
, I_SHADOW
, I_STDBOOL
, I_STDINT
, I_SUNMATH
, I_SYS_ACCESS
, I_SYS_IOCTL
, I_SYSLOG
, I_SYSMODE
, I_SYS_MOUNT
, I_SYS_PARAM
, I_SYS_POLL
, I_SYS_SECURITY
, I_SYS_SELECT
, I_SYS_STAT
, I_SYS_STATVFS
, I_SYS_SYSCALL
, I_SYS_TIME
, I_SYS_TIME_KERNEL
, I_SYS_TIMES
, I_SYS_TYPES
, I_SYSUIO
, I_SYS_UN
, I_SYSUTSNAME
, I_SYS_VFS
, I_SYS_WAIT
, I_TERMIO
, I_TERMIOS
, I_UNISTD
, I_USTAT
, I_VFORK
, I_WCHAR
, I_WCTYPE
Example usage:
#ifdef I_WCHAR
#include <wchar.h>
#endif
These variables are global to an entire process. They are shared between all interpreters and all threads in a process. Any variables not documented here may be changed or removed without notice, so don't use them! If you feel you really do need to use an unlisted variable, first send email to perl5-porters@perl.org. It may be that someone there will point out a way to accomplish what you need without using an internal variable. But if not, you should get a go-ahead to document and then use the variable.
PL_check
Array, indexed by opcode, of functions that will be called for the "check" phase of optree building during compilation of Perl code. For most (but not all) types of op, once the op has been initially built and populated with child ops it will be filtered through the check function referenced by the appropriate element of this array. The new op is passed in as the sole argument to the check function, and the check function returns the completed op. The check function may (as the name suggests) check the op for validity and signal errors. It may also initialise or modify parts of the ops, or perform more radical surgery such as adding or removing child ops, or even throw the op away and return a different op in its place.
This array of function pointers is a convenient place to hook into the compilation process. An XS module can put its own custom check function in place of any of the standard ones, to influence the compilation of a particular type of op. However, a custom check function must never fully replace a standard check function (or even a custom check function from another module). A module modifying checking must instead wrap the preexisting check function. A custom check function must be selective about when to apply its custom behaviour. In the usual case where it decides not to do anything special with an op, it must chain the preexisting op function. Check functions are thus linked in a chain, with the core's base checker at the end.
For thread safety, modules should not write directly to this array. Instead, use the function "wrap_op_checker".
PL_infix_plugin
NOTE: PL_infix_plugin
is experimental and may change or be removed without notice.
NOTE: This API exists entirely for the purpose of making the CPAN module XS::Parse::Infix
work. It is not expected that additional modules will make use of it; rather, that they should use XS::Parse::Infix
to provide parsing of new infix operators.
Function pointer, pointing at a function used to handle extended infix operators. The function should be declared as
int infix_plugin_function(pTHX_
char *opname, STRLEN oplen,
struct Perl_custom_infix **infix_ptr)
The function is called from the tokenizer whenever a possible infix operator is seen. opname
points to the operator name in the parser's input buffer, and oplen
gives the maximum number of bytes of it that should be consumed; it is not null-terminated. The function is expected to examine the operator name and possibly other state such as %^H, to determine whether it wants to handle the operator name.
As compared to the single stage of PL_keyword_plugin
, parsing of additional infix operators occurs in three separate stages. This is because of the more complex interactions it has with the parser, to ensure that operator precedence rules work correctly. These stages are co-ordinated by the use of an additional information structure.
If the function wants to handle the infix operator, it must set the variable pointed to by infix_ptr
to the address of a structure that provides this additional information about the subsequent parsing stages. If it does not, it should make a call to the next function in the chain.
This structure has the following definition:
struct Perl_custom_infix {
enum Perl_custom_infix_precedence prec;
void (*parse)(pTHX_ SV **opdata,
struct Perl_custom_infix *);
OP *(*build_op)(pTHX_ SV **opdata, OP *lhs, OP *rhs,
struct Perl_custom_infix *);
};
The function must then return an integer giving the number of bytes consumed by the name of this operator. In the case of an operator whose name is composed of identifier characters, this must be equal to oplen
. In the case of an operator named by non-identifier characters, this is permitted to be shorter than oplen
, and any additional characters after it will not be claimed by the infix operator but instead will be consumed by the tokenizer and parser as normal.
If the optional parse
function is provided, it is called immediately by the parser to let the operator's definition consume any additional syntax from the source code. This should not be used for normal operand parsing, but it may be useful when implementing things like parametric operators or meta-operators that consume more syntax themselves. This function may use the variable pointed to by opdata
to provide an SV containing additional data to be passed into the build_op
function later on.
The information structure gives the operator precedence level in the prec
field. This is used to tell the parser how much of the surrounding syntax before and after should be considered as operands to the operator.
The tokenizer and parser will then continue to operate as normal until enough additional input has been parsed to form both the left- and right-hand side operands to the operator, according to the precedence level. At this point the build_op
function is called, being passed the left- and right-hand operands as optree fragments. It is expected to combine them into the resulting optree fragment, which it should return.
After the build_op
function has returned, if the variable pointed to by opdata
was set to a non-NULL
value, it will then be destroyed by calling SvREFCNT_dec()
.
For thread safety, modules should not set this variable directly. Instead, use the function "wrap_infix_plugin".
However, that all said, the introductory note above still applies. This variable is provided in core perl only for the benefit of the XS::Parse::Infix
module. That module acts as a central registry for infix operators, automatically handling things like deparse support and discovery/reflection, and these abilities only work because it knows all the registered operators. Other modules should not use this interpreter variable directly to implement them because then those central features would no longer work properly.
Furthermore, it is likely that this (experimental) API will be replaced in a future Perl version by a more complete API that fully implements the central registry and other semantics currently provided by XS::Parse::Infix
, once the module has had sufficient experimental testing time. This current mechanism exists only as an interim measure to get to that stage.
PL_keyword_plugin
NOTE: PL_keyword_plugin
is experimental and may change or be removed without notice.
Function pointer, pointing at a function used to handle extended keywords. The function should be declared as
int keyword_plugin_function(pTHX_
char *keyword_ptr, STRLEN keyword_len,
OP **op_ptr)
The function is called from the tokeniser, whenever a possible keyword is seen. keyword_ptr
points at the word in the parser's input buffer, and keyword_len
gives its length; it is not null-terminated. The function is expected to examine the word, and possibly other state such as %^H, to decide whether it wants to handle it as an extended keyword. If it does not, the function should return KEYWORD_PLUGIN_DECLINE
, and the normal parser process will continue.
If the function wants to handle the keyword, it first must parse anything following the keyword that is part of the syntax introduced by the keyword. See "Lexer interface" for details.
When a keyword is being handled, the plugin function must build a tree of OP
structures, representing the code that was parsed. The root of the tree must be stored in *op_ptr
. The function then returns a constant indicating the syntactic role of the construct that it has parsed: KEYWORD_PLUGIN_STMT
if it is a complete statement, or KEYWORD_PLUGIN_EXPR
if it is an expression. Note that a statement construct cannot be used inside an expression (except via do BLOCK
and similar), and an expression is not a complete statement (it requires at least a terminating semicolon).
When a keyword is handled, the plugin function may also have (compile-time) side effects. It may modify %^H
, define functions, and so on. Typically, if side effects are the main purpose of a handler, it does not wish to generate any ops to be included in the normal compilation. In this case it is still required to supply an op tree, but it suffices to generate a single null op.
That's how the *PL_keyword_plugin
function needs to behave overall. Conventionally, however, one does not completely replace the existing handler function. Instead, take a copy of PL_keyword_plugin
before assigning your own function pointer to it. Your handler function should look for keywords that it is interested in and handle those. Where it is not interested, it should call the saved plugin function, passing on the arguments it received. Thus PL_keyword_plugin
actually points at a chain of handler functions, all of which have an opportunity to handle keywords, and only the last function in the chain (built into the Perl core) will normally return KEYWORD_PLUGIN_DECLINE
.
For thread safety, modules should not set this variable directly. Instead, use the function "wrap_keyword_plugin".
PL_phase
A value that indicates the current Perl interpreter's phase. Possible values include PERL_PHASE_CONSTRUCT
, PERL_PHASE_START
, PERL_PHASE_CHECK
, PERL_PHASE_INIT
, PERL_PHASE_RUN
, PERL_PHASE_END
, and PERL_PHASE_DESTRUCT
.
For example, the following determines whether the interpreter is in global destruction:
if (PL_phase == PERL_PHASE_DESTRUCT) {
// we are in global destruction
}
PL_phase
was introduced in Perl 5.14; in prior perls you can use PL_dirty
(boolean) to determine whether the interpreter is in global destruction. (Use of PL_dirty
is discouraged since 5.14.)
enum perl_phase PL_phase
A GV is a structure which corresponds to a Perl typeglob, ie *foo. It is a structure that holds a pointer to a scalar, an array, a hash etc, corresponding to $foo, @foo, %foo.
GVs are usually found as values in stashes (symbol table hashes) where Perl stores its global variables.
A stash is a hash that contains all variables that are defined within a package. See "Stashes and Globs" in perlguts
amagic_call
Perform the overloaded (active magic) operation given by method
. method
is one of the values found in overload.h.
flags
affects how the operation is performed, as follows:
AMGf_noleft
left
is not to be used in this operation.
AMGf_noright
right
is not to be used in this operation.
AMGf_unary
The operation is done only on just one operand.
AMGf_assign
The operation changes one of the operands, e.g., $x += 1
SV * amagic_call(SV *left, SV *right, int method, int dir)
amagic_deref_call
Perform method
overloading dereferencing on ref
, returning the dereferenced result. method
must be one of the dereference operations given in overload.h.
If overloading is inactive on ref
, returns ref
itself.
SV * amagic_deref_call(SV *ref, int method)
gv_add_by_type
Make sure there is a slot of type type
in the GV gv
.
GV * gv_add_by_type(GV *gv, svtype type)
Gv_AMupdate
Recalculates overload magic in the package given by stash
.
Returns:
destructing
is true).int Gv_AMupdate(HV *stash, bool destructing)
gv_autoload_pv
gv_autoload_pvn
gv_autoload_sv
These each search for an AUTOLOAD
method, returning NULL if not found, or else returning a pointer to its GV, while setting the package $AUTOLOAD
variable to name
(fully qualified). Also, if found and the GV's CV is an XSUB, the CV's PV will be set to name
, and its stash will be set to the stash of the GV.
Searching is done in MRO
order, as specified in "gv_fetchmeth
", beginning with stash
if it isn't NULL.
The forms differ only in how name
is specified.
In gv_autoload_pv
, namepv
is a C language NUL-terminated string.
In gv_autoload_pvn
, name
points to the first byte of the name, and an additional parameter, len
, specifies its length in bytes. Hence, *name
may contain embedded-NUL characters.
In gv_autoload_sv
, *namesv
is an SV, and the name is the PV extracted from that using "SvPV
". If the SV is marked as being in UTF-8, the extracted PV will also be.
GV * gv_autoload_pv (HV *stash, const char *namepv, U32 flags)
GV * gv_autoload_pvn(HV *stash, const char *name, STRLEN len,
U32 flags)
GV * gv_autoload_sv (HV *stash, SV *namesv, U32 flags)
gv_autoload4
Equivalent to "gv_autoload_pvn"
.
GV * gv_autoload4(HV *stash, const char *name, STRLEN len,
I32 method)
GvAV
Return the AV from the GV.
AV* GvAV(GV* gv)
gv_AVadd
gv_HVadd
gv_IOadd
gv_SVadd
Make sure there is a slot of the given type (AV, HV, IO, SV) in the GV gv
.
GV * gv_AVadd(GV *gv)
gv_const_sv
If gv
is a typeglob whose subroutine entry is a constant sub eligible for inlining, or gv
is a placeholder reference that would be promoted to such a typeglob, then returns the value returned by the sub. Otherwise, returns NULL
.
SV * gv_const_sv(GV *gv)
GvCV
Return the CV from the GV.
CV* GvCV(GV* gv)
gv_efullname3
gv_efullname4
gv_fullname3
gv_fullname4
Place the full package name of gv
into sv
. The gv_e*
forms return instead the effective package name (see "HvENAME").
If prefix
is non-NULL, it is considered to be a C language NUL-terminated string, and the stored name will be prefaced with it.
The other difference between the functions is that the *4
forms have an extra parameter, keepmain
. If true
an initial main::
in the name is kept; if false
it is stripped. With the *3
forms, it is always kept.
void gv_efullname3(SV *sv, const GV *gv, const char *prefix)
void gv_efullname4(SV *sv, const GV *gv, const char *prefix,
bool keepmain)
void gv_fullname3 (SV *sv, const GV *gv, const char *prefix)
void gv_fullname4 (SV *sv, const GV *gv, const char *prefix,
bool keepmain)
gv_fetchfile
gv_fetchfile_flags
These return the debugger glob for the file (compiled by Perl) whose name is given by the name
parameter.
There are currently exactly two differences between these functions.
The name
parameter to gv_fetchfile
is a C string, meaning it is NUL
-terminated; whereas the name
parameter to gv_fetchfile_flags
is a Perl string, whose length (in bytes) is passed in via the namelen
parameter This means the name may contain embedded NUL
characters. namelen
doesn't exist in plain gv_fetchfile
).
The other difference is that gv_fetchfile_flags
has an extra flags
parameter, which is currently completely ignored, but allows for possible future extensions.
GV * gv_fetchfile (const char *name)
GV * gv_fetchfile_flags(const char * const name,
const STRLEN len, const U32 flags)
gv_fetchmeth
gv_fetchmeth_pv
gv_fetchmeth_pvn
gv_fetchmeth_sv
These each look for a glob with name name
, containing a defined subroutine, returning the GV of that glob if found, or NULL
if not.
stash
is always searched (first), unless it is NULL
.
If stash
is NULL, or was searched but nothing was found in it, and the GV_SUPER
bit is set in flags
, stashes accessible via @ISA
are searched next. Searching is conducted according to MRO
order.
Finally, if no matches were found so far, and the GV_NOUNIVERSAL
flag in flags
is not set, UNIVERSAL::
is searched.
The argument level
should be either 0 or -1. If -1, the function will return without any side effects or caching. If 0, the function makes sure there is a glob named name
in stash
, creating one if necessary. The subroutine slot in the glob will be set to any subroutine found in the stash
and SUPER::
search, hence caching any SUPER::
result. Note that subroutines found in UNIVERSAL::
are not cached.
The GV returned from these may be a method cache entry, which is not visible to Perl code. So when calling call_sv
, you should not use the GV directly; instead, you should use the method's CV, which can be obtained from the GV with the GvCV
macro.
The only other significant value for flags
is SVf_UTF8
, indicating that name
is to be treated as being encoded in UTF-8.
Plain gv_fetchmeth
lacks a flags
parameter, hence always searches in stash
, then UNIVERSAL::
, and name
is never UTF-8. Otherwise it is exactly like gv_fetchmeth_pvn
.
The other forms do have a flags
parameter, and differ only in how the glob name is specified.
In gv_fetchmeth_pv
, name
is a C language NUL-terminated string.
In gv_fetchmeth_pvn
, name
points to the first byte of the name, and an additional parameter, len
, specifies its length in bytes. Hence, the name may contain embedded-NUL characters.
In gv_fetchmeth_sv
, *name
is an SV, and the name is the PV extracted from that, using "SvPV
". If the SV is marked as being in UTF-8, the extracted PV will also be.
GV * gv_fetchmeth (HV *stash, const char *name, STRLEN len,
I32 level)
GV * gv_fetchmeth_pv (HV *stash, const char *name, I32 level,
U32 flags)
GV * gv_fetchmeth_pvn(HV *stash, const char *name, STRLEN len,
I32 level, U32 flags)
GV * gv_fetchmeth_sv (HV *stash, SV *namesv, I32 level,
U32 flags)
gv_fetchmeth_autoload
This is the old form of "gv_fetchmeth_pvn_autoload", which has no flags parameter.
GV * gv_fetchmeth_autoload(HV *stash, const char *name,
STRLEN len, I32 level)
gv_fetchmethod
See "gv_fetchmethod_autoload".
GV * gv_fetchmethod(HV *stash, const char *name)
gv_fetchmethod_autoload
Returns the glob which contains the subroutine to call to invoke the method on the stash
. In fact in the presence of autoloading this may be the glob for "AUTOLOAD". In this case the corresponding variable $AUTOLOAD
is already setup.
The third parameter of gv_fetchmethod_autoload
determines whether AUTOLOAD lookup is performed if the given method is not present: non-zero means yes, look for AUTOLOAD; zero means no, don't look for AUTOLOAD. Calling gv_fetchmethod
is equivalent to calling gv_fetchmethod_autoload
with a non-zero autoload
parameter.
These functions grant "SUPER"
token as a prefix of the method name. Note that if you want to keep the returned glob for a long time, you need to check for it being "AUTOLOAD", since at the later time the call may load a different subroutine due to $AUTOLOAD
changing its value. Use the glob created as a side effect to do this.
These functions have the same side-effects as gv_fetchmeth
with level==0
. The warning against passing the GV returned by gv_fetchmeth
to call_sv
applies equally to these functions.
GV * gv_fetchmethod_autoload(HV *stash, const char *name,
I32 autoload)
gv_fetchmeth_pv_autoload
Exactly like "gv_fetchmeth_pvn_autoload", but takes a nul-terminated string instead of a string/length pair.
GV * gv_fetchmeth_pv_autoload(HV *stash, const char *name,
I32 level, U32 flags)
gv_fetchmeth_pvn_autoload
Same as gv_fetchmeth_pvn()
, but looks for autoloaded subroutines too. Returns a glob for the subroutine.
For an autoloaded subroutine without a GV, will create a GV even if level < 0
. For an autoloaded subroutine without a stub, GvCV()
of the result may be zero.
Currently, the only significant value for flags
is SVf_UTF8
.
GV * gv_fetchmeth_pvn_autoload(HV *stash, const char *name,
STRLEN len, I32 level, U32 flags)
gv_fetchmeth_sv_autoload
Exactly like "gv_fetchmeth_pvn_autoload", but takes the name string in the form of an SV instead of a string/length pair.
GV * gv_fetchmeth_sv_autoload(HV *stash, SV *namesv, I32 level,
U32 flags)
gv_fetchpv
gv_fetchpvn
gv_fetchpvn_flags
gv_fetchpvs
gv_fetchsv
gv_fetchsv_nomg
These all return the GV of type sv_type
whose name is given by the inputs, or NULL if no GV of that name and type could be found. See "Stashes and Globs" in perlguts.
The only differences are how the input name is specified, and if 'get' magic is normally used in getting that name.
Don't be fooled by the fact that only one form has flags
in its name. They all have a flags
parameter in fact, and all the flag bits have the same meanings for all
If any of the flags GV_ADD
, GV_ADDMG
, GV_ADDWARN
, GV_ADDMULTI
, or GV_NOINIT
is set, a GV is created if none already exists for the input name and type. However, GV_ADDMG
will only do the creation for magical GV's. For all of these flags except GV_NOINIT
, "gv_init_pvn"
is called after the addition. GV_ADDWARN
is used when the caller expects that adding won't be necessary because the symbol should already exist; but if not, add it anyway, with a warning that it was unexpectedly absent. The GV_ADDMULTI
flag means to pretend that the GV has been seen before (i.e., suppress "Used once" warnings).
The flag GV_NOADD_NOINIT
causes "gv_init_pvn"
not be to called if the GV existed but isn't PVGV.
If the SVf_UTF8
bit is set, the name is treated as being encoded in UTF-8; otherwise the name won't be considered to be UTF-8 in the pv
-named forms, and the UTF-8ness of the underlying SVs will be used in the sv
forms.
If the flag GV_NOTQUAL
is set, the caller warrants that the input name is a plain symbol name, not qualified with a package, otherwise the name is checked for being a qualified one.
In gv_fetchpv
, nambeg
is a C string, NUL-terminated with no intermediate NULs.
In gv_fetchpvs
, name
is a literal C string, hence is enclosed in double quotes.
gv_fetchpvn
and gv_fetchpvn_flags
are identical. In these, <nambeg> is a Perl string whose byte length is given by full_len
, and may contain embedded NULs.
In gv_fetchsv
and gv_fetchsv_nomg
, the name is extracted from the PV of the input name
SV. The only difference between these two forms is that 'get' magic is normally done on name
in gv_fetchsv
, and always skipped with gv_fetchsv_nomg
. Including GV_NO_SVGMAGIC
in the flags
parameter to gv_fetchsv
makes it behave identically to gv_fetchsv_nomg
.
GV * gv_fetchpv (const char *nambeg, I32 flags,
const svtype sv_type)
GV * gv_fetchpvn (const char * nambeg, STRLEN full_len,
I32 flags, const svtype sv_type)
GV * gv_fetchpvn_flags(const char *name, STRLEN len, I32 flags,
const svtype sv_type)
GV * gv_fetchpvs ("name", I32 flags, const svtype sv_type)
GV * gv_fetchsv (SV *name, I32 flags, const svtype sv_type)
GV * gv_fetchsv_nomg (SV *name, I32 flags, const svtype sv_type)
GvHV
Return the HV from the GV.
HV* GvHV(GV* gv)
gv_init
The old form of gv_init_pvn()
. It does not work with UTF-8 strings, as it has no flags parameter. If the multi
parameter is set, the GV_ADDMULTI
flag will be passed to gv_init_pvn()
.
void gv_init(GV *gv, HV *stash, const char *name, STRLEN len,
int multi)
gv_init_pv
Same as gv_init_pvn()
, but takes a nul-terminated string for the name instead of separate char * and length parameters.
void gv_init_pv(GV *gv, HV *stash, const char *name, U32 flags)
gv_init_pvn
Converts a scalar into a typeglob. This is an incoercible typeglob; assigning a reference to it will assign to one of its slots, instead of overwriting it as happens with typeglobs created by SvSetSV
. Converting any scalar that is SvOK()
may produce unpredictable results and is reserved for perl's internal use.
gv
is the scalar to be converted.
stash
is the parent stash/package, if any.
name
and len
give the name. The name must be unqualified; that is, it must not include the package name. If gv
is a stash element, it is the caller's responsibility to ensure that the name passed to this function matches the name of the element. If it does not match, perl's internal bookkeeping will get out of sync.
flags
can be set to SVf_UTF8
if name
is a UTF-8 string, or the return value of SvUTF8(sv). It can also take the GV_ADDMULTI
flag, which means to pretend that the GV has been seen before (i.e., suppress "Used once" warnings).
void gv_init_pvn(GV *gv, HV *stash, const char *name, STRLEN len,
U32 flags)
gv_init_sv
Same as gv_init_pvn()
, but takes an SV * for the name instead of separate char * and length parameters. flags
is currently unused.
void gv_init_sv(GV *gv, HV *stash, SV *namesv, U32 flags)
gv_name_set
Set the name for GV gv
to name
which is len
bytes long. Thus it may contain embedded NUL characters.
If flags
contains SVf_UTF8
, the name is treated as being encoded in UTF-8; otherwise not.
void gv_name_set(GV *gv, const char *name, U32 len, U32 flags)
gv_stashpv
Returns a pointer to the stash for a specified package. Uses strlen
to determine the length of name
, then calls gv_stashpvn()
.
HV * gv_stashpv(const char *name, I32 flags)
gv_stashpvn
Returns a pointer to the stash for a specified package. The namelen
parameter indicates the length of the name
, in bytes. flags
is passed to gv_fetchpvn_flags()
, so if set to GV_ADD
then the package will be created if it does not already exist. If the package does not exist and flags
is 0 (or any other setting that does not create packages) then NULL
is returned.
Flags may be one of:
GV_ADD Create and initialize the package if doesn't
already exist
GV_NOADD_NOINIT Don't create the package,
GV_ADDMG GV_ADD iff the GV is magical
GV_NOINIT GV_ADD, but don't initialize
GV_NOEXPAND Don't expand SvOK() entries to PVGV
SVf_UTF8 The name is in UTF-8
The most important of which are probably GV_ADD
and SVf_UTF8
.
Note, use of gv_stashsv
instead of gv_stashpvn
where possible is strongly recommended for performance reasons.
HV * gv_stashpvn(const char *name, U32 namelen, I32 flags)
gv_stashpvs
Like gv_stashpvn
, but takes a literal string instead of a string/length pair.
HV* gv_stashpvs("name", I32 create)
gv_stashsv
Returns a pointer to the stash for a specified package. See "gv_stashpvn"
.
Note this interface is strongly preferred over gv_stashpvn
for performance reasons.
HV * gv_stashsv(SV *sv, I32 flags)
GvSV
Return the SV from the GV.
Prior to Perl v5.9.3, this would add a scalar if none existed. Nowadays, use "GvSVn"
for that, or compile perl with -DPERL_CREATE_GVSV
. See perl5100delta.
SV* GvSV(GV* gv)
newGVgen
newGVgen_flags
Create a new, guaranteed to be unique, GV in the package given by the NUL-terminated C language string pack
, and return a pointer to it.
For newGVgen
or if flags
in newGVgen_flags
is 0, pack
is to be considered to be encoded in Latin-1. The only other legal flags
value is SVf_UTF8
, which indicates pack
is to be considered to be encoded in UTF-8.
GV * newGVgen (const char *pack)
GV * newGVgen_flags(const char *pack, U32 flags)
PL_curstash
The stash for the package code will be compiled into.
On threaded perls, each thread has an independent copy of this variable; each initialized at creation time with the current value of the creating thread's copy.
HV* PL_curstash
PL_defgv
The GV representing *_
. Useful for access to $_
.
On threaded perls, each thread has an independent copy of this variable; each initialized at creation time with the current value of the creating thread's copy.
GV * PL_defgv
PL_defoutgv
See "setdefout"
.
save_gp
Saves the current GP of gv on the save stack to be restored on scope exit.
If empty
is true, replace the GP with a new GP.
If empty
is false, mark gv
with GVf_INTRO
so the next reference assigned is localized, which is how local *foo = $someref;
works.
void save_gp(GV *gv, I32 empty)
setdefout
Sets PL_defoutgv
, the default file handle for output, to the passed in typeglob. As PL_defoutgv
"owns" a reference on its typeglob, the reference count of the passed in typeglob is increased by one, and the reference count of the typeglob that PL_defoutgv
points to is decreased by one.
void setdefout(GV *gv)
These functions provide convenient and thread-safe means of manipulating hook variables.
rcpv_copy
refcount increment a shared memory refcounted string, and when the refcount goes to 0 free it using PerlMemShared_free().
It is the callers responsibility to ensure that the pv is the result of a rcpv_new() call.
Returns the same pointer that was passed in.
new = rcpv_copy(pv);
char * rcpv_copy(char * const pv)
rcpv_free
refcount decrement a shared memory refcounted string, and when the refcount goes to 0 free it using perlmemshared_free().
it is the callers responsibility to ensure that the pv is the result of a rcpv_new() call.
Always returns NULL so it can be used like this:
thing = rcpv_free(thing);
char * rcpv_free(char * const pv)
rcpv_new
Create a new shared memory refcounted string with the requested size, and with the requested initialization and a refcount of 1. The actual space allocated will be 1 byte more than requested and rcpv_new() will ensure that the extra byte is a null regardless of any flags settings.
If the RCPVf_NO_COPY flag is set then the pv argument will be ignored, otherwise the contents of the pv pointer will be copied into the new buffer or if it is NULL the function will do nothing and return NULL.
If the RCPVf_USE_STRLEN flag is set then the len argument is ignored and recomputed using strlen(pv)
. It is an error to combine RCPVf_USE_STRLEN and RCPVf_NO_COPY at the same time.
Under DEBUGGING rcpv_new() will assert() if it is asked to create a 0 length shared string unless the RCPVf_ALLOW_EMPTY flag is set.
The return value from the function is suitable for passing into rcpv_copy() and rcpv_free(). To access the RCPV * from the returned value use the RCPVx() macro. The 'len' member of the RCPV struct stores the allocated length (including the extra byte), but the RCPV_LEN() macro returns the requested length (not including the extra byte).
Note that rcpv_new() does NOT use a hash table or anything like that to dedupe inputs given the same text content. Each call with a non-null pv parameter will produce a distinct pointer with its own refcount regardless of the input content.
char * rcpv_new(const char * const pv, STRLEN len, U32 flags)
wrap_op_checker
Puts a C function into the chain of check functions for a specified op type. This is the preferred way to manipulate the "PL_check" array. opcode
specifies which type of op is to be affected. new_checker
is a pointer to the C function that is to be added to that opcode's check chain, and old_checker_p
points to the storage location where a pointer to the next function in the chain will be stored. The value of new_checker
is written into the "PL_check" array, while the value previously stored there is written to *old_checker_p
.
"PL_check" is global to an entire process, and a module wishing to hook op checking may find itself invoked more than once per process, typically in different threads. To handle that situation, this function is idempotent. The location *old_checker_p
must initially (once per process) contain a null pointer. A C variable of static duration (declared at file scope, typically also marked static
to give it internal linkage) will be implicitly initialised appropriately, if it does not have an explicit initialiser. This function will only actually modify the check chain if it finds *old_checker_p
to be null. This function is also thread safe on the small scale. It uses appropriate locking to avoid race conditions in accessing "PL_check".
When this function is called, the function referenced by new_checker
must be ready to be called, except for *old_checker_p
being unfilled. In a threading situation, new_checker
may be called immediately, even before this function has returned. *old_checker_p
will always be appropriately set before new_checker
is called. If new_checker
decides not to do anything special with an op that it is given (which is the usual case for most uses of op check hooking), it must chain the check function referenced by *old_checker_p
.
Taken all together, XS code to hook an op checker should typically look something like this:
static Perl_check_t nxck_frob;
static OP *myck_frob(pTHX_ OP *op) {
...
op = nxck_frob(aTHX_ op);
...
return op;
}
BOOT:
wrap_op_checker(OP_FROB, myck_frob, &nxck_frob);
If you want to influence compilation of calls to a specific subroutine, then use "cv_set_call_checker_flags" rather than hooking checking of all entersub
ops.
void wrap_op_checker(Optype opcode, Perl_check_t new_checker,
Perl_check_t *old_checker_p)
A HV structure represents a Perl hash. It consists mainly of an array of pointers, each of which points to a linked list of HE structures. The array is indexed by the hash function of the key, so each linked list represents all the hash entries with the same hash value. Each HE contains a pointer to the actual value, plus a pointer to a HEK structure which holds the key and hash value.
get_hv
Returns the HV of the specified Perl hash. flags
are passed to gv_fetchpv
. If GV_ADD
is set and the Perl variable does not exist then it will be created. If flags
is zero (ignoring SVf_UTF8
) and the variable does not exist then NULL
is returned.
NOTE: the perl_get_hv()
form is deprecated.
HV * get_hv(const char *name, I32 flags)
HEf_SVKEY
This flag, used in the length slot of hash entries and magic structures, specifies the structure contains an SV*
pointer where a char*
pointer is to be expected. (For information only--not to be used).
HeHASH
Returns the computed hash stored in the hash entry.
U32 HeHASH(HE* he)
HeKEY
Returns the actual pointer stored in the key slot of the hash entry. The pointer may be either char*
or SV*
, depending on the value of HeKLEN()
. Can be assigned to. The HePV()
or HeSVKEY()
macros are usually preferable for finding the value of a key.
void* HeKEY(HE* he)
HeKLEN
If this is negative, and amounts to HEf_SVKEY
, it indicates the entry holds an SV*
key. Otherwise, holds the actual length of the key. Can be assigned to. The HePV()
macro is usually preferable for finding key lengths.
STRLEN HeKLEN(HE* he)
HePV
Returns the key slot of the hash entry as a char*
value, doing any necessary dereferencing of possibly SV*
keys. The length of the string is placed in len
(this is a macro, so do not use &len
). If you do not care about what the length of the key is, you may use the global variable PL_na
, though this is rather less efficient than using a local variable. Remember though, that hash keys in perl are free to contain embedded nulls, so using strlen()
or similar is not a good way to find the length of hash keys. This is very similar to the SvPV()
macro described elsewhere in this document. See also "HeUTF8"
.
If you are using HePV
to get values to pass to newSVpvn()
to create a new SV, you should consider using newSVhek(HeKEY_hek(he))
as it is more efficient.
char* HePV(HE* he, STRLEN len)
HeSVKEY
Returns the key as an SV*
, or NULL
if the hash entry does not contain an SV*
key.
SV* HeSVKEY(HE* he)
HeSVKEY_force
Returns the key as an SV*
. Will create and return a temporary mortal SV*
if the hash entry contains only a char*
key.
SV* HeSVKEY_force(HE* he)
HeSVKEY_set
Sets the key to a given SV*
, taking care to set the appropriate flags to indicate the presence of an SV*
key, and returns the same SV*
.
SV* HeSVKEY_set(HE* he, SV* sv)
HeUTF8
Returns whether the char *
value returned by HePV
is encoded in UTF-8, doing any necessary dereferencing of possibly SV*
keys. The value returned will be 0 or non-0, not necessarily 1 (or even a value with any low bits set), so do not blindly assign this to a bool
variable, as bool
may be a typedef for char
.
U32 HeUTF8(HE* he)
HeVAL
Returns the value slot (type SV*
) stored in the hash entry. Can be assigned to.
SV *foo= HeVAL(hv);
HeVAL(hv)= sv;
SV* HeVAL(HE* he)
hv_assert
Check that a hash is in an internally consistent state.
NOTE: hv_assert
must be explicitly called as Perl_hv_assert
with an aTHX_
parameter.
void Perl_hv_assert(pTHX_ HV *hv)
hv_bucket_ratio
NOTE: hv_bucket_ratio
is experimental and may change or be removed without notice.
If the hash is tied dispatches through to the SCALAR tied method, otherwise if the hash contains no keys returns 0, otherwise returns a mortal sv containing a string specifying the number of used buckets, followed by a slash, followed by the number of available buckets.
This function is expensive, it must scan all of the buckets to determine which are used, and the count is NOT cached. In a large hash this could be a lot of buckets.
SV * hv_bucket_ratio(HV *hv)
hv_clear
Frees all the elements of a hash, leaving it empty. The XS equivalent of %hash = ()
. See also "hv_undef".
See "av_clear" for a note about the hash possibly being invalid on return.
void hv_clear(HV *hv)
hv_clear_placeholders
Clears any placeholders from a hash. If a restricted hash has any of its keys marked as readonly and the key is subsequently deleted, the key is not actually deleted but is marked by assigning it a value of &PL_sv_placeholder
. This tags it so it will be ignored by future operations such as iterating over the hash, but will still allow the hash to have a value reassigned to the key at some future point. This function clears any such placeholder keys from the hash. See Hash::Util::lock_keys()
for an example of its use.
void hv_clear_placeholders(HV *hv)
hv_copy_hints_hv
A specialised version of "newHVhv" for copying %^H
. ohv
must be a pointer to a hash (which may have %^H
magic, but should be generally non-magical), or NULL
(interpreted as an empty hash). The content of ohv
is copied to a new hash, which has the %^H
-specific magic added to it. A pointer to the new hash is returned.
HV * hv_copy_hints_hv(HV * const ohv)
hv_delete
hv_deletes
These delete a key/value pair in the hash. The value's SV is removed from the hash, made mortal, and returned to the caller.
In hv_deletes
, the key must be a C language string literal, enclosed in double quotes. It is never treated as being in UTF-8. There is no length_parameter.
In hv_delete
, the absolute value of klen
is the length of the key. If klen
is negative the key is assumed to be in UTF-8-encoded Unicode.
In both, the flags
value will normally be zero; if set to G_DISCARD
then NULL
will be returned. NULL
will also be returned if the key is not found.
SV * hv_delete (HV *hv, const char *key, I32 klen, I32 flags)
SV * hv_deletes(HV *hv, "key", U32 flags)
hv_delete_ent
Deletes a key/value pair in the hash. The value SV is removed from the hash, made mortal, and returned to the caller. The flags
value will normally be zero; if set to G_DISCARD
then NULL
will be returned. NULL
will also be returned if the key is not found. hash
can be a valid precomputed hash value, or 0 to ask for it to be computed.
SV * hv_delete_ent(HV *hv, SV *keysv, I32 flags, U32 hash)
HvENAME
Returns the effective name of a stash, or NULL if there is none. The effective name represents a location in the symbol table where this stash resides. It is updated automatically when packages are aliased or deleted. A stash that is no longer in the symbol table has no effective name. This name is preferable to HvNAME
for use in MRO linearisations and isa caches.
char* HvENAME(HV* stash)
HvENAMELEN
Returns the length of the stash's effective name.
STRLEN HvENAMELEN(HV *stash)
HvENAMEUTF8
Returns true if the effective name is in UTF-8 encoding.
unsigned char HvENAMEUTF8(HV *stash)
hv_exists
hv_existss
These return a boolean indicating whether the specified hash key exists.
In hv_existss
, the key must be a C language string literal, enclosed in double quotes. It is never treated as being in UTF-8. There is no length_parameter.
In hv_exists
, the absolute value of klen
is the length of the key. If klen
is negative the key is assumed to be in UTF-8-encoded Unicode.
bool hv_exists (HV *hv, const char *key, I32 klen)
bool hv_existss(HV *hv, "key")
hv_exists_ent
Returns a boolean indicating whether the specified hash key exists. hash
can be a valid precomputed hash value, or 0 to ask for it to be computed.
bool hv_exists_ent(HV *hv, SV *keysv, U32 hash)
hv_fetch
hv_fetchs
These return the SV which corresponds to the specified key in the hash.
In hv_fetchs
, the key must be a C language string literal, enclosed in double quotes. It is never treated as being in UTF-8. There is no length_parameter.
In hv_fetch
, the absolute value of klen
is the length of the key. If klen
is negative the key is assumed to be in UTF-8-encoded Unicode.
In both, if lval
is set, then the fetch will be part of a store. This means that if there is no value in the hash associated with the given key, then one is created and a pointer to it is returned. The SV*
it points to can be assigned to. But always check that the return value is non-null before dereferencing it to an SV*
.
See "Understanding the Magic of Tied Hashes and Arrays" in perlguts for more information on how to use this function on tied hashes.
SV ** hv_fetch (HV *hv, const char *key, I32 klen, I32 lval)
SV ** hv_fetchs(HV *hv, "key", I32 lval)
hv_fetch_ent
Returns the hash entry which corresponds to the specified key in the hash. hash
must be a valid precomputed hash number for the given key
, or 0 if you want the function to compute it. IF lval
is set then the fetch will be part of a store. Make sure the return value is non-null before accessing it. The return value when hv
is a tied hash is a pointer to a static location, so be sure to make a copy of the structure if you need to store it somewhere.
See "Understanding the Magic of Tied Hashes and Arrays" in perlguts for more information on how to use this function on tied hashes.
HE * hv_fetch_ent(HV *hv, SV *keysv, I32 lval, U32 hash)
hv_fetchs
Like hv_fetch
, but takes a literal string instead of a string/length pair.
SV** hv_fetchs(HV* tb, "key", I32 lval)
HvFILL
Returns the number of hash buckets that happen to be in use.
As of perl 5.25 this function is used only for debugging purposes, and the number of used hash buckets is not in any way cached, thus this function can be costly to execute as it must iterate over all the buckets in the hash.
STRLEN HvFILL(HV *const hv)
HvHasAUX
Returns true if the HV has a struct xpvhv_aux
extension. Use this to check whether it is valid to call HvAUX()
.
bool HvHasAUX(HV *const hv)
hv_iterinit
Prepares a starting point to traverse a hash table. Returns the number of keys in the hash, including placeholders (i.e. the same as HvTOTALKEYS(hv)
). The return value is currently only meaningful for hashes without tie magic.
NOTE: Before version 5.004_65, hv_iterinit
used to return the number of hash buckets that happen to be in use. If you still need that esoteric value, you can get it through the macro HvFILL(hv)
.
I32 hv_iterinit(HV *hv)
hv_iterkey
Returns the key from the current position of the hash iterator. See "hv_iterinit"
.
char * hv_iterkey(HE *entry, I32 *retlen)
hv_iterkeysv
Returns the key as an SV*
from the current position of the hash iterator. The return value will always be a mortal copy of the key. Also see "hv_iterinit"
.
SV * hv_iterkeysv(HE *entry)
hv_iternext
Returns entries from a hash iterator. See "hv_iterinit"
.
You may call hv_delete
or hv_delete_ent
on the hash entry that the iterator currently points to, without losing your place or invalidating your iterator. Note that in this case the current entry is deleted from the hash with your iterator holding the last reference to it. Your iterator is flagged to free the entry on the next call to hv_iternext
, so you must not discard your iterator immediately else the entry will leak - call hv_iternext
to trigger the resource deallocation.
HE * hv_iternext(HV *hv)
hv_iternext_flags
NOTE: hv_iternext_flags
is experimental and may change or be removed without notice.
Returns entries from a hash iterator. See "hv_iterinit"
and "hv_iternext"
. The flags
value will normally be zero; if HV_ITERNEXT_WANTPLACEHOLDERS
is set the placeholders keys (for restricted hashes) will be returned in addition to normal keys. By default placeholders are automatically skipped over. Currently a placeholder is implemented with a value that is &PL_sv_placeholder
. Note that the implementation of placeholders and restricted hashes may change, and the implementation currently is insufficiently abstracted for any change to be tidy.
HE * hv_iternext_flags(HV *hv, I32 flags)
hv_iternextsv
Performs an hv_iternext
, hv_iterkey
, and hv_iterval
in one operation.
SV * hv_iternextsv(HV *hv, char **key, I32 *retlen)
hv_iterval
Returns the value from the current position of the hash iterator. See "hv_iterkey"
.
SV * hv_iterval(HV *hv, HE *entry)
hv_ksplit
Attempt to grow the hash hv
so it has at least newmax
buckets available. Perl chooses the actual number for its convenience.
This is the same as doing the following in Perl code:
keys %hv = newmax;
void hv_ksplit(HV *hv, IV newmax)
hv_magic
Adds magic to a hash. See "sv_magic"
.
void hv_magic(HV *hv, GV *gv, int how)
HvNAME
Returns the package name of a stash, or NULL
if stash
isn't a stash. See "SvSTASH"
, "CvSTASH"
.
char* HvNAME(HV* stash)
HvNAMELEN
Returns the length of the stash's name.
Disfavored forms of HvNAME and HvNAMELEN; suppress mention of them
STRLEN HvNAMELEN(HV *stash)
hv_name_set
hv_name_sets
These each set the name of stash hv
to the specified name.
They differ only in how the name is specified.
In hv_name_sets
, the name is a literal C string, enclosed in double quotes.
In hv_name_set
, name
points to the first byte of the name, and an additional parameter, len
, specifies its length in bytes. Hence, the name may contain embedded-NUL characters.
If SVf_UTF8
is set in flags
, the name is treated as being in UTF-8; otherwise not.
If HV_NAME_SETALL
is set in flags
, both the name and the effective name are set.
void hv_name_set (HV *hv, const char *name, U32 len, U32 flags)
void hv_name_sets(HV *hv, "name", U32 flags)
HvNAMEUTF8
Returns true if the name is in UTF-8 encoding.
unsigned char HvNAMEUTF8(HV *stash)
hv_scalar
Evaluates the hash in scalar context and returns the result.
When the hash is tied dispatches through to the SCALAR method, otherwise returns a mortal SV containing the number of keys in the hash.
Note, prior to 5.25 this function returned what is now returned by the hv_bucket_ratio() function.
SV * hv_scalar(HV *hv)
hv_store
hv_stores
These each store SV val
with the specified key in hash hv
, returning NULL if the operation failed or if the value did not need to be actually stored within the hash (as in the case of tied hashes). Otherwise it can be dereferenced to get the original SV*
.
They differ only in how the hash key is specified.
In hv_stores
, the key must be a C language string literal, enclosed in double quotes. It is never treated as being in UTF-8. There is no length_parameter.
In hv_store
, key
is either NULL or points to the first byte of the string specifying the key, and its length in bytes is given by the absolute value of an additional parameter, klen
. A NULL key indicates the key is to be treated as undef
, and klen
is ignored; otherwise the key string may contain embedded-NUL bytes. If klen
is negative, the string is treated as being encoded in UTF-8; otherwise not.
hv_store
has another extra parameter, hash
, a precomputed hash of the key string, or zero if it has not been precomputed. This parameter is omitted from hv_stores
, as it is computed automatically at compile time.
If <hv> is NULL, NULL is returned and no action is taken.
If val
is NULL, it is treated as being undef
; otherwise the caller is responsible for suitably incrementing the reference count of val
before the call, and decrementing it if the function returned NULL
. Effectively a successful hv_store
takes ownership of one reference to val
. This is usually what you want; a newly created SV has a reference count of one, so if all your code does is create SVs then store them in a hash, hv_store
will own the only reference to the new SV, and your code doesn't need to do anything further to tidy up.
hv_store
is not implemented as a call to "hv_store_ent
", and does not create a temporary SV for the key, so if your key data is not already in SV form then use hv_store
in preference to hv_store_ent
.
See "Understanding the Magic of Tied Hashes and Arrays" in perlguts for more information on how to use this function on tied hashes.
SV ** hv_store (HV *hv, const char *key, I32 klen, SV *val,
U32 hash)
SV ** hv_stores(HV *hv, "key", SV *val)
hv_store_ent
Stores val
in a hash. The hash key is specified as key
. The hash
parameter is the precomputed hash value; if it is zero then Perl will compute it. The return value is the new hash entry so created. It will be NULL
if the operation failed or if the value did not need to be actually stored within the hash (as in the case of tied hashes). Otherwise the contents of the return value can be accessed using the He?
macros described here. Note that the caller is responsible for suitably incrementing the reference count of val
before the call, and decrementing it if the function returned NULL. Effectively a successful hv_store_ent
takes ownership of one reference to val
. This is usually what you want; a newly created SV has a reference count of one, so if all your code does is create SVs then store them in a hash, hv_store
will own the only reference to the new SV, and your code doesn't need to do anything further to tidy up. Note that hv_store_ent
only reads the key
; unlike val
it does not take ownership of it, so maintaining the correct reference count on key
is entirely the caller's responsibility. The reason it does not take ownership, is that key
is not used after this function returns, and so can be freed immediately. hv_store
is not implemented as a call to hv_store_ent
, and does not create a temporary SV for the key, so if your key data is not already in SV form then use hv_store
in preference to hv_store_ent
.
See "Understanding the Magic of Tied Hashes and Arrays" in perlguts for more information on how to use this function on tied hashes.
HE * hv_store_ent(HV *hv, SV *key, SV *val, U32 hash)
hv_undef
Undefines the hash. The XS equivalent of undef(%hash)
.
As well as freeing all the elements of the hash (like hv_clear()
), this also frees any auxiliary data and storage associated with the hash.
See "av_clear" for a note about the hash possibly being invalid on return.
void hv_undef(HV *hv)
newHV
Creates a new HV. The reference count is set to 1.
HV * newHV()
newHVhv
The content of ohv
is copied to a new hash. A pointer to the new hash is returned.
HV * newHVhv(HV *hv)
Nullhv
DEPRECATED!
It is planned to remove Nullhv
from a future release of Perl. Do not use it for new code; remove it from existing code.
Null HV pointer.
(deprecated - use (HV *)NULL
instead)
PL_modglobal
PL_modglobal
is a general purpose, interpreter global HV for use by extensions that need to keep information on a per-interpreter basis. In a pinch, it can also be used as a symbol table for extensions to share data among each other. It is a good idea to use keys prefixed by the package name of the extension that owns the data.
On threaded perls, each thread has an independent copy of this variable; each initialized at creation time with the current value of the creating thread's copy.
HV* PL_modglobal
do_close
Close an I/O stream. This implements Perl "close
" in perlfunc.
gv
is the glob associated with the stream.
is_explict
is true
if this is an explicit close of the stream; false
if it is part of another operation, such as closing a pipe (which involves implicitly closing both ends).
Returns true
if successful; otherwise returns false
and sets errno
to indicate the cause.
bool do_close(GV *gv, bool is_explicit)
my_chsize
The C library chsize(3) if available, or a Perl implementation of it.
I32 my_chsize(int fd, Off_t length)
my_dirfd
The C library dirfd(3)
if available, or a Perl implementation of it, or die if not easily emulatable.
int my_dirfd(DIR *dir)
my_pclose
A wrapper for the C library pclose(3). Don't use the latter, as the Perl version knows things that interact with the rest of the perl interpreter.
I32 my_pclose(PerlIO *ptr)
my_popen
A wrapper for the C library popen(3). Don't use the latter, as the Perl version knows things that interact with the rest of the perl interpreter.
PerlIO * my_popen(const char *cmd, const char *mode)
newIO
Create a new IO, setting the reference count to 1.
IO * newIO()
PERL_FLUSHALL_FOR_CHILD
This defines a way to flush all output buffers. This may be a performance issue, so we allow people to disable it. Also, if we are using stdio, there are broken implementations of fflush(NULL) out there, Solaris being the most prominent.
void PERL_FLUSHALL_FOR_CHILD
PerlIO_apply_layers
PerlIO_binmode
PerlIO_canset_cnt
PerlIO_clearerr
PerlIO_close
PerlIO_debug
PerlIO_eof
PerlIO_error
PerlIO_exportFILE
PerlIO_fast_gets
PerlIO_fdopen
PerlIO_fileno
PerlIO_fill
PerlIO_findFILE
PerlIO_flush
PerlIO_get_base
PerlIO_get_bufsiz
PerlIO_get_cnt
PerlIO_get_ptr
PerlIO_getc
PerlIO_getpos
PerlIO_has_base
PerlIO_has_cntptr
PerlIO_importFILE
PerlIO_open
PerlIO_printf
PerlIO_putc
PerlIO_puts
PerlIO_read
PerlIO_releaseFILE
PerlIO_reopen
PerlIO_rewind
PerlIO_seek
PerlIO_set_cnt
PerlIO_set_ptrcnt
PerlIO_setlinebuf
PerlIO_setpos
PerlIO_stderr
PerlIO_stdin
PerlIO_stdout
PerlIO_stdoutf
PerlIO_tell
PerlIO_ungetc
PerlIO_unread
PerlIO_vprintf
PerlIO_write
Described in perlapio.
int PerlIO_apply_layers(PerlIO *f, const char *mode,
const char *layers)
int PerlIO_binmode (PerlIO *f, int ptype, int imode,
const char *layers)
int PerlIO_canset_cnt (PerlIO *f)
void PerlIO_clearerr (PerlIO *f)
int PerlIO_close (PerlIO *f)
void PerlIO_debug (const char *fmt, ...)
int PerlIO_eof (PerlIO *f)
int PerlIO_error (PerlIO *f)
FILE * PerlIO_exportFILE (PerlIO *f, const char *mode)
int PerlIO_fast_gets (PerlIO *f)
PerlIO * PerlIO_fdopen (int fd, const char *mode)
int PerlIO_fileno (PerlIO *f)
int PerlIO_fill (PerlIO *f)
FILE * PerlIO_findFILE (PerlIO *f)
int PerlIO_flush (PerlIO *f)
STDCHAR * PerlIO_get_base (PerlIO *f)
SSize_t PerlIO_get_bufsiz (PerlIO *f)
SSize_t PerlIO_get_cnt (PerlIO *f)
STDCHAR * PerlIO_get_ptr (PerlIO *f)
int PerlIO_getc (PerlIO *d)
int PerlIO_getpos (PerlIO *f, SV *save)
int PerlIO_has_base (PerlIO *f)
int PerlIO_has_cntptr (PerlIO *f)
PerlIO * PerlIO_importFILE (FILE *stdio, const char *mode)
PerlIO * PerlIO_open (const char *path, const char *mode)
int PerlIO_printf (PerlIO *f, const char *fmt, ...)
int PerlIO_putc (PerlIO *f, int ch)
int PerlIO_puts (PerlIO *f, const char *string)
SSize_t PerlIO_read (PerlIO *f, void *vbuf,
Size_t count)
void PerlIO_releaseFILE (PerlIO *f, FILE *stdio)
PerlIO * PerlIO_reopen (const char *path, const char *mode,
PerlIO *old)
void PerlIO_rewind (PerlIO *f)
int PerlIO_seek (PerlIO *f, Off_t offset,
int whence)
void PerlIO_set_cnt (PerlIO *f, SSize_t cnt)
void PerlIO_set_ptrcnt (PerlIO *f, STDCHAR *ptr,
SSize_t cnt)
void PerlIO_setlinebuf (PerlIO *f)
int PerlIO_setpos (PerlIO *f, SV *saved)
PerlIO * PerlIO_stderr (PerlIO *f, const char *mode,
const char *layers)
PerlIO * PerlIO_stdin (PerlIO *f, const char *mode,
const char *layers)
PerlIO * PerlIO_stdout (PerlIO *f, const char *mode,
const char *layers)
int PerlIO_stdoutf (const char *fmt, ...)
Off_t PerlIO_tell (PerlIO *f)
int PerlIO_ungetc (PerlIO *f, int ch)
SSize_t PerlIO_unread (PerlIO *f, const void *vbuf,
Size_t count)
int PerlIO_vprintf (PerlIO *f, const char *fmt,
va_list args)
SSize_t PerlIO_write (PerlIO *f, const void *vbuf,
Size_t count)
PERLIO_F_APPEND
PERLIO_F_CANREAD
PERLIO_F_CANWRITE
PERLIO_F_CRLF
PERLIO_F_EOF
PERLIO_F_ERROR
PERLIO_F_FASTGETS
PERLIO_F_LINEBUF
PERLIO_F_OPEN
PERLIO_F_RDBUF
PERLIO_F_TEMP
PERLIO_F_TRUNCATE
PERLIO_F_UNBUF
PERLIO_F_UTF8
PERLIO_F_WRBUF
Described in perliol.
PERLIO_FUNCS_CAST
Cast the pointer func
to be of type PerlIO_funcs *
.
PERLIO_FUNCS_DECL
Declare ftab
to be a PerlIO function table, that is, of type PerlIO_funcs
.
PERLIO_FUNCS_DECL(PerlIO * ftab)
PERLIO_K_BUFFERED
PERLIO_K_CANCRLF
PERLIO_K_FASTGETS
PERLIO_K_MULTIARG
PERLIO_K_RAW
Described in perliol.
repeatcpy
Make count
copies of the len
bytes beginning at from
, placing them into memory beginning at to
, which must be big enough to accommodate them all.
void repeatcpy(char *to, const char *from, SSize_t len, IV count)
CASTI32
This symbol is defined if the C compiler can cast negative or large floating point numbers to 32-bit ints.
HAS_INT64_T
This symbol will defined if the C compiler supports int64_t
. Usually the inttypes.h needs to be included, but sometimes sys/types.h is enough.
HAS_LONG_LONG
This symbol will be defined if the C compiler supports long long.
HAS_QUAD
This symbol, if defined, tells that there's a 64-bit integer type, Quad_t
, and its unsigned counterpart, Uquad_t
. QUADKIND
will be one of QUAD_IS_INT
, QUAD_IS_LONG
, QUAD_IS_LONG_LONG
, QUAD_IS_INT64_T
, or QUAD_IS___INT64
.
I32df
This symbol defines the format string used for printing a Perl I32 as a signed decimal integer.
INT16_C
INT32_C
INT64_C
Returns a token the C compiler recognizes for the constant number
of the corresponding integer type on the machine.
If the machine does not have a 64-bit type, INT64_C
is undefined. Use "INTMAX_C"
to get the largest type available on the platform.
I16 INT16_C(number)
I32 INT32_C(number)
I64 INT64_C(number)
INTMAX_C
Returns a token the C compiler recognizes for the constant number
of the widest integer type on the machine. For example, if the machine has long long
s, INTMAX_C(-1)
would yield
-1LL
See also, for example, "INT32_C"
.
Use "IV" to declare variables of the maximum usable size on this platform.
INTMAX_C(number)
INTSIZE
This symbol contains the value of sizeof(int)
so that the C preprocessor can make decisions based on it.
I8SIZE
This symbol contains the sizeof(I8)
.
I16SIZE
This symbol contains the sizeof(I16)
.
I32SIZE
This symbol contains the sizeof(I32)
.
I64SIZE
This symbol contains the sizeof(I64)
.
I8TYPE
This symbol defines the C type used for Perl's I8.
I16TYPE
This symbol defines the C type used for Perl's I16.
I32TYPE
This symbol defines the C type used for Perl's I32.
I64TYPE
This symbol defines the C type used for Perl's I64.
IV_MAX
The largest signed integer that fits in an IV on this platform.
IV IV_MAX
IV_MIN
The negative signed integer furthest away from 0 that fits in an IV on this platform.
IV IV_MIN
IVSIZE
This symbol contains the sizeof(IV)
.
IVTYPE
This symbol defines the C type used for Perl's IV.
line_t
The typedef to use to declare variables that are to hold line numbers.
LONGLONGSIZE
This symbol contains the size of a long long, so that the C preprocessor can make decisions based on it. It is only defined if the system supports long long.
LONGSIZE
This symbol contains the value of sizeof(long)
so that the C preprocessor can make decisions based on it.
memzero
Set the l
bytes starting at *d
to all zeroes.
void memzero(void * d, Size_t l)
PERL_INT_FAST8_T
PERL_INT_FAST16_T
PERL_UINT_FAST8_T
PERL_UINT_FAST16_T
These are equivalent to the correspondingly-named C99 typedefs on platforms that have those; they evaluate to int
and unsigned int
on platforms that don't, so that you can portably take advantage of this C99 feature.
PERL_INT_MAX
PERL_INT_MIN
PERL_LONG_MAX
PERL_LONG_MIN
PERL_QUAD_MAX
PERL_QUAD_MIN
PERL_SHORT_MAX
PERL_SHORT_MIN
PERL_UCHAR_MAX
PERL_UCHAR_MIN
PERL_UINT_MAX
PERL_UINT_MIN
PERL_ULONG_MAX
PERL_ULONG_MIN
PERL_UQUAD_MAX
PERL_UQUAD_MIN
PERL_USHORT_MAX
PERL_USHORT_MIN
These give the largest and smallest number representable in the current platform in variables of the corresponding types.
For signed types, the smallest representable number is the most negative number, the one furthest away from zero.
For C99 and later compilers, these correspond to things like INT_MAX
, which are available to the C code. But these constants, furnished by Perl, allow code compiled on earlier compilers to portably have access to the same constants.
int PERL_INT_MAX
int PERL_INT_MIN
long PERL_LONG_MAX
long PERL_LONG_MIN
IV PERL_QUAD_MAX
IV PERL_QUAD_MIN
short PERL_SHORT_MAX
short PERL_SHORT_MIN
U8 PERL_UCHAR_MAX
U8 PERL_UCHAR_MIN
unsigned int PERL_UINT_MAX
unsigned int PERL_UINT_MIN
unsigned long PERL_ULONG_MAX
unsigned long PERL_ULONG_MIN
UV PERL_UQUAD_MAX
UV PERL_UQUAD_MIN
unsigned short PERL_USHORT_MAX
unsigned short PERL_USHORT_MIN
SHORTSIZE
This symbol contains the value of sizeof(short)
so that the C preprocessor can make decisions based on it.
UINT16_C
UINT32_C
UINT64_C
Returns a token the C compiler recognizes for the constant number
of the corresponding unsigned integer type on the machine.
If the machine does not have a 64-bit type, UINT64_C
is undefined. Use "UINTMAX_C"
to get the largest type available on the platform.
U16 UINT16_C(number)
U32 UINT32_C(number)
U64 UINT64_C(number)
UINTMAX_C
Returns a token the C compiler recognizes for the constant number
of the widest unsigned integer type on the machine. For example, if the machine has long
s, UINTMAX_C(1)
would yield
1UL
See also, for example, "UINT32_C"
.
Use "UV" to declare variables of the maximum usable size on this platform.
UINTMAX_C(number)
U32of
This symbol defines the format string used for printing a Perl U32 as an unsigned octal integer.
U8SIZE
This symbol contains the sizeof(U8)
.
U16SIZE
This symbol contains the sizeof(U16)
.
U32SIZE
This symbol contains the sizeof(U32)
.
U64SIZE
This symbol contains the sizeof(U64)
.
U8TYPE
This symbol defines the C type used for Perl's U8.
U16TYPE
This symbol defines the C type used for Perl's U16.
U32TYPE
This symbol defines the C type used for Perl's U32.
U64TYPE
This symbol defines the C type used for Perl's U64.
U32uf
This symbol defines the format string used for printing a Perl U32 as an unsigned decimal integer.
UV_MAX
The largest unsigned integer that fits in a UV on this platform.
UV UV_MAX
UV_MIN
The smallest unsigned integer that fits in a UV on this platform. It should equal zero.
UV UV_MIN
UVSIZE
This symbol contains the sizeof(UV)
.
UVTYPE
This symbol defines the C type used for Perl's UV.
U32Xf
This symbol defines the format string used for printing a Perl U32 as an unsigned hexadecimal integer in uppercase ABCDEF
.
U32xf
This symbol defines the format string used for printing a Perl U32 as an unsigned hexadecimal integer in lowercase abcdef.
WIDEST_UTYPE
Yields the widest unsigned integer type on the platform, currently either U32
or U64
. This can be used in declarations such as
WIDEST_UTYPE my_uv;
or casts
my_uv = (WIDEST_UTYPE) val;
These are used for formatting the corresponding type For example, instead of saying
Perl_newSVpvf(pTHX_ "Create an SV with a %d in it\n", iv);
use
Perl_newSVpvf(pTHX_ "Create an SV with a " IVdf " in it\n", iv);
This keeps you from having to know if, say an IV, needs to be printed as %d
, %ld
, or something else.
IVdf
This symbol defines the format string used for printing a Perl IV as a signed decimal integer.
NVef
This symbol defines the format string used for printing a Perl NV using %e-ish floating point format.
NVff
This symbol defines the format string used for printing a Perl NV using %f-ish floating point format.
NVgf
This symbol defines the format string used for printing a Perl NV using %g-ish floating point format.
PERL_PRIeldbl
This symbol, if defined, contains the string used by stdio to format long doubles (format 'e') for output.
PERL_PRIfldbl
This symbol, if defined, contains the string used by stdio to format long doubles (format 'f') for output.
PERL_PRIgldbl
This symbol, if defined, contains the string used by stdio to format long doubles (format 'g') for output.
PERL_SCNfldbl
This symbol, if defined, contains the string used by stdio to format long doubles (format 'f') for input.
PRINTF_FORMAT_NULL_OK
Allows __printf__
format to be null when checking printf-style
UVf
DEPRECATED!
It is planned to remove UVf
from a future release of Perl. Do not use it for new code; remove it from existing code.
Obsolete form of UVuf
, which you should convert to instead use
const char * UVf
UVof
This symbol defines the format string used for printing a Perl UV as an unsigned octal integer.
UVuf
This symbol defines the format string used for printing a Perl UV as an unsigned decimal integer.
UVXf
This symbol defines the format string used for printing a Perl UV as an unsigned hexadecimal integer in uppercase ABCDEF
.
UVxf
This symbol defines the format string used for printing a Perl UV as an unsigned hexadecimal integer in lowercase abcdef.
This is the lower layer of the Perl parser, managing characters and tokens.
lex_bufutf8
NOTE: lex_bufutf8
is experimental and may change or be removed without notice.
Indicates whether the octets in the lexer buffer ("PL_parser->linestr") should be interpreted as the UTF-8 encoding of Unicode characters. If not, they should be interpreted as Latin-1 characters. This is analogous to the SvUTF8
flag for scalars.
In UTF-8 mode, it is not guaranteed that the lexer buffer actually contains valid UTF-8. Lexing code must be robust in the face of invalid encoding.
The actual SvUTF8
flag of the "PL_parser->linestr" scalar is significant, but not the whole story regarding the input character encoding. Normally, when a file is being read, the scalar contains octets and its SvUTF8
flag is off, but the octets should be interpreted as UTF-8 if the use utf8
pragma is in effect. During a string eval, however, the scalar may have the SvUTF8
flag on, and in this case its octets should be interpreted as UTF-8 unless the use bytes
pragma is in effect. This logic may change in the future; use this function instead of implementing the logic yourself.
bool lex_bufutf8()
lex_discard_to
NOTE: lex_discard_to
is experimental and may change or be removed without notice.
Discards the first part of the "PL_parser->linestr" buffer, up to ptr
. The remaining content of the buffer will be moved, and all pointers into the buffer updated appropriately. ptr
must not be later in the buffer than the position of "PL_parser->bufptr": it is not permitted to discard text that has yet to be lexed.
Normally it is not necessarily to do this directly, because it suffices to use the implicit discarding behaviour of "lex_next_chunk" and things based on it. However, if a token stretches across multiple lines, and the lexing code has kept multiple lines of text in the buffer for that purpose, then after completion of the token it would be wise to explicitly discard the now-unneeded earlier lines, to avoid future multi-line tokens growing the buffer without bound.
void lex_discard_to(char *ptr)
lex_grow_linestr
NOTE: lex_grow_linestr
is experimental and may change or be removed without notice.
Reallocates the lexer buffer ("PL_parser->linestr") to accommodate at least len
octets (including terminating NUL
). Returns a pointer to the reallocated buffer. This is necessary before making any direct modification of the buffer that would increase its length. "lex_stuff_pvn" provides a more convenient way to insert text into the buffer.
Do not use SvGROW
or sv_grow
directly on PL_parser->linestr
; this function updates all of the lexer's variables that point directly into the buffer.
char * lex_grow_linestr(STRLEN len)
lex_next_chunk
NOTE: lex_next_chunk
is experimental and may change or be removed without notice.
Reads in the next chunk of text to be lexed, appending it to "PL_parser->linestr". This should be called when lexing code has looked to the end of the current chunk and wants to know more. It is usual, but not necessary, for lexing to have consumed the entirety of the current chunk at this time.
If "PL_parser->bufptr" is pointing to the very end of the current chunk (i.e., the current chunk has been entirely consumed), normally the current chunk will be discarded at the same time that the new chunk is read in. If flags
has the LEX_KEEP_PREVIOUS
bit set, the current chunk will not be discarded. If the current chunk has not been entirely consumed, then it will not be discarded regardless of the flag.
Returns true if some new text was added to the buffer, or false if the buffer has reached the end of the input text.
bool lex_next_chunk(U32 flags)
lex_peek_unichar
NOTE: lex_peek_unichar
is experimental and may change or be removed without notice.
Looks ahead one (Unicode) character in the text currently being lexed. Returns the codepoint (unsigned integer value) of the next character, or -1 if lexing has reached the end of the input text. To consume the peeked character, use "lex_read_unichar".
If the next character is in (or extends into) the next chunk of input text, the next chunk will be read in. Normally the current chunk will be discarded at the same time, but if flags
has the LEX_KEEP_PREVIOUS
bit set, then the current chunk will not be discarded.
If the input is being interpreted as UTF-8 and a UTF-8 encoding error is encountered, an exception is generated.
I32 lex_peek_unichar(U32 flags)
lex_read_space
NOTE: lex_read_space
is experimental and may change or be removed without notice.
Reads optional spaces, in Perl style, in the text currently being lexed. The spaces may include ordinary whitespace characters and Perl-style comments. #line
directives are processed if encountered. "PL_parser->bufptr" is moved past the spaces, so that it points at a non-space character (or the end of the input text).
If spaces extend into the next chunk of input text, the next chunk will be read in. Normally the current chunk will be discarded at the same time, but if flags
has the LEX_KEEP_PREVIOUS
bit set, then the current chunk will not be discarded.
void lex_read_space(U32 flags)
lex_read_to
NOTE: lex_read_to
is experimental and may change or be removed without notice.
Consume text in the lexer buffer, from "PL_parser->bufptr" up to ptr
. This advances "PL_parser->bufptr" to match ptr
, performing the correct bookkeeping whenever a newline character is passed. This is the normal way to consume lexed text.
Interpretation of the buffer's octets can be abstracted out by using the slightly higher-level functions "lex_peek_unichar" and "lex_read_unichar".
void lex_read_to(char *ptr)
lex_read_unichar
NOTE: lex_read_unichar
is experimental and may change or be removed without notice.
Reads the next (Unicode) character in the text currently being lexed. Returns the codepoint (unsigned integer value) of the character read, and moves "PL_parser->bufptr" past the character, or returns -1 if lexing has reached the end of the input text. To non-destructively examine the next character, use "lex_peek_unichar" instead.
If the next character is in (or extends into) the next chunk of input text, the next chunk will be read in. Normally the current chunk will be discarded at the same time, but if flags
has the LEX_KEEP_PREVIOUS
bit set, then the current chunk will not be discarded.
If the input is being interpreted as UTF-8 and a UTF-8 encoding error is encountered, an exception is generated.
I32 lex_read_unichar(U32 flags)
lex_start
NOTE: lex_start
is experimental and may change or be removed without notice.
Creates and initialises a new lexer/parser state object, supplying a context in which to lex and parse from a new source of Perl code. A pointer to the new state object is placed in "PL_parser". An entry is made on the save stack so that upon unwinding, the new state object will be destroyed and the former value of "PL_parser" will be restored. Nothing else need be done to clean up the parsing context.
The code to be parsed comes from line
and rsfp
. line
, if non-null, provides a string (in SV form) containing code to be parsed. A copy of the string is made, so subsequent modification of line
does not affect parsing. rsfp
, if non-null, provides an input stream from which code will be read to be parsed. If both are non-null, the code in line
comes first and must consist of complete lines of input, and rsfp
supplies the remainder of the source.
The flags
parameter is reserved for future use. Currently it is only used by perl internally, so extensions should always pass zero.
void lex_start(SV *line, PerlIO *rsfp, U32 flags)
lex_stuff_pv
NOTE: lex_stuff_pv
is experimental and may change or be removed without notice.
Insert characters into the lexer buffer ("PL_parser->linestr"), immediately after the current lexing point ("PL_parser->bufptr"), reallocating the buffer if necessary. This means that lexing code that runs later will see the characters as if they had appeared in the input. It is not recommended to do this as part of normal parsing, and most uses of this facility run the risk of the inserted characters being interpreted in an unintended manner.
The string to be inserted is represented by octets starting at pv
and continuing to the first nul. These octets are interpreted as either UTF-8 or Latin-1, according to whether the LEX_STUFF_UTF8
flag is set in flags
. The characters are recoded for the lexer buffer, according to how the buffer is currently being interpreted ("lex_bufutf8"). If it is not convenient to nul-terminate a string to be inserted, the "lex_stuff_pvn" function is more appropriate.
void lex_stuff_pv(const char *pv, U32 flags)
lex_stuff_pvn
NOTE: lex_stuff_pvn
is experimental and may change or be removed without notice.
Insert characters into the lexer buffer ("PL_parser->linestr"), immediately after the current lexing point ("PL_parser->bufptr"), reallocating the buffer if necessary. This means that lexing code that runs later will see the characters as if they had appeared in the input. It is not recommended to do this as part of normal parsing, and most uses of this facility run the risk of the inserted characters being interpreted in an unintended manner.
The string to be inserted is represented by len
octets starting at pv
. These octets are interpreted as either UTF-8 or Latin-1, according to whether the LEX_STUFF_UTF8
flag is set in flags
. The characters are recoded for the lexer buffer, according to how the buffer is currently being interpreted ("lex_bufutf8"). If a string to be inserted is available as a Perl scalar, the "lex_stuff_sv" function is more convenient.
void lex_stuff_pvn(const char *pv, STRLEN len, U32 flags)
lex_stuff_pvs
NOTE: lex_stuff_pvs
is experimental and may change or be removed without notice.
Like "lex_stuff_pvn", but takes a literal string instead of a string/length pair.
void lex_stuff_pvs("pv", U32 flags)
lex_stuff_sv
NOTE: lex_stuff_sv
is experimental and may change or be removed without notice.
Insert characters into the lexer buffer ("PL_parser->linestr"), immediately after the current lexing point ("PL_parser->bufptr"), reallocating the buffer if necessary. This means that lexing code that runs later will see the characters as if they had appeared in the input. It is not recommended to do this as part of normal parsing, and most uses of this facility run the risk of the inserted characters being interpreted in an unintended manner.
The string to be inserted is the string value of sv
. The characters are recoded for the lexer buffer, according to how the buffer is currently being interpreted ("lex_bufutf8"). If a string to be inserted is not already a Perl scalar, the "lex_stuff_pvn" function avoids the need to construct a scalar.
void lex_stuff_sv(SV *sv, U32 flags)
lex_unstuff
NOTE: lex_unstuff
is experimental and may change or be removed without notice.
Discards text about to be lexed, from "PL_parser->bufptr" up to ptr
. Text following ptr
will be moved, and the buffer shortened. This hides the discarded text from any lexing code that runs later, as if the text had never appeared.
This is not the normal way to consume lexed text. For that, use "lex_read_to".
void lex_unstuff(char *ptr)
parse_arithexpr
NOTE: parse_arithexpr
is experimental and may change or be removed without notice.
Parse a Perl arithmetic expression. This may contain operators of precedence down to the bit shift operators. The expression must be followed (and thus terminated) either by a comparison or lower-precedence operator or by something that would normally terminate an expression such as semicolon. If flags
has the PARSE_OPTIONAL
bit set, then the expression is optional, otherwise it is mandatory. It is up to the caller to ensure that the dynamic parser state ("PL_parser" et al) is correctly set to reflect the source of the code to be parsed and the lexical context for the expression.
The op tree representing the expression is returned. If an optional expression is absent, a null pointer is returned, otherwise the pointer will be non-null.
If an error occurs in parsing or compilation, in most cases a valid op tree is returned anyway. The error is reflected in the parser state, normally resulting in a single exception at the top level of parsing which covers all the compilation errors that occurred. Some compilation errors, however, will throw an exception immediately.
OP * parse_arithexpr(U32 flags)
parse_barestmt
NOTE: parse_barestmt
is experimental and may change or be removed without notice.
Parse a single unadorned Perl statement. This may be a normal imperative statement or a declaration that has compile-time effect. It does not include any label or other affixture. It is up to the caller to ensure that the dynamic parser state ("PL_parser" et al) is correctly set to reflect the source of the code to be parsed and the lexical context for the statement.
The op tree representing the statement is returned. This may be a null pointer if the statement is null, for example if it was actually a subroutine definition (which has compile-time side effects). If not null, it will be ops directly implementing the statement, suitable to pass to "newSTATEOP". It will not normally include a nextstate
or equivalent op (except for those embedded in a scope contained entirely within the statement).
If an error occurs in parsing or compilation, in most cases a valid op tree (most likely null) is returned anyway. The error is reflected in the parser state, normally resulting in a single exception at the top level of parsing which covers all the compilation errors that occurred. Some compilation errors, however, will throw an exception immediately.
The flags
parameter is reserved for future use, and must always be zero.
OP * parse_barestmt(U32 flags)
parse_block
NOTE: parse_block
is experimental and may change or be removed without notice.
Parse a single complete Perl code block. This consists of an opening brace, a sequence of statements, and a closing brace. The block constitutes a lexical scope, so my
variables and various compile-time effects can be contained within it. It is up to the caller to ensure that the dynamic parser state ("PL_parser" et al) is correctly set to reflect the source of the code to be parsed and the lexical context for the statement.
The op tree representing the code block is returned. This is always a real op, never a null pointer. It will normally be a lineseq
list, including nextstate
or equivalent ops. No ops to construct any kind of runtime scope are included by virtue of it being a block.
If an error occurs in parsing or compilation, in most cases a valid op tree (most likely null) is returned anyway. The error is reflected in the parser state, normally resulting in a single exception at the top level of parsing which covers all the compilation errors that occurred. Some compilation errors, however, will throw an exception immediately.
The flags
parameter is reserved for future use, and must always be zero.
OP * parse_block(U32 flags)
parse_fullexpr
NOTE: parse_fullexpr
is experimental and may change or be removed without notice.
Parse a single complete Perl expression. This allows the full expression grammar, including the lowest-precedence operators such as or
. The expression must be followed (and thus terminated) by a token that an expression would normally be terminated by: end-of-file, closing bracketing punctuation, semicolon, or one of the keywords that signals a postfix expression-statement modifier. If flags
has the PARSE_OPTIONAL
bit set, then the expression is optional, otherwise it is mandatory. It is up to the caller to ensure that the dynamic parser state ("PL_parser" et al) is correctly set to reflect the source of the code to be parsed and the lexical context for the expression.
The op tree representing the expression is returned. If an optional expression is absent, a null pointer is returned, otherwise the pointer will be non-null.
If an error occurs in parsing or compilation, in most cases a valid op tree is returned anyway. The error is reflected in the parser state, normally resulting in a single exception at the top level of parsing which covers all the compilation errors that occurred. Some compilation errors, however, will throw an exception immediately.
OP * parse_fullexpr(U32 flags)
parse_fullstmt
NOTE: parse_fullstmt
is experimental and may change or be removed without notice.
Parse a single complete Perl statement. This may be a normal imperative statement or a declaration that has compile-time effect, and may include optional labels. It is up to the caller to ensure that the dynamic parser state ("PL_parser" et al) is correctly set to reflect the source of the code to be parsed and the lexical context for the statement.
The op tree representing the statement is returned. This may be a null pointer if the statement is null, for example if it was actually a subroutine definition (which has compile-time side effects). If not null, it will be the result of a "newSTATEOP" call, normally including a nextstate
or equivalent op.
If an error occurs in parsing or compilation, in most cases a valid op tree (most likely null) is returned anyway. The error is reflected in the parser state, normally resulting in a single exception at the top level of parsing which covers all the compilation errors that occurred. Some compilation errors, however, will throw an exception immediately.
The flags
parameter is reserved for future use, and must always be zero.
OP * parse_fullstmt(U32 flags)
parse_label
NOTE: parse_label
is experimental and may change or be removed without notice.
Parse a single label, possibly optional, of the type that may prefix a Perl statement. It is up to the caller to ensure that the dynamic parser state ("PL_parser" et al) is correctly set to reflect the source of the code to be parsed. If flags
has the PARSE_OPTIONAL
bit set, then the label is optional, otherwise it is mandatory.
The name of the label is returned in the form of a fresh scalar. If an optional label is absent, a null pointer is returned.
If an error occurs in parsing, which can only occur if the label is mandatory, a valid label is returned anyway. The error is reflected in the parser state, normally resulting in a single exception at the top level of parsing which covers all the compilation errors that occurred.
SV * parse_label(U32 flags)
parse_listexpr
NOTE: parse_listexpr
is experimental and may change or be removed without notice.
Parse a Perl list expression. This may contain operators of precedence down to the comma operator. The expression must be followed (and thus terminated) either by a low-precedence logic operator such as or
or by something that would normally terminate an expression such as semicolon. If flags
has the PARSE_OPTIONAL
bit set, then the expression is optional, otherwise it is mandatory. It is up to the caller to ensure that the dynamic parser state ("PL_parser" et al) is correctly set to reflect the source of the code to be parsed and the lexical context for the expression.
The op tree representing the expression is returned. If an optional expression is absent, a null pointer is returned, otherwise the pointer will be non-null.
If an error occurs in parsing or compilation, in most cases a valid op tree is returned anyway. The error is reflected in the parser state, normally resulting in a single exception at the top level of parsing which covers all the compilation errors that occurred. Some compilation errors, however, will throw an exception immediately.
OP * parse_listexpr(U32 flags)
parse_stmtseq
NOTE: parse_stmtseq
is experimental and may change or be removed without notice.
Parse a sequence of zero or more Perl statements. These may be normal imperative statements, including optional labels, or declarations that have compile-time effect, or any mixture thereof. The statement sequence ends when a closing brace or end-of-file is encountered in a place where a new statement could have validly started. It is up to the caller to ensure that the dynamic parser state ("PL_parser" et al) is correctly set to reflect the source of the code to be parsed and the lexical context for the statements.
The op tree representing the statement sequence is returned. This may be a null pointer if the statements were all null, for example if there were no statements or if there were only subroutine definitions (which have compile-time side effects). If not null, it will be a lineseq
list, normally including nextstate
or equivalent ops.
If an error occurs in parsing or compilation, in most cases a valid op tree is returned anyway. The error is reflected in the parser state, normally resulting in a single exception at the top level of parsing which covers all the compilation errors that occurred. Some compilation errors, however, will throw an exception immediately.
The flags
parameter is reserved for future use, and must always be zero.
OP * parse_stmtseq(U32 flags)
parse_subsignature
NOTE: parse_subsignature
is experimental and may change or be removed without notice.
Parse a subroutine signature declaration. This is the contents of the parentheses following a named or anonymous subroutine declaration when the signatures
feature is enabled. Note that this function neither expects nor consumes the opening and closing parentheses around the signature; it is the caller's job to handle these.
This function must only be called during parsing of a subroutine; after "start_subparse" has been called. It might allocate lexical variables on the pad for the current subroutine.
The op tree to unpack the arguments from the stack at runtime is returned. This op tree should appear at the beginning of the compiled function. The caller may wish to use "op_append_list" to build their function body after it, or splice it together with the body before calling "newATTRSUB".
The flags
parameter is reserved for future use, and must always be zero.
OP * parse_subsignature(U32 flags)
parse_termexpr
NOTE: parse_termexpr
is experimental and may change or be removed without notice.
Parse a Perl term expression. This may contain operators of precedence down to the assignment operators. The expression must be followed (and thus terminated) either by a comma or lower-precedence operator or by something that would normally terminate an expression such as semicolon. If flags
has the PARSE_OPTIONAL
bit set, then the expression is optional, otherwise it is mandatory. It is up to the caller to ensure that the dynamic parser state ("PL_parser" et al) is correctly set to reflect the source of the code to be parsed and the lexical context for the expression.
The op tree representing the expression is returned. If an optional expression is absent, a null pointer is returned, otherwise the pointer will be non-null.
If an error occurs in parsing or compilation, in most cases a valid op tree is returned anyway. The error is reflected in the parser state, normally resulting in a single exception at the top level of parsing which covers all the compilation errors that occurred. Some compilation errors, however, will throw an exception immediately.
OP * parse_termexpr(U32 flags)
PL_parser
Pointer to a structure encapsulating the state of the parsing operation currently in progress. The pointer can be locally changed to perform a nested parse without interfering with the state of an outer parse. Individual members of PL_parser
have their own documentation.
PL_parser->bufend
NOTE: PL_parser->bufend
is experimental and may change or be removed without notice.
Direct pointer to the end of the chunk of text currently being lexed, the end of the lexer buffer. This is equal to SvPVX(PL_parser->linestr) + SvCUR(PL_parser->linestr)
. A NUL
character (zero octet) is always located at the end of the buffer, and does not count as part of the buffer's contents.
PL_parser->bufptr
NOTE: PL_parser->bufptr
is experimental and may change or be removed without notice.
Points to the current position of lexing inside the lexer buffer. Characters around this point may be freely examined, within the range delimited by SvPVX("PL_parser->linestr")
and "PL_parser->bufend". The octets of the buffer may be intended to be interpreted as either UTF-8 or Latin-1, as indicated by "lex_bufutf8".
Lexing code (whether in the Perl core or not) moves this pointer past the characters that it consumes. It is also expected to perform some bookkeeping whenever a newline character is consumed. This movement can be more conveniently performed by the function "lex_read_to", which handles newlines appropriately.
Interpretation of the buffer's octets can be abstracted out by using the slightly higher-level functions "lex_peek_unichar" and "lex_read_unichar".
PL_parser->linestart
NOTE: PL_parser->linestart
is experimental and may change or be removed without notice.
Points to the start of the current line inside the lexer buffer. This is useful for indicating at which column an error occurred, and not much else. This must be updated by any lexing code that consumes a newline; the function "lex_read_to" handles this detail.
PL_parser->linestr
NOTE: PL_parser->linestr
is experimental and may change or be removed without notice.
Buffer scalar containing the chunk currently under consideration of the text currently being lexed. This is always a plain string scalar (for which SvPOK
is true). It is not intended to be used as a scalar by normal scalar means; instead refer to the buffer directly by the pointer variables described below.
The lexer maintains various char*
pointers to things in the PL_parser->linestr
buffer. If PL_parser->linestr
is ever reallocated, all of these pointers must be updated. Don't attempt to do this manually, but rather use "lex_grow_linestr" if you need to reallocate the buffer.
The content of the text chunk in the buffer is commonly exactly one complete line of input, up to and including a newline terminator, but there are situations where it is otherwise. The octets of the buffer may be intended to be interpreted as either UTF-8 or Latin-1. The function "lex_bufutf8" tells you which. Do not use the SvUTF8
flag on this scalar, which may disagree with it.
For direct examination of the buffer, the variable "PL_parser->bufend" points to the end of the buffer. The current lexing position is pointed to by "PL_parser->bufptr". Direct use of these pointers is usually preferable to examination of the scalar through normal scalar means.
suspend_compcv
Implements part of the concept of a "suspended compilation CV", which can be used to pause the parser and compiler during parsing a CV in order to come back to it later on.
This function saves the current state of the subroutine under compilation (PL_compcv
) into the supplied buffer. This should be used initially to create the state in the buffer, as the final thing before a LEAVE
within a block.
ENTER;
start_subparse(0);
...
suspend_compcv(&buffer);
LEAVE;
Once suspended, the resume_compcv_final
or resume_compcv_and_save
function can later be used to continue the parsing from the point this stopped.
void suspend_compcv(struct suspended_compcv *buffer)
wrap_infix_plugin
NOTE: wrap_infix_plugin
is experimental and may change or be removed without notice.
NOTE: This API exists entirely for the purpose of making the CPAN module XS::Parse::Infix
work. It is not expected that additional modules will make use of it; rather, that they should use XS::Parse::Infix
to provide parsing of new infix operators.
Puts a C function into the chain of infix plugins. This is the preferred way to manipulate the "PL_infix_plugin" variable. new_plugin
is a pointer to the C function that is to be added to the infix plugin chain, and old_plugin_p
points to a storage location where a pointer to the next function in the chain will be stored. The value of new_plugin
is written into the "PL_infix_plugin" variable, while the value previously stored there is written to *old_plugin_p
.
Direct access to "PL_infix_plugin" should be avoided.
void wrap_infix_plugin(Perl_infix_plugin_t new_plugin,
Perl_infix_plugin_t *old_plugin_p)
wrap_keyword_plugin
NOTE: wrap_keyword_plugin
is experimental and may change or be removed without notice.
Puts a C function into the chain of keyword plugins. This is the preferred way to manipulate the "PL_keyword_plugin" variable. new_plugin
is a pointer to the C function that is to be added to the keyword plugin chain, and old_plugin_p
points to the storage location where a pointer to the next function in the chain will be stored. The value of new_plugin
is written into the "PL_keyword_plugin" variable, while the value previously stored there is written to *old_plugin_p
.
"PL_keyword_plugin" is global to an entire process, and a module wishing to hook keyword parsing may find itself invoked more than once per process, typically in different threads. To handle that situation, this function is idempotent. The location *old_plugin_p
must initially (once per process) contain a null pointer. A C variable of static duration (declared at file scope, typically also marked static
to give it internal linkage) will be implicitly initialised appropriately, if it does not have an explicit initialiser. This function will only actually modify the plugin chain if it finds *old_plugin_p
to be null. This function is also thread safe on the small scale. It uses appropriate locking to avoid race conditions in accessing "PL_keyword_plugin".
When this function is called, the function referenced by new_plugin
must be ready to be called, except for *old_plugin_p
being unfilled. In a threading situation, new_plugin
may be called immediately, even before this function has returned. *old_plugin_p
will always be appropriately set before new_plugin
is called. If new_plugin
decides not to do anything special with the identifier that it is given (which is the usual case for most calls to a keyword plugin), it must chain the plugin function referenced by *old_plugin_p
.
Taken all together, XS code to install a keyword plugin should typically look something like this:
static Perl_keyword_plugin_t next_keyword_plugin;
static OP *my_keyword_plugin(pTHX_
char *keyword_ptr, STRLEN keyword_len, OP **op_ptr)
{
if (memEQs(keyword_ptr, keyword_len,
"my_new_keyword")) {
...
} else {
return next_keyword_plugin(aTHX_
keyword_ptr, keyword_len, op_ptr);
}
}
BOOT:
wrap_keyword_plugin(my_keyword_plugin,
&next_keyword_plugin);
Direct access to "PL_keyword_plugin" should be avoided.
void wrap_keyword_plugin(Perl_keyword_plugin_t new_plugin,
Perl_keyword_plugin_t *old_plugin_p)
DECLARATION_FOR_LC_NUMERIC_MANIPULATION
This macro should be used as a statement. It declares a private variable (whose name begins with an underscore) that is needed by the other macros in this section. Failing to include this correctly should lead to a syntax error. For compatibility with C89 C compilers it should be placed in a block before any executable statements.
void DECLARATION_FOR_LC_NUMERIC_MANIPULATION
foldEQ_locale
Returns true if the leading len
bytes of the strings s1
and s2
are the same case-insensitively in the current locale; false otherwise.
I32 foldEQ_locale(const char *a, const char *b, I32 len)
HAS_DUPLOCALE
This symbol, if defined, indicates that the duplocale
routine is available to duplicate a locale object.
HAS_FREELOCALE
This symbol, if defined, indicates that the freelocale
routine is available to deallocates the resources associated with a locale object.
HAS_LC_MONETARY_2008
This symbol, if defined, indicates that the localeconv routine is available and has the additional members added in POSIX
1003.1-2008.
HAS_LOCALECONV
This symbol, if defined, indicates that the localeconv
routine is available for numeric and monetary formatting conventions.
HAS_LOCALECONV_L
This symbol, if defined, indicates that the localeconv_l
routine is available to query certain information about a locale.
HAS_NEWLOCALE
This symbol, if defined, indicates that the newlocale
routine is available to return a new locale object or modify an existing locale object.
HAS_NL_LANGINFO
This symbol, if defined, indicates that the nl_langinfo
routine is available to return locale data. You will also need langinfo.h and therefore I_LANGINFO
.
HAS_NL_LANGINFO_L
This symbol, if defined, indicates that the nl_langinfo_l
routine is available to return locale data. You will also need langinfo.h and therefore I_LANGINFO
.
HAS_QUERYLOCALE
This symbol, if defined, indicates that the querylocale
routine is available to return the name of the locale for a category mask.
HAS_SETLOCALE
This symbol, if defined, indicates that the setlocale
routine is available to handle locale-specific ctype implementations.
HAS_SETLOCALE_R
This symbol, if defined, indicates that the setlocale_r
routine is available to setlocale re-entrantly.
HAS_USELOCALE
This symbol, if defined, indicates that the uselocale
routine is available to set the current locale for the calling thread.
I_LANGINFO
This symbol, if defined, indicates that langinfo.h exists and should be included.
#ifdef I_LANGINFO
#include <langinfo.h>
#endif
I_LOCALE
This symbol, if defined, indicates to the C program that it should include locale.h.
#ifdef I_LOCALE
#include <locale.h>
#endif
IN_LOCALE
Evaluates to TRUE if the plain locale pragma without a parameter (use locale
) is in effect.
bool IN_LOCALE
IN_LOCALE_COMPILETIME
Evaluates to TRUE if, when compiling a perl program (including an eval
) if the plain locale pragma without a parameter (use locale
) is in effect.
bool IN_LOCALE_COMPILETIME
IN_LOCALE_RUNTIME
Evaluates to TRUE if, when executing a perl program (including an eval
) if the plain locale pragma without a parameter (use locale
) is in effect.
bool IN_LOCALE_RUNTIME
I_XLOCALE
This symbol, if defined, indicates to the C program that the header xlocale.h is available. See also "NEED_XLOCALE_H"
#ifdef I_XLOCALE
#include <xlocale.h>
#endif
NEED_XLOCALE_H
This symbol, if defined, indicates that the C program should include xlocale.h to get newlocale()
and its friends.
Perl_langinfo
Perl_langinfo8
Perl_langinfo
is an (almost) drop-in replacement for the system nl_langinfo(3)
, taking the same item
parameter values, and returning the same information. But it is more thread-safe than regular nl_langinfo()
, and hides the quirks of Perl's locale handling from your code, and can be used on systems that lack a native nl_langinfo
.
However, you should instead use either the improved version of this, "Perl_langinfo8", or even better, "sv_langinfo". The latter returns an SV, handling all the possible non-standard returns of nl_langinfo()
, including the UTF8ness of any returned string.
Perl_langinfo8
is identical to Perl_langinfo
except for an additional parameter, a pointer to a variable declared as "utf8ness_t
", into which it returns to you how you should treat the returned string with regards to it being encoded in UTF-8 or not.
These two functions share private per-thread memory that will be changed the next time either one of them is called with any input, but not before.
Concerning the differences between these and plain nl_langinfo()
:
Perl_langinfo8
has an extra parameter, described above. Besides this, the other reason they aren't quite a drop-in replacement is actually an advantage. The const
ness of the return allows the compiler to catch attempts to write into the returned buffer, which is illegal and could cause run-time crashes.
They deliver the correct results for the RADIXCHAR
and THOUSEP
items, without you having to write extra code. The reason for the extra code would be because these are from the LC_NUMERIC
locale category, which is normally kept set by Perl so that the radix is a dot, and the separator is the empty string, no matter what the underlying locale is supposed to be, and so to get the expected results, you have to temporarily toggle into the underlying locale, and later toggle back. (You could use plain nl_langinfo
and "STORE_LC_NUMERIC_FORCE_TO_UNDERLYING"
for this but then you wouldn't get the other advantages of Perl_langinfo()
; not keeping LC_NUMERIC
in the C (or equivalent) locale would break a lot of CPAN, which is expecting the radix (decimal point) character to be a dot.)
The system function they replace can have its static return buffer trashed, not only by a subsequent call to that function, but by a freelocale
, setlocale
, or other locale change. The returned buffer of these functions is not changed until the next call to one or the other, so the buffer is never in a trashed state.
The return buffer is per-thread, so it also is never overwritten by a call to these functions from another thread; unlike the function it replaces.
But most importantly, they work on systems that don't have nl_langinfo
, such as Windows, hence making your code more portable. Of the fifty-some possible items specified by the POSIX 2008 standard, https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/langinfo.h.html, only one is completely unimplemented, though on non-Windows platforms, another significant one is not fully implemented). They use various techniques to recover the other items, including calling localeconv(3)
, and strftime(3)
, both of which are specified in C89, so should be always be available. Later strftime()
versions have additional capabilities. If an item is not available on your system, this returns either the value associated with the C locale, or simply ""
, whichever is more appropriate.
It is important to note that, when called with an item that is recovered by using localeconv
, the buffer from any previous explicit call to localeconv(3)
will be overwritten. But you shouldn't be using localeconv
anyway because it is is very much not thread-safe, and suffers from the same problems outlined in item 'b.' above for the fields it returns that are controlled by the LC_NUMERIC locale category. Instead, avoid all of those problems by calling "Perl_localeconv", which is thread-safe; or by using the methods given in perlcall to call POSIX::localeconv()
, which is also thread-safe.
The details for those items which may deviate from what this emulation returns and what a native nl_langinfo()
would return are specified in I18N::Langinfo.
const char * Perl_langinfo (const nl_item item)
const char * Perl_langinfo8(const nl_item item,
utf8ness_t *utf8ness)
PERL_LC_ALL_CATEGORY_POSITIONS_INIT
This symbol, when defined, gives the C initializer for an array whose element [0] is the first category in the string returned by setlocale(LC_ALL, NULL)
when not all categories are the same, on systems that use a positional notation. After element [0] is LC_ALL_SEPARATOR
, then the category given by element [1] and so on.
PERL_LC_ALL_SEPARATOR
This symbol, if defined, gives the string returned by setlocale(LC_ALL, NULL)
to separate categories that are in different locales on systems that use a positional notation as opposed to 'name=value' pairs. An example on some platforms could be the '/' in "C/de_DE
/C/en_UK
/C/C"
PERL_LC_ALL_USES_NAME_VALUE_PAIRS
This symbol, if defined, indicates to the C program that the string returned by setlocale(LC_ALL, NULL)
uses 'name=value;' pairs to indicate what each category's locale is when they aren't all set to the same locale. For example, "LC_NUMERIC
=C;LC_CTYPE
=de_DE
;..." When not defined, the system uses positional notation.
Perl_localeconv
This is a thread-safe version of the libc localeconv(3). It is the same as POSIX::localeconv (returning a hash of the localeconv()
fields), but directly callable from XS code. The hash is mortalized, so must be dealt with immediately.
HV * Perl_localeconv(pTHX)
Perl_setlocale
This is an (almost) drop-in replacement for the system setlocale(3)
, taking the same parameters, and returning the same information, except that it returns the correct underlying LC_NUMERIC
locale. Regular setlocale
will instead return C
if the underlying locale has a non-dot decimal point character, or a non-empty thousands separator for displaying floating point numbers. This is because perl keeps that locale category such that it has a dot and empty separator, changing the locale briefly during the operations where the underlying one is required. Perl_setlocale
knows about this, and compensates; regular setlocale
doesn't.
Another reason it isn't completely a drop-in replacement is that it is declared to return const char *
, whereas the system setlocale omits the const
(presumably because its API was specified long ago, and can't be updated; it is illegal to change the information setlocale
returns; doing so leads to segfaults.)
Finally, Perl_setlocale
works under all circumstances, whereas plain setlocale
can be completely ineffective on some platforms under some configurations.
Changing the locale is not a good idea when more than one thread is running, except on systems where the predefined variable ${^SAFE_LOCALES}
is non-zero. This is because on such systems the locale is global to the whole process and not local to just the thread calling the function. So changing it in one thread instantaneously changes it in all. On some such systems, the system setlocale()
is ineffective, returning the wrong information, and failing to actually change the locale. z/OS refuses to try to change the locale once a second thread is created. Perl_setlocale
, should give you accurate results of what actually happened on these problematic platforms, returning NULL if the system forbade the locale change.
The return points to a per-thread static buffer, which is overwritten the next time Perl_setlocale
is called from the same thread.
const char * Perl_setlocale(const int category,
const char *locale)
RESTORE_LC_NUMERIC
This is used in conjunction with one of the macros "STORE_LC_NUMERIC_SET_TO_NEEDED" and "STORE_LC_NUMERIC_FORCE_TO_UNDERLYING" to properly restore the LC_NUMERIC
state.
A call to "DECLARATION_FOR_LC_NUMERIC_MANIPULATION" must have been made to declare at compile time a private variable used by this macro and the two STORE
ones. This macro should be called as a single statement, not an expression, but with an empty argument list, like this:
{
DECLARATION_FOR_LC_NUMERIC_MANIPULATION;
...
RESTORE_LC_NUMERIC();
...
}
void RESTORE_LC_NUMERIC()
SETLOCALE_ACCEPTS_ANY_LOCALE_NAME
This symbol, if defined, indicates that the setlocale routine is available and it accepts any input locale name as valid.
STORE_LC_NUMERIC_FORCE_TO_UNDERLYING
This is used by XS code that is LC_NUMERIC
locale-aware to force the locale for category LC_NUMERIC
to be what perl thinks is the current underlying locale. (The perl interpreter could be wrong about what the underlying locale actually is if some C or XS code has called the C library function setlocale(3) behind its back; calling "sync_locale" before calling this macro will update perl's records.)
A call to "DECLARATION_FOR_LC_NUMERIC_MANIPULATION" must have been made to declare at compile time a private variable used by this macro. This macro should be called as a single statement, not an expression, but with an empty argument list, like this:
{
DECLARATION_FOR_LC_NUMERIC_MANIPULATION;
...
STORE_LC_NUMERIC_FORCE_TO_UNDERLYING();
...
RESTORE_LC_NUMERIC();
...
}
The private variable is used to save the current locale state, so that the requisite matching call to "RESTORE_LC_NUMERIC" can restore it.
On threaded perls not operating with thread-safe functionality, this macro uses a mutex to force a critical section. Therefore the matching RESTORE should be close by, and guaranteed to be called.
void STORE_LC_NUMERIC_FORCE_TO_UNDERLYING()
STORE_LC_NUMERIC_SET_TO_NEEDED
This is used to help wrap XS or C code that is LC_NUMERIC
locale-aware. This locale category is generally kept set to a locale where the decimal radix character is a dot, and the separator between groups of digits is empty. This is because most XS code that reads floating point numbers is expecting them to have this syntax.
This macro makes sure the current LC_NUMERIC
state is set properly, to be aware of locale if the call to the XS or C code from the Perl program is from within the scope of a use locale
; or to ignore locale if the call is instead from outside such scope.
This macro is the start of wrapping the C or XS code; the wrap ending is done by calling the "RESTORE_LC_NUMERIC" macro after the operation. Otherwise the state can be changed that will adversely affect other XS code.
A call to "DECLARATION_FOR_LC_NUMERIC_MANIPULATION" must have been made to declare at compile time a private variable used by this macro. This macro should be called as a single statement, not an expression, but with an empty argument list, like this:
{
DECLARATION_FOR_LC_NUMERIC_MANIPULATION;
...
STORE_LC_NUMERIC_SET_TO_NEEDED();
...
RESTORE_LC_NUMERIC();
...
}
On threaded perls not operating with thread-safe functionality, this macro uses a mutex to force a critical section. Therefore the matching RESTORE should be close by, and guaranteed to be called; see "WITH_LC_NUMERIC_SET_TO_NEEDED" for a more contained way to ensure that.
void STORE_LC_NUMERIC_SET_TO_NEEDED()
STORE_LC_NUMERIC_SET_TO_NEEDED_IN
Same as "STORE_LC_NUMERIC_SET_TO_NEEDED" with in_lc_numeric provided as the precalculated value of IN_LC(LC_NUMERIC)
. It is the caller's responsibility to ensure that the status of PL_compiling
and PL_hints
cannot have changed since the precalculation.
void STORE_LC_NUMERIC_SET_TO_NEEDED_IN(bool in_lc_numeric)
sv_langinfo
This is the preferred interface for accessing the data that nl_langinfo(3) provides (or Perl's emulation of it on platforms lacking it), returning an SV. Unlike, the earlier-defined interfaces to this ("Perl_langinfo" and "Perl_langinfo8"), which return strings, the UTF8ness of the result is automatically handled for you. And like them, it is thread-safe and automatically handles getting the proper values for the RADIXCHAR
and THOUSEP
items (that calling the plain libc nl_langinfo()
could give the wrong results for). Like them, this also doesn't play well with the libc localeconv()
; use POSIX::localeconv()
instead.
There are a few deviations from what a native nl_langinfo()
would return and what this returns on platforms that don't implement that function. These are detailed in I18N::Langinfo.
SV * sv_langinfo(const nl_item item)
WITH_LC_NUMERIC_SET_TO_NEEDED
This macro invokes the supplied statement or block within the context of a "STORE_LC_NUMERIC_SET_TO_NEEDED" .. "RESTORE_LC_NUMERIC" pair if required, so eg:
WITH_LC_NUMERIC_SET_TO_NEEDED(
SNPRINTF_G(fv, ebuf, sizeof(ebuf), precis)
);
is equivalent to:
{
#ifdef USE_LOCALE_NUMERIC
DECLARATION_FOR_LC_NUMERIC_MANIPULATION;
STORE_LC_NUMERIC_SET_TO_NEEDED();
#endif
SNPRINTF_G(fv, ebuf, sizeof(ebuf), precis);
#ifdef USE_LOCALE_NUMERIC
RESTORE_LC_NUMERIC();
#endif
}
void WITH_LC_NUMERIC_SET_TO_NEEDED(block)
WITH_LC_NUMERIC_SET_TO_NEEDED_IN
Same as "WITH_LC_NUMERIC_SET_TO_NEEDED" with in_lc_numeric provided as the precalculated value of IN_LC(LC_NUMERIC)
. It is the caller's responsibility to ensure that the status of PL_compiling
and PL_hints
cannot have changed since the precalculation.
void WITH_LC_NUMERIC_SET_TO_NEEDED_IN(bool in_lc_numeric, block)
"Magic" is special data attached to SV structures in order to give them "magical" properties. When any Perl code tries to read from, or assign to, an SV marked as magical, it calls the 'get' or 'set' function associated with that SV's magic. A get is called prior to reading an SV, in order to give it a chance to update its internal value (get on $. writes the line number of the last read filehandle into the SV's IV slot), while set is called after an SV has been written to, in order to allow it to make use of its changed value (set on $/ copies the SV's new value to the PL_rs global variable).
Magic is implemented as a linked list of MAGIC structures attached to the SV. Each MAGIC struct holds the type of the magic, a pointer to an array of functions that implement the get(), set(), length() etc functions, plus space for some flags and pointers. For example, a tied variable has a MAGIC structure that contains a pointer to the object associated with the tie.
mg_clear
Clear something magical that the SV represents. See "sv_magic"
.
int mg_clear(SV *sv)
mg_copy
Copies the magic from one SV to another. See "sv_magic"
.
int mg_copy(SV *sv, SV *nsv, const char *key, I32 klen)
mg_find
Finds the magic pointer for type
matching the SV. See "sv_magic"
.
MAGIC * mg_find(const SV *sv, int type)
mg_findext
Finds the magic pointer of type
with the given vtbl
for the SV
. See "sv_magicext"
.
MAGIC * mg_findext(const SV *sv, int type, const MGVTBL *vtbl)
mg_free
Free any magic storage used by the SV. See "sv_magic"
.
int mg_free(SV *sv)
mg_freeext
Remove any magic of type how
using virtual table vtbl
from the SV sv
. See "sv_magic".
mg_freeext(sv, how, NULL)
is equivalent to mg_free_type(sv, how)
.
void mg_freeext(SV *sv, int how, const MGVTBL *vtbl)
mg_free_type
Remove any magic of type how
from the SV sv
. See "sv_magic".
void mg_free_type(SV *sv, int how)
mg_get
Do magic before a value is retrieved from the SV. The type of SV must be >= SVt_PVMG
. See "sv_magic"
.
int mg_get(SV *sv)
mg_magical
Turns on the magical status of an SV. See "sv_magic"
.
void mg_magical(SV *sv)
mg_set
Do magic after a value is assigned to the SV. See "sv_magic"
.
int mg_set(SV *sv)
PERL_MAGIC_arylen
PERL_MAGIC_arylen_p
PERL_MAGIC_backref
PERL_MAGIC_bm
PERL_MAGIC_checkcall
PERL_MAGIC_collxfrm
PERL_MAGIC_dbfile
PERL_MAGIC_dbline
PERL_MAGIC_debugvar
PERL_MAGIC_defelem
PERL_MAGIC_destruct
PERL_MAGIC_env
PERL_MAGIC_envelem
PERL_MAGIC_ext
PERL_MAGIC_extvalue
PERL_MAGIC_fm
PERL_MAGIC_hints
PERL_MAGIC_hintselem
PERL_MAGIC_hook
PERL_MAGIC_hookelem
PERL_MAGIC_isa
PERL_MAGIC_isaelem
PERL_MAGIC_lvref
PERL_MAGIC_nkeys
PERL_MAGIC_nonelem
PERL_MAGIC_overload_table
PERL_MAGIC_pos
PERL_MAGIC_qr
PERL_MAGIC_regdata
PERL_MAGIC_regdatum
PERL_MAGIC_regex_global
PERL_MAGIC_rhash
PERL_MAGIC_sig
PERL_MAGIC_sigelem
PERL_MAGIC_substr
PERL_MAGIC_sv
PERL_MAGIC_symtab
PERL_MAGIC_taint
PERL_MAGIC_tied
PERL_MAGIC_tiedelem
PERL_MAGIC_tiedscalar
PERL_MAGIC_utf8
PERL_MAGIC_uvar
PERL_MAGIC_uvar_elem
PERL_MAGIC_vec
PERL_MAGIC_vstring
Described in perlguts.
SvTIED_obj
Described in perlinterp.
SvTIED_obj(SV *sv, MAGIC *mg)
dump_mstats
When enabled by compiling with -DDEBUGGING_MSTATS
, print out statistics about malloc as two lines of numbers, one showing the length of the free list for each size category, the second showing the number of mallocs - frees for each size category.
s
, if not NULL, is used as a phrase to include in the output, such as "after compilation".
void dump_mstats(const char *s)
HASATTRIBUTE_MALLOC
Can we handle GCC
attribute for malloc-style functions.
HAS_MALLOC_GOOD_SIZE
This symbol, if defined, indicates that the malloc_good_size
routine is available for use.
HAS_MALLOC_SIZE
This symbol, if defined, indicates that the malloc_size
routine is available for use.
I_MALLOCMALLOC
This symbol, if defined, indicates to the C program that it should include malloc/malloc.h.
#ifdef I_MALLOCMALLOC
#include <mallocmalloc.h>
#endif
MYMALLOC
This symbol, if defined, indicates that we're using our own malloc.
Newx
safemalloc
The XSUB-writer's interface to the C malloc
function.
Memory obtained by this should ONLY be freed with "Safefree".
In 5.9.3, Newx() and friends replace the older New() API, and drops the first parameter, x, a debug aid which allowed callers to identify themselves. This aid has been superseded by a new build option, PERL_MEM_LOG (see "PERL_MEM_LOG" in perlhacktips). The older API is still there for use in XS modules supporting older perls.
void Newx (void* ptr, int nitems, type)
void* safemalloc(size_t size)
Newxc
The XSUB-writer's interface to the C malloc
function, with cast. See also "Newx"
.
Memory obtained by this should ONLY be freed with "Safefree".
void Newxc(void* ptr, int nitems, type, cast)
Newxz
safecalloc
The XSUB-writer's interface to the C calloc
function. The allocated memory is zeroed with memzero
. See also "Newx"
.
Memory obtained by this should ONLY be freed with "Safefree".
void Newxz (void* ptr, int nitems, type)
void* safecalloc(size_t nitems, size_t item_size)
PERL_MALLOC_WRAP
This symbol, if defined, indicates that we'd like malloc wrap checks.
Renew
saferealloc
The XSUB-writer's interface to the C realloc
function.
Memory obtained by this should ONLY be freed with "Safefree".
void Renew (void* ptr, int nitems, type)
void* saferealloc(void *ptr, size_t size)
Renewc
The XSUB-writer's interface to the C realloc
function, with cast.
Memory obtained by this should ONLY be freed with "Safefree".
void Renewc(void* ptr, int nitems, type, cast)
Safefree
The XSUB-writer's interface to the C free
function.
This should ONLY be used on memory obtained using "Newx" and friends.
void Safefree(void* ptr)
safesyscalloc
Safe version of system's calloc()
Malloc_t safesyscalloc(MEM_SIZE elements, MEM_SIZE size)
safesysfree
Safe version of system's free()
Free_t safesysfree(Malloc_t where)
safesysmalloc
Paranoid version of system's malloc()
Malloc_t safesysmalloc(MEM_SIZE nbytes)
safesysrealloc
Paranoid version of system's realloc()
Malloc_t safesysrealloc(Malloc_t where, MEM_SIZE nbytes)
These functions are related to the method resolution order of perl classes Also see perlmroapi.
HvMROMETA
Described in perlmroapi.
struct mro_meta * HvMROMETA(HV *hv)
mro_get_from_name
Returns the previously registered mro with the given name
, or NULL if not registered. See "mro_register
".
NOTE: mro_get_from_name
must be explicitly called as Perl_mro_get_from_name
with an aTHX_
parameter.
const struct mro_alg * Perl_mro_get_from_name(pTHX_ SV *name)
mro_get_linear_isa
Returns the mro linearisation for the given stash. By default, this will be whatever mro_get_linear_isa_dfs
returns unless some other MRO is in effect for the stash. The return value is a read-only AV* whose values are string SVs giving class names.
You are responsible for SvREFCNT_inc()
on the return value if you plan to store it anywhere semi-permanently (otherwise it might be deleted out from under you the next time the cache is invalidated).
AV * mro_get_linear_isa(HV *stash)
MRO_GET_PRIVATE_DATA
Described in perlmroapi.
SV* MRO_GET_PRIVATE_DATA(struct mro_meta *const smeta,
const struct mro_alg *const which)
mro_method_changed_in
Invalidates method caching on any child classes of the given stash, so that they might notice the changes in this one.
Ideally, all instances of PL_sub_generation++
in perl source outside of mro.c should be replaced by calls to this.
Perl automatically handles most of the common ways a method might be redefined. However, there are a few ways you could change a method in a stash without the cache code noticing, in which case you need to call this method afterwards:
1) Directly manipulating the stash HV entries from XS code.
2) Assigning a reference to a readonly scalar constant into a stash entry in order to create a constant subroutine (like constant.pm does).
This same method is available from pure perl via, mro::method_changed_in(classname)
.
void mro_method_changed_in(HV *stash)
mro_register
Registers a custom mro plugin. See perlmroapi for details on this and other mro functions.
NOTE: mro_register
must be explicitly called as Perl_mro_register
with an aTHX_
parameter.
void Perl_mro_register(pTHX_ const struct mro_alg *mro)
mro_set_mro
Set meta
to the value contained in the registered mro plugin whose name is name
.
Croaks if name
hasn't been registered
NOTE: mro_set_mro
must be explicitly called as Perl_mro_set_mro
with an aTHX_
parameter.
void Perl_mro_set_mro(pTHX_ struct mro_meta * const meta,
SV * const name)
mro_set_private_data
Described in perlmroapi.
NOTE: mro_set_private_data
must be explicitly called as Perl_mro_set_private_data
with an aTHX_
parameter.
SV * Perl_mro_set_private_data(pTHX_
struct mro_meta * const smeta,
const struct mro_alg * const which,
SV * const data)
dMULTICALL
Declare local variables for a multicall. See "LIGHTWEIGHT CALLBACKS" in perlcall.
dMULTICALL;
MULTICALL
Make a lightweight callback. See "LIGHTWEIGHT CALLBACKS" in perlcall.
MULTICALL;
POP_MULTICALL
Closing bracket for a lightweight callback. See "LIGHTWEIGHT CALLBACKS" in perlcall.
POP_MULTICALL;
PUSH_MULTICALL
Opening bracket for a lightweight callback. See "LIGHTWEIGHT CALLBACKS" in perlcall.
PUSH_MULTICALL(CV* the_cv);
Atol
DEPRECATED!
It is planned to remove Atol
from a future release of Perl. Do not use it for new code; remove it from existing code.
Described in perlhacktips.
Atol(const char * nptr)
Atoul
DEPRECATED!
It is planned to remove Atoul
from a future release of Perl. Do not use it for new code; remove it from existing code.
Described in perlhacktips.
Atoul(const char * nptr)
Drand01
This macro is to be used to generate uniformly distributed random numbers over the range [0., 1.[. You may have to supply an 'extern double drand48()
;' in your program since SunOS 4.1.3 doesn't provide you with anything relevant in its headers. See "HAS_DRAND48_PROTO"
.
double Drand01()
Gconvert
This preprocessor macro is defined to convert a floating point number to a string without a trailing decimal point. This emulates the behavior of sprintf("%g")
, but is sometimes much more efficient. If gconvert()
is not available, but gcvt()
drops the trailing decimal point, then gcvt()
is used. If all else fails, a macro using sprintf("%g")
is used. Arguments for the Gconvert macro are: value, number of digits, whether trailing zeros should be retained, and the output buffer. The usual values are:
d_Gconvert='gconvert((x),(n),(t),(b))'
d_Gconvert='gcvt((x),(n),(b))'
d_Gconvert='sprintf((b),"%.*g",(n),(x))'
The last two assume trailing zeros should not be kept.
char * Gconvert(double x, Size_t n, bool t, char * b)
grok_atoUV
parse a string, looking for a decimal unsigned integer.
On entry, pv
points to the beginning of the string; valptr
points to a UV that will receive the converted value, if found; endptr
is either NULL or points to a variable that points to one byte beyond the point in pv
that this routine should examine. If endptr
is NULL, pv
is assumed to be NUL-terminated.
Returns FALSE if pv
doesn't represent a valid unsigned integer value (with no leading zeros). Otherwise it returns TRUE, and sets *valptr
to that value.
If you constrain the portion of pv
that is looked at by this function (by passing a non-NULL endptr
), and if the initial bytes of that portion form a valid value, it will return TRUE, setting *endptr
to the byte following the final digit of the value. But if there is no constraint at what's looked at, all of pv
must be valid in order for TRUE to be returned. *endptr
is unchanged from its value on input if FALSE is returned;
The only characters this accepts are the decimal digits '0'..'9'.
As opposed to atoi(3) or strtol(3), grok_atoUV
does NOT allow optional leading whitespace, nor negative inputs. If such features are required, the calling code needs to explicitly implement those.
Note that this function returns FALSE for inputs that would overflow a UV, or have leading zeros. Thus a single 0
is accepted, but not 00
nor 01
, 002
, etc.
Background: atoi
has severe problems with illegal inputs, it cannot be used for incremental parsing, and therefore should be avoided atoi
and strtol
are also affected by locale settings, which can also be seen as a bug (global state controlled by user environment).
bool grok_atoUV(const char *pv, UV *valptr, const char **endptr)
grok_bin
converts a string representing a binary number to numeric form.
On entry start
and *len_p
give the string to scan, *flags
gives conversion flags, and result
should be NULL
or a pointer to an NV. The scan stops at the end of the string, or at just before the first invalid character. Unless PERL_SCAN_SILENT_ILLDIGIT
is set in *flags
, encountering an invalid character (except NUL) will also trigger a warning. On return *len_p
is set to the length of the scanned string, and *flags
gives output flags.
If the value is <= UV_MAX
it is returned as a UV, the output flags are clear, and nothing is written to *result
. If the value is > UV_MAX
, grok_bin
returns UV_MAX
, sets PERL_SCAN_GREATER_THAN_UV_MAX
in the output flags, and writes an approximation of the correct value into *result
(which is an NV; or the approximation is discarded if result
is NULL).
The binary number may optionally be prefixed with "0b"
or "b"
unless PERL_SCAN_DISALLOW_PREFIX
is set in *flags
on entry.
If PERL_SCAN_ALLOW_UNDERSCORES
is set in *flags
then any or all pairs of digits may be separated from each other by a single underscore; also a single leading underscore is accepted.
UV grok_bin(const char *start, STRLEN *len_p, I32 *flags,
NV *result)
grok_hex
converts a string representing a hex number to numeric form.
On entry start
and *len_p
give the string to scan, *flags
gives conversion flags, and result
should be NULL
or a pointer to an NV. The scan stops at the end of the string, or at just before the first invalid character. Unless PERL_SCAN_SILENT_ILLDIGIT
is set in *flags
, encountering an invalid character (except NUL) will also trigger a warning. On return *len_p
is set to the length of the scanned string, and *flags
gives output flags.
If the value is <= UV_MAX
it is returned as a UV, the output flags are clear, and nothing is written to *result
. If the value is > UV_MAX
, grok_hex
returns UV_MAX
, sets PERL_SCAN_GREATER_THAN_UV_MAX
in the output flags, and writes an approximation of the correct value into *result
(which is an NV; or the approximation is discarded if result
is NULL).
The hex number may optionally be prefixed with "0x"
or "x"
unless PERL_SCAN_DISALLOW_PREFIX
is set in *flags
on entry.
If PERL_SCAN_ALLOW_UNDERSCORES
is set in *flags
then any or all pairs of digits may be separated from each other by a single underscore; also a single leading underscore is accepted.
UV grok_hex(const char *start, STRLEN *len_p, I32 *flags,
NV *result)
grok_infnan
Helper for grok_number()
, accepts various ways of spelling "infinity" or "not a number", and returns one of the following flag combinations:
IS_NUMBER_INFINITY
IS_NUMBER_NAN
IS_NUMBER_INFINITY | IS_NUMBER_NEG
IS_NUMBER_NAN | IS_NUMBER_NEG
0
possibly |-ed with IS_NUMBER_TRAILING
.
If an infinity or a not-a-number is recognized, *sp
will point to one byte past the end of the recognized string. If the recognition fails, zero is returned, and *sp
will not move.
int grok_infnan(const char **sp, const char *send)
grok_number
Identical to grok_number_flags()
with flags
set to zero.
int grok_number(const char *pv, STRLEN len, UV *valuep)
grok_number_flags
Recognise (or not) a number. The type of the number is returned (0 if unrecognised), otherwise it is a bit-ORed combination of IS_NUMBER_IN_UV
, IS_NUMBER_GREATER_THAN_UV_MAX
, IS_NUMBER_NOT_INT
, IS_NUMBER_NEG
, IS_NUMBER_INFINITY
, IS_NUMBER_NAN
(defined in perl.h).
If the value of the number can fit in a UV, it is returned in *valuep
. IS_NUMBER_IN_UV
will be set to indicate that *valuep
is valid, IS_NUMBER_IN_UV
will never be set unless *valuep
is valid, but *valuep
may have been assigned to during processing even though IS_NUMBER_IN_UV
is not set on return. If valuep
is NULL
, IS_NUMBER_IN_UV
will be set for the same cases as when valuep
is non-NULL
, but no actual assignment (or SEGV) will occur.
IS_NUMBER_NOT_INT
will be set with IS_NUMBER_IN_UV
if trailing decimals were seen (in which case *valuep
gives the true value truncated to an integer), and IS_NUMBER_NEG
if the number is negative (in which case *valuep
holds the absolute value). IS_NUMBER_IN_UV
is not set if e
notation was used or the number is larger than a UV.
flags
allows only PERL_SCAN_TRAILING
, which allows for trailing non-numeric text on an otherwise successful grok, setting IS_NUMBER_TRAILING
on the result.
int grok_number_flags(const char *pv, STRLEN len, UV *valuep,
U32 flags)
GROK_NUMERIC_RADIX
A synonym for "grok_numeric_radix"
bool GROK_NUMERIC_RADIX(NN const char **sp, NN const char *send)
grok_numeric_radix
Scan and skip for a numeric decimal separator (radix).
bool grok_numeric_radix(const char **sp, const char *send)
grok_oct
converts a string representing an octal number to numeric form.
On entry start
and *len_p
give the string to scan, *flags
gives conversion flags, and result
should be NULL
or a pointer to an NV. The scan stops at the end of the string, or at just before the first invalid character. Unless PERL_SCAN_SILENT_ILLDIGIT
is set in *flags
, encountering an invalid character (except NUL) will also trigger a warning. On return *len_p
is set to the length of the scanned string, and *flags
gives output flags.
If the value is <= UV_MAX
it is returned as a UV, the output flags are clear, and nothing is written to *result
. If the value is > UV_MAX
, grok_oct
returns UV_MAX
, sets PERL_SCAN_GREATER_THAN_UV_MAX
in the output flags, and writes an approximation of the correct value into *result
(which is an NV; or the approximation is discarded if result
is NULL).
If PERL_SCAN_ALLOW_UNDERSCORES
is set in *flags
then any or all pairs of digits may be separated from each other by a single underscore; also a single leading underscore is accepted.
The PERL_SCAN_DISALLOW_PREFIX
flag is always treated as being set for this function.
UV grok_oct(const char *start, STRLEN *len_p, I32 *flags,
NV *result)
isinfnan
Perl_isinfnan()
is a utility function that returns true if the NV argument is either an infinity or a NaN
, false otherwise. To test in more detail, use Perl_isinf()
and Perl_isnan()
.
This is also the logical inverse of Perl_isfinite().
bool isinfnan(NV nv)
my_atof
atof
(3), but properly works with Perl locale handling, accepting a dot radix character always, but also the current locale's radix character if and only if called from within the lexical scope of a Perl use locale
statement.
N.B. s
must be NUL terminated.
NV my_atof(const char *s)
my_strtod
This function is equivalent to the libc strtod() function, and is available even on platforms that lack plain strtod(). Its return value is the best available precision depending on platform capabilities and Configure options.
It properly handles the locale radix character, meaning it expects a dot except when called from within the scope of use locale
, in which case the radix character should be that specified by the current locale.
The synonym Strtod() may be used instead.
NV my_strtod(const char * const s, char **e)
PERL_ABS
Typeless abs
or fabs
, etc. (The usage below indicates it is for integers, but it works for any type.) Use instead of these, since the C library ones force their argument to be what it is expecting, potentially leading to disaster. But also beware that this evaluates its argument twice, so no x++
.
int PERL_ABS(int x)
Perl_acos
Perl_asin
Perl_atan
Perl_atan2
Perl_ceil
Perl_cos
Perl_cosh
Perl_exp
Perl_floor
Perl_fmod
Perl_frexp
Perl_isfinite
Perl_isinf
Perl_isnan
Perl_ldexp
Perl_log
Perl_log10
Perl_modf
Perl_pow
Perl_sin
Perl_sinh
Perl_sqrt
Perl_tan
Perl_tanh
These perform the corresponding mathematical operation on the operand(s), using the libc function designed for the task that has just enough precision for an NV on this platform. If no such function with sufficient precision exists, the highest precision one available is used.
NV Perl_acos (NV x)
NV Perl_asin (NV x)
NV Perl_atan (NV x)
NV Perl_atan2 (NV x, NV y)
NV Perl_ceil (NV x)
NV Perl_cos (NV x)
NV Perl_cosh (NV x)
NV Perl_exp (NV x)
NV Perl_floor (NV x)
NV Perl_fmod (NV x, NV y)
NV Perl_frexp (NV x, int *exp)
IV Perl_isfinite(NV x)
IV Perl_isinf (NV x)
IV Perl_isnan (NV x)
NV Perl_ldexp (NV x, int exp)
NV Perl_log (NV x)
NV Perl_log10 (NV x)
NV Perl_modf (NV x, NV *iptr)
NV Perl_pow (NV x, NV y)
NV Perl_sin (NV x)
NV Perl_sinh (NV x)
NV Perl_sqrt (NV x)
NV Perl_tan (NV x)
NV Perl_tanh (NV x)
Perl_signbit
NOTE: Perl_signbit
is experimental and may change or be removed without notice.
Return a non-zero integer if the sign bit on an NV is set, and 0 if it is not.
If Configure detects this system has a signbit()
that will work with our NVs, then we just use it via the #define
in perl.h. Otherwise, fall back on this implementation. The main use of this function is catching -0.0
.
Configure
notes: This function is called 'Perl_signbit'
instead of a plain 'signbit'
because it is easy to imagine a system having a signbit()
function or macro that doesn't happen to work with our particular choice of NVs. We shouldn't just re-#define
signbit
as Perl_signbit
and expect the standard system headers to be happy. Also, this is a no-context function (no pTHX_
) because Perl_signbit()
is usually re-#defined
in perl.h as a simple macro call to the system's signbit()
. Users should just always call Perl_signbit()
.
int Perl_signbit(NV f)
PL_hexdigit
This array, indexed by an integer, converts that value into the character that represents it. For example, if the input is 8, the return will be a string whose first character is '8'. What is actually returned is a pointer into a string. All you are interested in is the first character of that string. To get uppercase letters (for the values 10..15), add 16 to the index. Hence, PL_hexdigit[11]
is 'b'
, and PL_hexdigit[11+16]
is 'B'
. Adding 16 to an index whose representation is '0'..'9' yields the same as not adding 16. Indices outside the range 0..31 result in (bad) undedefined behavior.
READ_XDIGIT
Returns the value of an ASCII-range hex digit and advances the string pointer. Behaviour is only well defined when isXDIGIT(*str) is true.
U8 READ_XDIGIT(char str*)
scan_bin
For backwards compatibility. Use grok_bin
instead.
NV scan_bin(const char *start, STRLEN len, STRLEN *retlen)
scan_hex
For backwards compatibility. Use grok_hex
instead.
NV scan_hex(const char *start, STRLEN len, STRLEN *retlen)
scan_oct
For backwards compatibility. Use grok_oct
instead.
NV scan_oct(const char *start, STRLEN len, STRLEN *retlen)
seedDrand01
This symbol defines the macro to be used in seeding the random number generator (see "Drand01"
).
void seedDrand01(Rand_seed_t x)
Strtod
This is a synonym for "my_strtod".
NV Strtod(NN const char * const s, NULLOK char ** e)
Strtol
Platform and configuration independent strtol
. This expands to the appropriate strotol
-like function based on the platform and Configure options>. For example it could expand to strtoll
or strtoq
instead of strtol
.
NV Strtol(NN const char * const s, NULLOK char ** e, int base)
Strtoul
Platform and configuration independent strtoul
. This expands to the appropriate strotoul
-like function based on the platform and Configure options>. For example it could expand to strtoull
or strtouq
instead of strtoul
.
NV Strtoul(NN const char * const s, NULLOK char ** e, int base)
alloccopstash
NOTE: alloccopstash
is experimental and may change or be removed without notice.
Available only under threaded builds, this function allocates an entry in PL_stashpad
for the stash passed to it.
PADOFFSET alloccopstash(HV *hv)
block_end
Handles compile-time scope exit. floor
is the savestack index returned by block_start
, and seq
is the body of the block. Returns the block, possibly modified.
OP * block_end(I32 floor, OP *seq)
block_start
Handles compile-time scope entry. Arranges for hints to be restored on block exit and also handles pad sequence numbers to make lexical variables scope right. Returns a savestack index for use with block_end
.
int block_start(int full)
ck_entersub_args_list
Performs the default fixup of the arguments part of an entersub
op tree. This consists of applying list context to each of the argument ops. This is the standard treatment used on a call marked with &
, or a method call, or a call through a subroutine reference, or any other call where the callee can't be identified at compile time, or a call where the callee has no prototype.
OP * ck_entersub_args_list(OP *entersubop)
ck_entersub_args_proto
Performs the fixup of the arguments part of an entersub
op tree based on a subroutine prototype. This makes various modifications to the argument ops, from applying context up to inserting refgen
ops, and checking the number and syntactic types of arguments, as directed by the prototype. This is the standard treatment used on a subroutine call, not marked with &
, where the callee can be identified at compile time and has a prototype.
protosv
supplies the subroutine prototype to be applied to the call. It may be a normal defined scalar, of which the string value will be used. Alternatively, for convenience, it may be a subroutine object (a CV*
that has been cast to SV*
) which has a prototype. The prototype supplied, in whichever form, does not need to match the actual callee referenced by the op tree.
If the argument ops disagree with the prototype, for example by having an unacceptable number of arguments, a valid op tree is returned anyway. The error is reflected in the parser state, normally resulting in a single exception at the top level of parsing which covers all the compilation errors that occurred. In the error message, the callee is referred to by the name defined by the namegv
parameter.
OP * ck_entersub_args_proto(OP *entersubop, GV *namegv,
SV *protosv)
ck_entersub_args_proto_or_list
Performs the fixup of the arguments part of an entersub
op tree either based on a subroutine prototype or using default list-context processing. This is the standard treatment used on a subroutine call, not marked with &
, where the callee can be identified at compile time.
protosv
supplies the subroutine prototype to be applied to the call, or indicates that there is no prototype. It may be a normal scalar, in which case if it is defined then the string value will be used as a prototype, and if it is undefined then there is no prototype. Alternatively, for convenience, it may be a subroutine object (a CV*
that has been cast to SV*
), of which the prototype will be used if it has one. The prototype (or lack thereof) supplied, in whichever form, does not need to match the actual callee referenced by the op tree.
If the argument ops disagree with the prototype, for example by having an unacceptable number of arguments, a valid op tree is returned anyway. The error is reflected in the parser state, normally resulting in a single exception at the top level of parsing which covers all the compilation errors that occurred. In the error message, the callee is referred to by the name defined by the namegv
parameter.
OP * ck_entersub_args_proto_or_list(OP *entersubop, GV *namegv,
SV *protosv)
cv_const_sv
If cv
is a constant sub eligible for inlining, returns the constant value returned by the sub. Otherwise, returns NULL
.
Constant subs can be created with newCONSTSUB
or as described in "Constant Functions" in perlsub.
SV * cv_const_sv(const CV * const cv)
cv_get_call_checker
The original form of "cv_get_call_checker_flags", which does not return checker flags. When using a checker function returned by this function, it is only safe to call it with a genuine GV as its namegv
argument.
void cv_get_call_checker(CV *cv, Perl_call_checker *ckfun_p,
SV **ckobj_p)
cv_get_call_checker_flags
Retrieves the function that will be used to fix up a call to cv
. Specifically, the function is applied to an entersub
op tree for a subroutine call, not marked with &
, where the callee can be identified at compile time as cv
.
The C-level function pointer is returned in *ckfun_p
, an SV argument for it is returned in *ckobj_p
, and control flags are returned in *ckflags_p
. The function is intended to be called in this manner:
entersubop = (*ckfun_p)(aTHX_ entersubop, namegv, (*ckobj_p));
In this call, entersubop
is a pointer to the entersub
op, which may be replaced by the check function, and namegv
supplies the name that should be used by the check function to refer to the callee of the entersub
op if it needs to emit any diagnostics. It is permitted to apply the check function in non-standard situations, such as to a call to a different subroutine or to a method call.
namegv
may not actually be a GV. If the CALL_CHECKER_REQUIRE_GV
bit is clear in *ckflags_p
, it is permitted to pass a CV or other SV instead, anything that can be used as the first argument to "cv_name". If the CALL_CHECKER_REQUIRE_GV
bit is set in *ckflags_p
then the check function requires namegv
to be a genuine GV.
By default, the check function is Perl_ck_entersub_args_proto_or_list, the SV parameter is cv
itself, and the CALL_CHECKER_REQUIRE_GV
flag is clear. This implements standard prototype processing. It can be changed, for a particular subroutine, by "cv_set_call_checker_flags".
If the CALL_CHECKER_REQUIRE_GV
bit is set in gflags
then it indicates that the caller only knows about the genuine GV version of namegv
, and accordingly the corresponding bit will always be set in *ckflags_p
, regardless of the check function's recorded requirements. If the CALL_CHECKER_REQUIRE_GV
bit is clear in gflags
then it indicates the caller knows about the possibility of passing something other than a GV as namegv
, and accordingly the corresponding bit may be either set or clear in *ckflags_p
, indicating the check function's recorded requirements.
gflags
is a bitset passed into cv_get_call_checker_flags
, in which only the CALL_CHECKER_REQUIRE_GV
bit currently has a defined meaning (for which see above). All other bits should be clear.
void cv_get_call_checker_flags(CV *cv, U32 gflags,
Perl_call_checker *ckfun_p,
SV **ckobj_p, U32 *ckflags_p)
cv_set_call_checker
The original form of "cv_set_call_checker_flags", which passes it the CALL_CHECKER_REQUIRE_GV
flag for backward-compatibility. The effect of that flag setting is that the check function is guaranteed to get a genuine GV as its namegv
argument.
void cv_set_call_checker(CV *cv, Perl_call_checker ckfun,
SV *ckobj)
cv_set_call_checker_flags
Sets the function that will be used to fix up a call to cv
. Specifically, the function is applied to an entersub
op tree for a subroutine call, not marked with &
, where the callee can be identified at compile time as cv
.
The C-level function pointer is supplied in ckfun
, an SV argument for it is supplied in ckobj
, and control flags are supplied in ckflags
. The function should be defined like this:
STATIC OP * ckfun(pTHX_ OP *op, GV *namegv, SV *ckobj)
It is intended to be called in this manner:
entersubop = ckfun(aTHX_ entersubop, namegv, ckobj);
In this call, entersubop
is a pointer to the entersub
op, which may be replaced by the check function, and namegv
supplies the name that should be used by the check function to refer to the callee of the entersub
op if it needs to emit any diagnostics. It is permitted to apply the check function in non-standard situations, such as to a call to a different subroutine or to a method call.
namegv
may not actually be a GV. For efficiency, perl may pass a CV or other SV instead. Whatever is passed can be used as the first argument to "cv_name". You can force perl to pass a GV by including CALL_CHECKER_REQUIRE_GV
in the ckflags
.
ckflags
is a bitset, in which only the CALL_CHECKER_REQUIRE_GV
bit currently has a defined meaning (for which see above). All other bits should be clear.
The current setting for a particular CV can be retrieved by "cv_get_call_checker_flags".
void cv_set_call_checker_flags(CV *cv, Perl_call_checker ckfun,
SV *ckobj, U32 ckflags)
finalize_optree
This function finalizes the optree. Should be called directly after the complete optree is built. It does some additional checking which can't be done in the normal ck_
xxx functions and makes the tree thread-safe.
void finalize_optree(OP *o)
forbid_outofblock_ops
NOTE: forbid_outofblock_ops
is experimental and may change or be removed without notice.
Checks an optree that implements a block, to ensure there are no control-flow ops that attempt to leave the block. Any OP_RETURN
is forbidden, as is any OP_GOTO
. Loops are analysed, so any LOOPEX op (OP_NEXT
, OP_LAST
or OP_REDO
) that affects a loop that contains it within the block are permitted, but those that do not are forbidden.
If any of these forbidden constructions are detected, an exception is thrown by using the op name and the blockname argument to construct a suitable message.
This function alone is not sufficient to ensure the optree does not perform any of these forbidden activities during runtime, as it might call a different function that performs a non-local LOOPEX, or a string-eval() that performs a goto
, or various other things. It is intended purely as a compile-time check for those that could be detected statically. Additional runtime checks may be required depending on the circumstance it is used for.
Note currently that all OP_GOTO
ops are forbidden, even in cases where they might otherwise be safe to execute. This may be permitted in a later version.
void forbid_outofblock_ops(OP *o, const char *blockname)
LINKLIST
Given the root of an optree, link the tree in execution order using the op_next
pointers and return the first op executed. If this has already been done, it will not be redone, and o->op_next
will be returned. If o->op_next
is not already set, o
should be at least an UNOP
.
OP* LINKLIST(OP *o)
newANONATTRSUB
Construct a nameless (anonymous) Perl subroutine, also performing some surrounding jobs.
This is the same as "newATTRSUB_x
" in perlintern with its o_is_gv
parameter set to FALSE, and its o
parameter to NULL. For more details, see "newATTRSUB_x
" in perlintern.
OP * newANONATTRSUB(I32 floor, OP *proto, OP *attrs, OP *block)
newANONHASH
Constructs, checks, and returns an anonymous hash op.
OP * newANONHASH(OP *o)
newANONLIST
Constructs, checks, and returns an anonymous list op.
OP * newANONLIST(OP *o)
newANONSUB
Construct a nameless (anonymous) Perl subroutine without attributes, also performing some surrounding jobs.
This is the same as "newATTRSUB_x
" in perlintern with its o_is_gv
parameter set to FALSE, and its o
and attrs
parameters to NULL. For more details, see "newATTRSUB_x
" in perlintern.
OP * newANONSUB(I32 floor, OP *proto, OP *block)
newARGDEFELEMOP
Constructs and returns a new OP_ARGDEFELEM
op which provides a defaulting expression given by expr
for the signature parameter at the index given by argindex
. The expression optree is consumed by this function and becomes part of the returned optree.
OP * newARGDEFELEMOP(I32 flags, OP *expr, I32 argindex)
newASSIGNOP
Constructs, checks, and returns an assignment op. left
and right
supply the parameters of the assignment; they are consumed by this function and become part of the constructed op tree.
If optype
is OP_ANDASSIGN
, OP_ORASSIGN
, or OP_DORASSIGN
, then a suitable conditional optree is constructed. If optype
is the opcode of a binary operator, such as OP_BIT_OR
, then an op is constructed that performs the binary operation and assigns the result to the left argument. Either way, if optype
is non-zero then flags
has no effect.
If optype
is zero, then a plain scalar or list assignment is constructed. Which type of assignment it is is automatically determined. flags
gives the eight bits of op_flags
, except that OPf_KIDS
will be set automatically, and, shifted up eight bits, the eight bits of op_private
, except that the bit with value 1 or 2 is automatically set as required.
OP * newASSIGNOP(I32 flags, OP *left, I32 optype, OP *right)
newATTRSUB
Construct a Perl subroutine, also performing some surrounding jobs, returning a pointer to the constructed subroutine.
This is the same as "newATTRSUB_x
" in perlintern with its o_is_gv
parameter set to FALSE. This means that if o
is null, the new sub will be anonymous; otherwise the name will be derived from o
in the way described (as with all other details) in "newATTRSUB_x
" in perlintern.
CV * newATTRSUB(I32 floor, OP *o, OP *proto, OP *attrs,
OP *block)
newAVREF
Constructs, checks, and returns an arrary reference op.
OP * newAVREF(OP *o)
newBINOP
Constructs, checks, and returns an op of any binary type. type
is the opcode. flags
gives the eight bits of op_flags
, except that OPf_KIDS
will be set automatically, and, shifted up eight bits, the eight bits of op_private
, except that the bit with value 1 or 2 is automatically set as required. first
and last
supply up to two ops to be the direct children of the binary op; they are consumed by this function and become part of the constructed op tree.
OP * newBINOP(I32 type, I32 flags, OP *first, OP *last)
newCONDOP
Constructs, checks, and returns a conditional-expression (cond_expr
) op. flags
gives the eight bits of op_flags
, except that OPf_KIDS
will be set automatically, and, shifted up eight bits, the eight bits of op_private
, except that the bit with value 1 is automatically set. first
supplies the expression selecting between the two branches, and trueop
and falseop
supply the branches; they are consumed by this function and become part of the constructed op tree.
OP * newCONDOP(I32 flags, OP *first, OP *trueop, OP *falseop)
newCONSTSUB
newCONSTSUB_flags
Construct a constant subroutine, also performing some surrounding jobs. A scalar constant-valued subroutine is eligible for inlining at compile-time, and in Perl code can be created by sub FOO () { 123 }
. Other kinds of constant subroutine have other treatment.
The subroutine will have an empty prototype and will ignore any arguments when called. Its constant behaviour is determined by sv
. If sv
is null, the subroutine will yield an empty list. If sv
points to a scalar, the subroutine will always yield that scalar. If sv
points to an array, the subroutine will always yield a list of the elements of that array in list context, or the number of elements in the array in scalar context. This function takes ownership of one counted reference to the scalar or array, and will arrange for the object to live as long as the subroutine does. If sv
points to a scalar then the inlining assumes that the value of the scalar will never change, so the caller must ensure that the scalar is not subsequently written to. If sv
points to an array then no such assumption is made, so it is ostensibly safe to mutate the array or its elements, but whether this is really supported has not been determined.
The subroutine will have CvFILE
set according to PL_curcop
. Other aspects of the subroutine will be left in their default state. The caller is free to mutate the subroutine beyond its initial state after this function has returned.
If name
is null then the subroutine will be anonymous, with its CvGV
referring to an __ANON__
glob. If name
is non-null then the subroutine will be named accordingly, referenced by the appropriate glob.
name
is a string, giving a sigilless symbol name. For /newCONSTSUB
, name
is NUL-terminated, interpreted as Latin-1.
For /newCONSTSUB_flags
, name
has length len
bytes, hence may contain embedded NULs. It is interpreted as UTF-8 if flags
has the SVf_UTF8
bit set, and Latin-1 otherwise. flags
should not have bits set other than SVf_UTF8
.
The name may be either qualified or unqualified. If the name is unqualified then it defaults to being in the stash specified by stash
if that is non-null, or to PL_curstash
if stash
is null. The symbol is always added to the stash if necessary, with GV_ADDMULTI
semantics.
If there is already a subroutine of the specified name, then the new sub will replace the existing one in the glob. A warning may be generated about the redefinition.
If the subroutine has one of a few special names, such as BEGIN
or END
, then it will be claimed by the appropriate queue for automatic running of phase-related subroutines. In this case the relevant glob will be left not containing any subroutine, even if it did contain one before. Execution of the subroutine will likely be a no-op, unless sv
was a tied array or the caller modified the subroutine in some interesting way before it was executed. In the case of BEGIN
, the treatment is buggy: the sub will be executed when only half built, and may be deleted prematurely, possibly causing a crash.
The function returns a pointer to the constructed subroutine. If the sub is anonymous then ownership of one counted reference to the subroutine is transferred to the caller. If the sub is named then the caller does not get ownership of a reference. In most such cases, where the sub has a non-phase name, the sub will be alive at the point it is returned by virtue of being contained in the glob that names it. A phase-named subroutine will usually be alive by virtue of the reference owned by the phase's automatic run queue. A BEGIN
subroutine may have been destroyed already by the time this function returns, but currently bugs occur in that case before the caller gets control. It is the caller's responsibility to ensure that it knows which of these situations applies.
CV * newCONSTSUB (HV *stash, const char *name, SV *sv)
CV * newCONSTSUB_flags(HV *stash, const char *name, STRLEN len,
U32 flags, SV *sv)
newCVREF
Constructs, checks, and returns a code reference op.
OP * newCVREF(I32 flags, OP *o)
newDEFEROP
NOTE: newDEFEROP
is experimental and may change or be removed without notice.
Constructs and returns a deferred-block statement that implements the defer
semantics. The block
optree is consumed by this function and becomes part of the returned optree.
The flags
argument carries additional flags to set on the returned op, including the op_private
field.
OP * newDEFEROP(I32 flags, OP *block)
newDEFSVOP
Constructs and returns an op to access $_
.
OP * newDEFSVOP()
newFOROP
Constructs, checks, and returns an op tree expressing a foreach
loop (iteration through a list of values). This is a heavyweight loop, with structure that allows exiting the loop by last
and suchlike.
sv
optionally supplies the variable(s) that will be aliased to each item in turn; if null, it defaults to $_
. expr
supplies the list of values to iterate over. block
supplies the main body of the loop, and cont
optionally supplies a continue
block that operates as a second half of the body. All of these optree inputs are consumed by this function and become part of the constructed op tree.
flags
gives the eight bits of op_flags
for the leaveloop
op and, shifted up eight bits, the eight bits of op_private
for the leaveloop
op, except that (in both cases) some bits will be set automatically.
OP * newFOROP(I32 flags, OP *sv, OP *expr, OP *block, OP *cont)
newGIVENOP
Constructs, checks, and returns an op tree expressing a given
block. cond
supplies the expression to whose value $_
will be locally aliased, and block
supplies the body of the given
construct; they are consumed by this function and become part of the constructed op tree. defsv_off
must be zero (it used to identity the pad slot of lexical $_).
OP * newGIVENOP(OP *cond, OP *block, PADOFFSET defsv_off)
newGVOP
Constructs, checks, and returns an op of any type that involves an embedded reference to a GV. type
is the opcode. flags
gives the eight bits of op_flags
. gv
identifies the GV that the op should reference; calling this function does not transfer ownership of any reference to it.
OP * newGVOP(I32 type, I32 flags, GV *gv)
newGVREF
Constructs, checks, and returns a glob reference op.
OP * newGVREF(I32 type, OP *o)
newHVREF
Constructs, checks, and returns a hash reference op.
OP * newHVREF(OP *o)
newLISTOP
Constructs, checks, and returns an op of any list type. type
is the opcode. flags
gives the eight bits of op_flags
, except that OPf_KIDS
will be set automatically if required. first
and last
supply up to two ops to be direct children of the list op; they are consumed by this function and become part of the constructed op tree.
For most list operators, the check function expects all the kid ops to be present already, so calling newLISTOP(OP_JOIN, ...)
(e.g.) is not appropriate. What you want to do in that case is create an op of type OP_LIST
, append more children to it, and then call "op_convert_list". See "op_convert_list" for more information.
If a compiletime-known fixed list of child ops is required, the "newLISTOPn" function can be used as a convenient shortcut, avoiding the need to create a temporary plain OP_LIST
in a new variable.
OP * newLISTOP(I32 type, I32 flags, OP *first, OP *last)
newLISTOPn
Constructs, checks, and returns an op of any list type. type
is the opcode. flags
gives the eight bits of op_flags
, except that OPf_KIDS
will be set automatically if required. The variable number of arguments after flags
must all be OP pointers, terminated by a final NULL
pointer. These will all be consumed as direct children of the list op and become part of the constructed op tree.
Do not forget to end the arguments list with a NULL
pointer.
This function is useful as a shortcut to performing the sequence of newLISTOP()
, op_append_elem()
on each element and final op_convert_list()
in the case where a compiletime-known fixed sequence of child ops is required. If a variable number of elements are required, or for splicing in an entire sub-list of child ops, see instead "newLISTOP" and "op_convert_list".
OP * newLISTOPn(I32 type, I32 flags, ...)
newLOGOP
Constructs, checks, and returns a logical (flow control) op. type
is the opcode. flags
gives the eight bits of op_flags
, except that OPf_KIDS
will be set automatically, and, shifted up eight bits, the eight bits of op_private
, except that the bit with value 1 is automatically set. first
supplies the expression controlling the flow, and other
supplies the side (alternate) chain of ops; they are consumed by this function and become part of the constructed op tree.
OP * newLOGOP(I32 optype, I32 flags, OP *first, OP *other)
newLOOPEX
Constructs, checks, and returns a loop-exiting op (such as goto
or last
). type
is the opcode. label
supplies the parameter determining the target of the op; it is consumed by this function and becomes part of the constructed op tree.
OP * newLOOPEX(I32 type, OP *label)
newLOOPOP
Constructs, checks, and returns an op tree expressing a loop. This is only a loop in the control flow through the op tree; it does not have the heavyweight loop structure that allows exiting the loop by last
and suchlike. flags
gives the eight bits of op_flags
for the top-level op, except that some bits will be set automatically as required. expr
supplies the expression controlling loop iteration, and block
supplies the body of the loop; they are consumed by this function and become part of the constructed op tree. debuggable
is currently unused and should always be 1.
OP * newLOOPOP(I32 flags, I32 debuggable, OP *expr, OP *block)
newMETHOP
Constructs, checks, and returns an op of method type with a method name evaluated at runtime. type
is the opcode. flags
gives the eight bits of op_flags
, except that OPf_KIDS
will be set automatically, and, shifted up eight bits, the eight bits of op_private
, except that the bit with value 1 is automatically set. dynamic_meth
supplies an op which evaluates method name; it is consumed by this function and become part of the constructed op tree. Supported optypes: OP_METHOD
.
OP * newMETHOP(I32 type, I32 flags, OP *dynamic_meth)
newMETHOP_named
Constructs, checks, and returns an op of method type with a constant method name. type
is the opcode. flags
gives the eight bits of op_flags
, and, shifted up eight bits, the eight bits of op_private
. const_meth
supplies a constant method name; it must be a shared COW string. Supported optypes: OP_METHOD_NAMED
.
OP * newMETHOP_named(I32 type, I32 flags, SV * const_meth)
newNULLLIST
Constructs, checks, and returns a new stub
op, which represents an empty list expression.
OP * newNULLLIST()
newOP
Constructs, checks, and returns an op of any base type (any type that has no extra fields). type
is the opcode. flags
gives the eight bits of op_flags
, and, shifted up eight bits, the eight bits of op_private
.
OP * newOP(I32 optype, I32 flags)
newPADOP
Constructs, checks, and returns an op of any type that involves a reference to a pad element. type
is the opcode. flags
gives the eight bits of op_flags
. A pad slot is automatically allocated, and is populated with sv
; this function takes ownership of one reference to it.
This function only exists if Perl has been compiled to use ithreads.
OP * newPADOP(I32 type, I32 flags, SV *sv)
newPMOP
Constructs, checks, and returns an op of any pattern matching type. type
is the opcode. flags
gives the eight bits of op_flags
and, shifted up eight bits, the eight bits of op_private
.
OP * newPMOP(I32 type, I32 flags)
newPVOP
Constructs, checks, and returns an op of any type that involves an embedded C-level pointer (PV). type
is the opcode. flags
gives the eight bits of op_flags
. pv
supplies the C-level pointer. Depending on the op type, the memory referenced by pv
may be freed when the op is destroyed. If the op is of a freeing type, pv
must have been allocated using PerlMemShared_malloc
.
OP * newPVOP(I32 type, I32 flags, char *pv)
newRANGE
Constructs and returns a range
op, with subordinate flip
and flop
ops. flags
gives the eight bits of op_flags
for the flip
op and, shifted up eight bits, the eight bits of op_private
for both the flip
and range
ops, except that the bit with value 1 is automatically set. left
and right
supply the expressions controlling the endpoints of the range; they are consumed by this function and become part of the constructed op tree.
OP * newRANGE(I32 flags, OP *left, OP *right)
newSLICEOP
Constructs, checks, and returns an lslice
(list slice) op. flags
gives the eight bits of op_flags
, except that OPf_KIDS
will be set automatically, and, shifted up eight bits, the eight bits of op_private
, except that the bit with value 1 or 2 is automatically set as required. listval
and subscript
supply the parameters of the slice; they are consumed by this function and become part of the constructed op tree.
OP * newSLICEOP(I32 flags, OP *subscript, OP *listop)
newSTATEOP
Constructs a state op (COP). The state op is normally a nextstate
op, but will be a dbstate
op if debugging is enabled for currently-compiled code. The state op is populated from PL_curcop
(or PL_compiling
). If label
is non-null, it supplies the name of a label to attach to the state op; this function takes ownership of the memory pointed at by label
, and will free it. flags
gives the eight bits of op_flags
for the state op.
If o
is null, the state op is returned. Otherwise the state op is combined with o
into a lineseq
list op, which is returned. o
is consumed by this function and becomes part of the returned op tree.
OP * newSTATEOP(I32 flags, char *label, OP *o)
newSUB
Construct a Perl subroutine without attributes, and also performing some surrounding jobs, returning a pointer to the constructed subroutine.
This is the same as "newATTRSUB_x
" in perlintern with its o_is_gv
parameter set to FALSE, and its attrs
parameter to NULL. This means that if o
is null, the new sub will be anonymous; otherwise the name will be derived from o
in the way described (as with all other details) in "newATTRSUB_x
" in perlintern.
CV * newSUB(I32 floor, OP *o, OP *proto, OP *block)
newSVOP
Constructs, checks, and returns an op of any type that involves an embedded SV. type
is the opcode. flags
gives the eight bits of op_flags
. sv
gives the SV to embed in the op; this function takes ownership of one reference to it.
OP * newSVOP(I32 type, I32 flags, SV *sv)
newSVREF
Constructs, checks, and returns a scalar reference op.
OP * newSVREF(OP *o)
newTRYCATCHOP
NOTE: newTRYCATCHOP
is experimental and may change or be removed without notice.
Constructs and returns a conditional execution statement that implements the try
/catch
semantics. First the op tree in tryblock
is executed, inside a context that traps exceptions. If an exception occurs then the optree in catchblock
is executed, with the trapped exception set into the lexical variable given by catchvar
(which must be an op of type OP_PADSV
). All the optrees are consumed by this function and become part of the returned op tree.
The flags
argument is currently ignored.
OP * newTRYCATCHOP(I32 flags, OP *tryblock, OP *catchvar,
OP *catchblock)
newUNOP
Constructs, checks, and returns an op of any unary type. type
is the opcode. flags
gives the eight bits of op_flags
, except that OPf_KIDS
will be set automatically if required, and, shifted up eight bits, the eight bits of op_private
, except that the bit with value 1 is automatically set. first
supplies an optional op to be the direct child of the unary op; it is consumed by this function and become part of the constructed op tree.
OP * newUNOP(I32 type, I32 flags, OP *first)
newUNOP_AUX
Similar to newUNOP
, but creates an UNOP_AUX
struct instead, with op_aux
initialised to aux
OP * newUNOP_AUX(I32 type, I32 flags, OP *first,
UNOP_AUX_item *aux)
newWHENOP
Constructs, checks, and returns an op tree expressing a when
block. cond
supplies the test expression, and block
supplies the block that will be executed if the test evaluates to true; they are consumed by this function and become part of the constructed op tree. cond
will be interpreted DWIMically, often as a comparison against $_
, and may be null to generate a default
block.
OP * newWHENOP(OP *cond, OP *block)
newWHILEOP
Constructs, checks, and returns an op tree expressing a while
loop. This is a heavyweight loop, with structure that allows exiting the loop by last
and suchlike.
loop
is an optional preconstructed enterloop
op to use in the loop; if it is null then a suitable op will be constructed automatically. expr
supplies the loop's controlling expression. block
supplies the main body of the loop, and cont
optionally supplies a continue
block that operates as a second half of the body. All of these optree inputs are consumed by this function and become part of the constructed op tree.
flags
gives the eight bits of op_flags
for the leaveloop
op and, shifted up eight bits, the eight bits of op_private
for the leaveloop
op, except that (in both cases) some bits will be set automatically. debuggable
is currently unused and should always be 1. has_my
can be supplied as true to force the loop body to be enclosed in its own scope.
OP * newWHILEOP(I32 flags, I32 debuggable, LOOP *loop, OP *expr,
OP *block, OP *cont, I32 has_my)
newXS
Used by xsubpp
to hook up XSUBs as Perl subs. filename
needs to be static storage, as it is used directly as CvFILE(), without a copy being made.
OA_BASEOP
OA_BINOP
OA_COP
OA_LISTOP
OA_LOGOP
OA_LOOP
OA_PADOP
OA_PMOP
OA_PVOP_OR_SVOP
OA_SVOP
OA_UNOP
Described in perlguts.
op_append_elem
Append an item to the list of ops contained directly within a list-type op, returning the lengthened list. first
is the list-type op, and last
is the op to append to the list. optype
specifies the intended opcode for the list. If first
is not already a list of the right type, it will be upgraded into one. If either first
or last
is null, the other is returned unchanged.
OP * op_append_elem(I32 optype, OP *first, OP *last)
op_append_list
Concatenate the lists of ops contained directly within two list-type ops, returning the combined list. first
and last
are the list-type ops to concatenate. optype
specifies the intended opcode for the list. If either first
or last
is not already a list of the right type, it will be upgraded into one. If either first
or last
is null, the other is returned unchanged.
OP * op_append_list(I32 optype, OP *first, OP *last)
OP_CLASS
Return the class of the provided OP: that is, which of the *OP structures it uses. For core ops this currently gets the information out of PL_opargs
, which does not always accurately reflect the type used; in v5.26 onwards, see also the function "op_class"
which can do a better job of determining the used type.
For custom ops the type is returned from the registration, and it is up to the registree to ensure it is accurate. The value returned will be one of the OA_
* constants from op.h.
U32 OP_CLASS(OP *o)
op_contextualize
Applies a syntactic context to an op tree representing an expression. o
is the op tree, and context
must be G_SCALAR
, G_LIST
, or G_VOID
to specify the context to apply. The modified op tree is returned.
OP * op_contextualize(OP *o, I32 context)
op_convert_list
Converts o
into a list op if it is not one already, and then converts it into the specified type
, calling its check function, allocating a target if it needs one, and folding constants.
A list-type op is usually constructed one kid at a time via newLISTOP
, op_prepend_elem
and op_append_elem
. Then finally it is passed to op_convert_list
to make it the right type.
OP * op_convert_list(I32 optype, I32 flags, OP *o)
OP_DESC
Return a short description of the provided OP.
const char * OP_DESC(OP *o)
op_force_list
Promotes o and any siblings to be an OP_LIST
if it is not already. If a new OP_LIST
op was created, its first child will be OP_PUSHMARK
. The returned node itself will be nulled, leaving only its children.
This is often what you want to do before putting the optree into list context; as
o = op_contextualize(op_force_list(o), G_LIST);
OP * op_force_list(OP *o)
op_free
Free an op and its children. Only use this when an op is no longer linked to from any optree.
Remember that any op with OPf_KIDS
set is expected to have a valid op_first
pointer. If you are attempting to free an op but preserve its child op, make sure to clear that flag before calling op_free()
. For example:
OP *kid = o->op_first; o->op_first = NULL;
o->op_flags &= ~OPf_KIDS;
op_free(o);
void op_free(OP *arg)
OpHAS_SIBLING
Returns true if o
has a sibling
bool OpHAS_SIBLING(OP *o)
OpLASTSIB_set
Marks o
as having no further siblings and marks o as having the specified parent. See also "OpMORESIB_set"
and OpMAYBESIB_set
. For a higher-level interface, see "op_sibling_splice"
.
void OpLASTSIB_set(OP *o, OP *parent)
op_linklist
This function is the implementation of the "LINKLIST" macro. It should not be called directly.
OP * op_linklist(OP *o)
op_lvalue
NOTE: op_lvalue
is experimental and may change or be removed without notice.
Propagate lvalue ("modifiable") context to an op and its children. type
represents the context type, roughly based on the type of op that would do the modifying, although local()
is represented by OP_NULL
, because it has no op type of its own (it is signalled by a flag on the lvalue op).
This function detects things that can't be modified, such as $x+1
, and generates errors for them. For example, $x+1 = 2
would cause it to be called with an op of type OP_ADD
and a type
argument of OP_SASSIGN
.
It also flags things that need to behave specially in an lvalue context, such as $$x = 5
which might have to vivify a reference in $x
.
OP * op_lvalue(OP *o, I32 type)
OpMAYBESIB_set
Conditionally does OpMORESIB_set
or OpLASTSIB_set
depending on whether sib
is non-null. For a higher-level interface, see "op_sibling_splice"
.
void OpMAYBESIB_set(OP *o, OP *sib, OP *parent)
OpMORESIB_set
Sets the sibling of o
to the non-zero value sib
. See also "OpLASTSIB_set"
and "OpMAYBESIB_set"
. For a higher-level interface, see "op_sibling_splice"
.
void OpMORESIB_set(OP *o, OP *sib)
OP_NAME
Return the name of the provided OP. For core ops this looks up the name from the op_type; for custom ops from the op_ppaddr.
const char * OP_NAME(OP *o)
op_null
Neutralizes an op when it is no longer needed, but is still linked to from other ops.
void op_null(OP *o)
op_parent
Returns the parent OP of o
, if it has a parent. Returns NULL
otherwise.
OP * op_parent(OP *o)
op_prepend_elem
Prepend an item to the list of ops contained directly within a list-type op, returning the lengthened list. first
is the op to prepend to the list, and last
is the list-type op. optype
specifies the intended opcode for the list. If last
is not already a list of the right type, it will be upgraded into one. If either first
or last
is null, the other is returned unchanged.
OP * op_prepend_elem(I32 optype, OP *first, OP *last)
op_scope
NOTE: op_scope
is experimental and may change or be removed without notice.
Wraps up an op tree with some additional ops so that at runtime a dynamic scope will be created. The original ops run in the new dynamic scope, and then, provided that they exit normally, the scope will be unwound. The additional ops used to create and unwind the dynamic scope will normally be an enter
/leave
pair, but a scope
op may be used instead if the ops are simple enough to not need the full dynamic scope structure.
OP * op_scope(OP *o)
OpSIBLING
Returns the sibling of o
, or NULL
if there is no sibling
OP* OpSIBLING(OP *o)
op_sibling_splice
A general function for editing the structure of an existing chain of op_sibling nodes. By analogy with the perl-level splice()
function, allows you to delete zero or more sequential nodes, replacing them with zero or more different nodes. Performs the necessary op_first/op_last housekeeping on the parent node and op_sibling manipulation on the children. The last deleted node will be marked as the last node by updating the op_sibling/op_sibparent or op_moresib field as appropriate.
Note that op_next is not manipulated, and nodes are not freed; that is the responsibility of the caller. It also won't create a new list op for an empty list etc; use higher-level functions like op_append_elem() for that.
parent
is the parent node of the sibling chain. It may passed as NULL
if the splicing doesn't affect the first or last op in the chain.
start
is the node preceding the first node to be spliced. Node(s) following it will be deleted, and ops will be inserted after it. If it is NULL
, the first node onwards is deleted, and nodes are inserted at the beginning.
del_count
is the number of nodes to delete. If zero, no nodes are deleted. If -1 or greater than or equal to the number of remaining kids, all remaining kids are deleted.
insert
is the first of a chain of nodes to be inserted in place of the nodes. If NULL
, no nodes are inserted.
The head of the chain of deleted ops is returned, or NULL
if no ops were deleted.
For example:
action before after returns
------ ----- ----- -------
P P
splice(P, A, 2, X-Y-Z) | | B-C
A-B-C-D A-X-Y-Z-D
P P
splice(P, NULL, 1, X-Y) | | A
A-B-C-D X-Y-B-C-D
P P
splice(P, NULL, 3, NULL) | | A-B-C
A-B-C-D D
P P
splice(P, B, 0, X-Y) | | NULL
A-B-C-D A-B-X-Y-C-D
For lower-level direct manipulation of op_sibparent
and op_moresib
, see "OpMORESIB_set"
, "OpLASTSIB_set"
, "OpMAYBESIB_set"
.
OP * op_sibling_splice(OP *parent, OP *start, int del_count,
OP *insert)
optimize_optree
This function applies some optimisations to the optree in top-down order. It is called before the peephole optimizer, which processes ops in execution order. Note that finalize_optree() also does a top-down scan, but is called *after* the peephole optimizer.
void optimize_optree(OP *o)
OP_TYPE_IS
Returns true if the given OP is not a NULL
pointer and if it is of the given type.
The negation of this macro, OP_TYPE_ISNT
is also available as well as OP_TYPE_IS_NN
and OP_TYPE_ISNT_NN
which elide the NULL pointer check.
bool OP_TYPE_IS(OP *o, Optype type)
OP_TYPE_IS_OR_WAS
Returns true if the given OP is not a NULL pointer and if it is of the given type or used to be before being replaced by an OP of type OP_NULL.
The negation of this macro, OP_TYPE_ISNT_AND_WASNT
is also available as well as OP_TYPE_IS_OR_WAS_NN
and OP_TYPE_ISNT_AND_WASNT_NN
which elide the NULL
pointer check.
bool OP_TYPE_IS_OR_WAS(OP *o, Optype type)
op_wrap_finally
NOTE: op_wrap_finally
is experimental and may change or be removed without notice.
Wraps the given block
optree fragment in its own scoped block, arranging for the finally
optree fragment to be invoked when leaving that block for any reason. Both optree fragments are consumed and the combined result is returned.
OP * op_wrap_finally(OP *block, OP *finally)
PL_opfreehook
When non-NULL
, the function pointed by this variable will be called each time an OP is freed with the corresponding OP as the argument. This allows extensions to free any extra attribute they have locally attached to an OP. It is also assured to first fire for the parent OP and then for its kids.
When you replace this variable, it is considered a good practice to store the possibly previously installed hook and that you recall it inside your own.
On threaded perls, each thread has an independent copy of this variable; each initialized at creation time with the current value of the creating thread's copy.
Perl_ophook_t PL_opfreehook
PL_peepp
Pointer to the per-subroutine peephole optimiser. This is a function that gets called at the end of compilation of a Perl subroutine (or equivalently independent piece of Perl code) to perform fixups of some ops and to perform small-scale optimisations. The function is called once for each subroutine that is compiled, and is passed, as sole parameter, a pointer to the op that is the entry point to the subroutine. It modifies the op tree in place.
The peephole optimiser should never be completely replaced. Rather, add code to it by wrapping the existing optimiser. The basic way to do this can be seen in "Compile pass 3: peephole optimization" in perlguts. If the new code wishes to operate on ops throughout the subroutine's structure, rather than just at the top level, it is likely to be more convenient to wrap the "PL_rpeepp" hook.
On threaded perls, each thread has an independent copy of this variable; each initialized at creation time with the current value of the creating thread's copy.
peep_t PL_peepp
PL_rpeepp
Pointer to the recursive peephole optimiser. This is a function that gets called at the end of compilation of a Perl subroutine (or equivalently independent piece of Perl code) to perform fixups of some ops and to perform small-scale optimisations. The function is called once for each chain of ops linked through their op_next
fields; it is recursively called to handle each side chain. It is passed, as sole parameter, a pointer to the op that is at the head of the chain. It modifies the op tree in place.
The peephole optimiser should never be completely replaced. Rather, add code to it by wrapping the existing optimiser. The basic way to do this can be seen in "Compile pass 3: peephole optimization" in perlguts. If the new code wishes to operate only on ops at a subroutine's top level, rather than throughout the structure, it is likely to be more convenient to wrap the "PL_peepp" hook.
On threaded perls, each thread has an independent copy of this variable; each initialized at creation time with the current value of the creating thread's copy.
peep_t PL_rpeepp
rv2cv_op_cv
Examines an op, which is expected to identify a subroutine at runtime, and attempts to determine at compile time which subroutine it identifies. This is normally used during Perl compilation to determine whether a prototype can be applied to a function call. cvop
is the op being considered, normally an rv2cv
op. A pointer to the identified subroutine is returned, if it could be determined statically, and a null pointer is returned if it was not possible to determine statically.
Currently, the subroutine can be identified statically if the RV that the rv2cv
is to operate on is provided by a suitable gv
or const
op. A gv
op is suitable if the GV's CV slot is populated. A const
op is suitable if the constant value must be an RV pointing to a CV. Details of this process may change in future versions of Perl. If the rv2cv
op has the OPpENTERSUB_AMPER
flag set then no attempt is made to identify the subroutine statically: this flag is used to suppress compile-time magic on a subroutine call, forcing it to use default runtime behaviour.
If flags
has the bit RV2CVOPCV_MARK_EARLY
set, then the handling of a GV reference is modified. If a GV was examined and its CV slot was found to be empty, then the gv
op has the OPpEARLY_CV
flag set. If the op is not optimised away, and the CV slot is later populated with a subroutine having a prototype, that flag eventually triggers the warning "called too early to check prototype".
If flags
has the bit RV2CVOPCV_RETURN_NAME_GV
set, then instead of returning a pointer to the subroutine it returns a pointer to the GV giving the most appropriate name for the subroutine in this context. Normally this is just the CvGV
of the subroutine, but for an anonymous (CvANON
) subroutine that is referenced through a GV it will be the referencing GV. The resulting GV*
is cast to CV*
to be returned. A null pointer is returned as usual if there is no statically-determinable subroutine.
CV * rv2cv_op_cv(OP *cvop, U32 flags)
packlist
The engine implementing pack()
Perl function.
void packlist(SV *cat, const char *pat, const char *patend,
SV **beglist, SV **endlist)
unpackstring
The engine implementing the unpack()
Perl function.
Using the template pat..patend
, this function unpacks the string s..strend
into a number of mortal SVs, which it pushes onto the perl argument (@_
) stack (so you will need to issue a PUTBACK
before and SPAGAIN
after the call to this function). It returns the number of pushed elements.
The strend
and patend
pointers should point to the byte following the last character of each string.
Although this function returns its values on the perl argument stack, it doesn't take any parameters from that stack (and thus in particular there's no need to do a PUSHMARK
before calling it, unlike "call_pv" for example).
SSize_t unpackstring(const char *pat, const char *patend,
const char *s, const char *strend,
U32 flags)
CvPADLIST
NOTE: CvPADLIST
is experimental and may change or be removed without notice.
CV's can have CvPADLIST(cv) set to point to a PADLIST. This is the CV's scratchpad, which stores lexical variables and opcode temporary and per-thread values.
For these purposes "formats" are a kind-of CV; eval""s are too (except they're not callable at will and are always thrown away after the eval"" is done executing). Require'd files are simply evals without any outer lexical scope.
XSUBs do not have a CvPADLIST
. dXSTARG
fetches values from PL_curpad
, but that is really the callers pad (a slot of which is allocated by every entersub). Do not get or set CvPADLIST
if a CV is an XSUB (as determined by CvISXSUB()
), CvPADLIST
slot is reused for a different internal purpose in XSUBs.
The PADLIST has a C array where pads are stored.
The 0th entry of the PADLIST is a PADNAMELIST which represents the "names" or rather the "static type information" for lexicals. The individual elements of a PADNAMELIST are PADNAMEs. Future refactorings might stop the PADNAMELIST from being stored in the PADLIST's array, so don't rely on it. See "PadlistNAMES".
The CvDEPTH'th entry of a PADLIST is a PAD (an AV) which is the stack frame at that depth of recursion into the CV. The 0th slot of a frame AV is an AV which is @_
. Other entries are storage for variables and op targets.
Iterating over the PADNAMELIST iterates over all possible pad items. Pad slots for targets (SVs_PADTMP
) and GVs end up having &PL_padname_undef "names", while slots for constants have &PL_padname_const
"names" (see "pad_alloc"
). That &PL_padname_undef
and &PL_padname_const
are used is an implementation detail subject to change. To test for them, use !PadnamePV(name)
and PadnamePV(name) && !PadnameLEN(name)
, respectively.
Only my
/our
variable slots get valid names. The rest are op targets/GVs/constants which are statically allocated or resolved at compile time. These don't have names by which they can be looked up from Perl code at run time through eval"" the way my
/our
variables can be. Since they can't be looked up by "name" but only by their index allocated at compile time (which is usually in PL_op->op_targ
), wasting a name SV for them doesn't make sense.
The pad names in the PADNAMELIST have their PV holding the name of the variable. The COP_SEQ_RANGE_LOW
and _HIGH
fields form a range (low+1..high inclusive) of cop_seq numbers for which the name is valid. During compilation, these fields may hold the special value PERL_PADSEQ_INTRO to indicate various stages:
COP_SEQ_RANGE_LOW _HIGH
----------------- -----
PERL_PADSEQ_INTRO 0 variable not yet introduced:
{ my ($x
valid-seq# PERL_PADSEQ_INTRO variable in scope:
{ my ($x);
valid-seq# valid-seq# compilation of scope complete:
{ my ($x); .... }
When a lexical var hasn't yet been introduced, it already exists from the perspective of duplicate declarations, but not for variable lookups, e.g.
my ($x, $x); # '"my" variable $x masks earlier declaration'
my $x = $x; # equal to my $x = $::x;
For typed lexicals PadnameTYPE
points at the type stash. For our
lexicals, PadnameOURSTASH
points at the stash of the associated global (so that duplicate our
declarations in the same package can be detected). PadnameGEN
is sometimes used to store the generation number during compilation.
If PadnameOUTER
is set on the pad name, then that slot in the frame AV is a REFCNT'ed reference to a lexical from "outside". Such entries are sometimes referred to as 'fake'. In this case, the name does not use 'low' and 'high' to store a cop_seq range, since it is in scope throughout. Instead 'high' stores some flags containing info about the real lexical (is it declared in an anon, and is it capable of being instantiated multiple times?), and for fake ANONs, 'low' contains the index within the parent's pad where the lexical's value is stored, to make cloning quicker.
If the 'name' is &
the corresponding entry in the PAD is a CV representing a possible closure.
Note that formats are treated as anon subs, and are cloned each time write is called (if necessary).
The flag SVs_PADSTALE
is cleared on lexicals each time the my()
is executed, and set on scope exit. This allows the "Variable $x is not available"
warning to be generated in evals, such as
{ my $x = 1; sub f { eval '$x'} } f();
For state vars, SVs_PADSTALE
is overloaded to mean 'not yet initialised', but this internal state is stored in a separate pad entry.
PADLIST * CvPADLIST(CV *cv)
pad_add_name_pvs
Exactly like "pad_add_name_pvn", but takes a literal string instead of a string/length pair.
PADOFFSET pad_add_name_pvs("name", U32 flags, HV *typestash,
HV *ourstash)
PadARRAY
NOTE: PadARRAY
is experimental and may change or be removed without notice.
The C array of pad entries.
SV ** PadARRAY(PAD * pad)
pad_findmy_pvs
Exactly like "pad_findmy_pvn", but takes a literal string instead of a string/length pair.
PADOFFSET pad_findmy_pvs("name", U32 flags)
PadlistARRAY
NOTE: PadlistARRAY
is experimental and may change or be removed without notice.
The C array of a padlist, containing the pads. Only subscript it with numbers >= 1, as the 0th entry is not guaranteed to remain usable.
PAD ** PadlistARRAY(PADLIST * padlist)
PadlistMAX
NOTE: PadlistMAX
is experimental and may change or be removed without notice.
The index of the last allocated space in the padlist. Note that the last pad may be in an earlier slot. Any entries following it will be NULL
in that case.
SSize_t PadlistMAX(PADLIST * padlist)
PadlistNAMES
NOTE: PadlistNAMES
is experimental and may change or be removed without notice.
The names associated with pad entries.
PADNAMELIST * PadlistNAMES(PADLIST * padlist)
PadlistNAMESARRAY
NOTE: PadlistNAMESARRAY
is experimental and may change or be removed without notice.
The C array of pad names.
PADNAME ** PadlistNAMESARRAY(PADLIST * padlist)
PadlistNAMESMAX
NOTE: PadlistNAMESMAX
is experimental and may change or be removed without notice.
The index of the last pad name.
SSize_t PadlistNAMESMAX(PADLIST * padlist)
PadlistREFCNT
NOTE: PadlistREFCNT
is experimental and may change or be removed without notice.
The reference count of the padlist. Currently this is always 1.
U32 PadlistREFCNT(PADLIST * padlist)
PadMAX
NOTE: PadMAX
is experimental and may change or be removed without notice.
The index of the last pad entry.
SSize_t PadMAX(PAD * pad)
PadnameLEN
NOTE: PadnameLEN
is experimental and may change or be removed without notice.
The length of the name.
STRLEN PadnameLEN(PADNAME * pn)
PadnamelistARRAY
NOTE: PadnamelistARRAY
is experimental and may change or be removed without notice.
The C array of pad names.
PADNAME ** PadnamelistARRAY(PADNAMELIST * pnl)
PadnamelistMAX
NOTE: PadnamelistMAX
is experimental and may change or be removed without notice.
The index of the last pad name.
SSize_t PadnamelistMAX(PADNAMELIST * pnl)
PadnamelistREFCNT
NOTE: PadnamelistREFCNT
is experimental and may change or be removed without notice.
The reference count of the pad name list.
SSize_t PadnamelistREFCNT(PADNAMELIST * pnl)
PadnamelistREFCNT_dec
NOTE: PadnamelistREFCNT_dec
is experimental and may change or be removed without notice.
Lowers the reference count of the pad name list.
void PadnamelistREFCNT_dec(PADNAMELIST * pnl)
PadnamePV
NOTE: PadnamePV
is experimental and may change or be removed without notice.
The name stored in the pad name struct. This returns NULL
for a target slot.
char * PadnamePV(PADNAME * pn)
PadnameREFCNT
NOTE: PadnameREFCNT
is experimental and may change or be removed without notice.
The reference count of the pad name.
SSize_t PadnameREFCNT(PADNAME * pn)
PadnameREFCNT_dec
NOTE: PadnameREFCNT_dec
is experimental and may change or be removed without notice.
Lowers the reference count of the pad name.
void PadnameREFCNT_dec(PADNAME * pn)
PadnameREFCNT_inc
NOTE: PadnameREFCNT_inc
is experimental and may change or be removed without notice.
Increases the reference count of the pad name. Returns the pad name itself.
PADNAME * PadnameREFCNT_inc(PADNAME * pn)
PadnameSV
NOTE: PadnameSV
is experimental and may change or be removed without notice.
Returns the pad name as a mortal SV.
SV * PadnameSV(PADNAME * pn)
PadnameUTF8
NOTE: PadnameUTF8
is experimental and may change or be removed without notice.
Whether PadnamePV is in UTF-8. Currently, this is always true.
bool PadnameUTF8(PADNAME * pn)
pad_new
Create a new padlist, updating the global variables for the currently-compiling padlist to point to the new padlist. The following flags can be OR'ed together:
padnew_CLONE this pad is for a cloned CV
padnew_SAVE save old globals on the save stack
padnew_SAVESUB also save extra stuff for start of sub
PADLIST * pad_new(int flags)
PL_comppad
NOTE: PL_comppad
is experimental and may change or be removed without notice.
During compilation, this points to the array containing the values part of the pad for the currently-compiling code. (At runtime a CV may have many such value arrays; at compile time just one is constructed.) At runtime, this points to the array containing the currently-relevant values for the pad for the currently-executing code.
PL_comppad_name
NOTE: PL_comppad_name
is experimental and may change or be removed without notice.
During compilation, this points to the array containing the names part of the pad for the currently-compiling code.
PL_curpad
NOTE: PL_curpad
is experimental and may change or be removed without notice.
Points directly to the body of the "PL_comppad" array. (I.e., this is PadARRAY(PL_comppad)
.)
SVs_PADMY
DEPRECATED!
It is planned to remove SVs_PADMY
from a future release of Perl. Do not use it for new code; remove it from existing code.
Described in perlguts.
GRPASSWD
This symbol, if defined, indicates to the C program that struct group
in grp.h contains gr_passwd
.
HAS_ENDGRENT
This symbol, if defined, indicates that the getgrent routine is available for finalizing sequential access of the group database.
HAS_ENDGRENT_R
This symbol, if defined, indicates that the endgrent_r
routine is available to endgrent re-entrantly.
HAS_ENDPWENT
This symbol, if defined, indicates that the endpwent
routine is available for finalizing sequential access of the passwd database.
HAS_ENDPWENT_R
This symbol, if defined, indicates that the endpwent_r
routine is available to endpwent re-entrantly.
HAS_GETGRENT
This symbol, if defined, indicates that the getgrent
routine is available for sequential access of the group database.
HAS_GETGRENT_R
This symbol, if defined, indicates that the getgrent_r
routine is available to getgrent re-entrantly.
HAS_GETPWENT
This symbol, if defined, indicates that the getpwent
routine is available for sequential access of the passwd database. If this is not available, the older getpw()
function may be available.
HAS_GETPWENT_R
This symbol, if defined, indicates that the getpwent_r
routine is available to getpwent re-entrantly.
HAS_SETGRENT
This symbol, if defined, indicates that the setgrent
routine is available for initializing sequential access of the group database.
HAS_SETGRENT_R
This symbol, if defined, indicates that the setgrent_r
routine is available to setgrent re-entrantly.
HAS_SETPWENT
This symbol, if defined, indicates that the setpwent
routine is available for initializing sequential access of the passwd database.
HAS_SETPWENT_R
This symbol, if defined, indicates that the setpwent_r
routine is available to setpwent re-entrantly.
PWAGE
This symbol, if defined, indicates to the C program that struct passwd
contains pw_age
.
PWCHANGE
This symbol, if defined, indicates to the C program that struct passwd
contains pw_change
.
PWCLASS
This symbol, if defined, indicates to the C program that struct passwd
contains pw_class
.
PWCOMMENT
This symbol, if defined, indicates to the C program that struct passwd
contains pw_comment
.
PWEXPIRE
This symbol, if defined, indicates to the C program that struct passwd
contains pw_expire
.
PWGECOS
This symbol, if defined, indicates to the C program that struct passwd
contains pw_gecos
.
PWPASSWD
This symbol, if defined, indicates to the C program that struct passwd
contains pw_passwd
.
PWQUOTA
This symbol, if defined, indicates to the C program that struct passwd
contains pw_quota
.
CSH
This symbol, if defined, contains the full pathname of csh.
LOC_SED
This symbol holds the complete pathname to the sed program.
SH_PATH
This symbol contains the full pathname to the shell used on this on this system to execute Bourne shell scripts. Usually, this will be /bin/sh, though it's possible that some systems will have /bin/ksh, /bin/pdksh, /bin/ash, /bin/bash, or even something such as D:/bin/sh.exe.
CRYPT_R_PROTO
This symbol encodes the prototype of crypt_r
. It is zero if d_crypt_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_crypt_r
is defined.
CTERMID_R_PROTO
This symbol encodes the prototype of ctermid_r
. It is zero if d_ctermid_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_ctermid_r
is defined.
DRAND48_R_PROTO
This symbol encodes the prototype of drand48_r
. It is zero if d_drand48_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_drand48_r
is defined.
ENDGRENT_R_PROTO
This symbol encodes the prototype of endgrent_r
. It is zero if d_endgrent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_endgrent_r
is defined.
ENDHOSTENT_R_PROTO
This symbol encodes the prototype of endhostent_r
. It is zero if d_endhostent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_endhostent_r
is defined.
ENDNETENT_R_PROTO
This symbol encodes the prototype of endnetent_r
. It is zero if d_endnetent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_endnetent_r
is defined.
ENDPROTOENT_R_PROTO
This symbol encodes the prototype of endprotoent_r
. It is zero if d_endprotoent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_endprotoent_r
is defined.
ENDPWENT_R_PROTO
This symbol encodes the prototype of endpwent_r
. It is zero if d_endpwent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_endpwent_r
is defined.
ENDSERVENT_R_PROTO
This symbol encodes the prototype of endservent_r
. It is zero if d_endservent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_endservent_r
is defined.
GDBMNDBM_H_USES_PROTOTYPES
This symbol, if defined, indicates that gdbm/ndbm.h uses real ANSI
C prototypes instead of K&R style function declarations without any parameter information. While ANSI
C prototypes are supported in C++, K&R style function declarations will yield errors.
GDBM_NDBM_H_USES_PROTOTYPES
This symbol, if defined, indicates that <gdbm-ndbm.h> uses real ANSI
C prototypes instead of K&R style function declarations without any parameter information. While ANSI
C prototypes are supported in C++, K&R style function declarations will yield errors.
GETGRENT_R_PROTO
This symbol encodes the prototype of getgrent_r
. It is zero if d_getgrent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_getgrent_r
is defined.
GETGRGID_R_PROTO
This symbol encodes the prototype of getgrgid_r
. It is zero if d_getgrgid_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_getgrgid_r
is defined.
GETGRNAM_R_PROTO
This symbol encodes the prototype of getgrnam_r
. It is zero if d_getgrnam_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_getgrnam_r
is defined.
GETHOSTBYADDR_R_PROTO
This symbol encodes the prototype of gethostbyaddr_r
. It is zero if d_gethostbyaddr_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_gethostbyaddr_r
is defined.
GETHOSTBYNAME_R_PROTO
This symbol encodes the prototype of gethostbyname_r
. It is zero if d_gethostbyname_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_gethostbyname_r
is defined.
GETHOSTENT_R_PROTO
This symbol encodes the prototype of gethostent_r
. It is zero if d_gethostent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_gethostent_r
is defined.
GETLOGIN_R_PROTO
This symbol encodes the prototype of getlogin_r
. It is zero if d_getlogin_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_getlogin_r
is defined.
GETNETBYADDR_R_PROTO
This symbol encodes the prototype of getnetbyaddr_r
. It is zero if d_getnetbyaddr_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_getnetbyaddr_r
is defined.
GETNETBYNAME_R_PROTO
This symbol encodes the prototype of getnetbyname_r
. It is zero if d_getnetbyname_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_getnetbyname_r
is defined.
GETNETENT_R_PROTO
This symbol encodes the prototype of getnetent_r
. It is zero if d_getnetent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_getnetent_r
is defined.
GETPROTOBYNAME_R_PROTO
This symbol encodes the prototype of getprotobyname_r
. It is zero if d_getprotobyname_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_getprotobyname_r
is defined.
GETPROTOBYNUMBER_R_PROTO
This symbol encodes the prototype of getprotobynumber_r
. It is zero if d_getprotobynumber_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_getprotobynumber_r
is defined.
GETPROTOENT_R_PROTO
This symbol encodes the prototype of getprotoent_r
. It is zero if d_getprotoent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_getprotoent_r
is defined.
GETPWENT_R_PROTO
This symbol encodes the prototype of getpwent_r
. It is zero if d_getpwent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_getpwent_r
is defined.
GETPWNAM_R_PROTO
This symbol encodes the prototype of getpwnam_r
. It is zero if d_getpwnam_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_getpwnam_r
is defined.
GETPWUID_R_PROTO
This symbol encodes the prototype of getpwuid_r
. It is zero if d_getpwuid_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_getpwuid_r
is defined.
GETSERVBYNAME_R_PROTO
This symbol encodes the prototype of getservbyname_r
. It is zero if d_getservbyname_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_getservbyname_r
is defined.
GETSERVBYPORT_R_PROTO
This symbol encodes the prototype of getservbyport_r
. It is zero if d_getservbyport_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_getservbyport_r
is defined.
GETSERVENT_R_PROTO
This symbol encodes the prototype of getservent_r
. It is zero if d_getservent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_getservent_r
is defined.
GETSPNAM_R_PROTO
This symbol encodes the prototype of getspnam_r
. It is zero if d_getspnam_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_getspnam_r
is defined.
HAS_DBMINIT_PROTO
This symbol, if defined, indicates that the system provides a prototype for the dbminit()
function. Otherwise, it is up to the program to supply one. A good guess is
extern int dbminit(char *);
HAS_DRAND48_PROTO
This symbol, if defined, indicates that the system provides a prototype for the drand48()
function. Otherwise, it is up to the program to supply one. A good guess is
extern double drand48(void);
HAS_FLOCK_PROTO
This symbol, if defined, indicates that the system provides a prototype for the flock()
function. Otherwise, it is up to the program to supply one. A good guess is
extern int flock(int, int);
HAS_GETHOST_PROTOS
This symbol, if defined, indicates that netdb.h includes prototypes for gethostent()
, gethostbyname()
, and gethostbyaddr()
. Otherwise, it is up to the program to guess them. See netdbtype.U (part of metaconfig) for probing for various Netdb_xxx_t
types.
HAS_GETNET_PROTOS
This symbol, if defined, indicates that netdb.h includes prototypes for getnetent()
, getnetbyname()
, and getnetbyaddr()
. Otherwise, it is up to the program to guess them. See netdbtype.U (part of metaconfig) for probing for various Netdb_xxx_t
types.
HAS_GETPROTO_PROTOS
This symbol, if defined, indicates that netdb.h includes prototypes for getprotoent()
, getprotobyname()
, and getprotobyaddr()
. Otherwise, it is up to the program to guess them. See netdbtype.U (part of metaconfig) for probing for various Netdb_xxx_t
types.
HAS_GETSERV_PROTOS
This symbol, if defined, indicates that netdb.h includes prototypes for getservent()
, getservbyname()
, and getservbyaddr()
. Otherwise, it is up to the program to guess them. See netdbtype.U (part of metaconfig) for probing for various Netdb_xxx_t
types.
HAS_MODFL_PROTO
This symbol, if defined, indicates that the system provides a prototype for the modfl()
function. Otherwise, it is up to the program to supply one.
HAS_SBRK_PROTO
This symbol, if defined, indicates that the system provides a prototype for the sbrk()
function. Otherwise, it is up to the program to supply one. Good guesses are
extern void* sbrk(int);
extern void* sbrk(size_t);
HAS_SETRESGID_PROTO
This symbol, if defined, indicates that the system provides a prototype for the setresgid()
function. Otherwise, it is up to the program to supply one. Good guesses are
extern int setresgid(uid_t ruid, uid_t euid, uid_t suid);
HAS_SETRESUID_PROTO
This symbol, if defined, indicates that the system provides a prototype for the setresuid()
function. Otherwise, it is up to the program to supply one. Good guesses are
extern int setresuid(uid_t ruid, uid_t euid, uid_t suid);
HAS_SHMAT_PROTOTYPE
This symbol, if defined, indicates that the sys/shm.h includes a prototype for shmat()
. Otherwise, it is up to the program to guess one. Shmat_t
shmat(int, Shmat_t, int)
is a good guess, but not always right so it should be emitted by the program only when HAS_SHMAT_PROTOTYPE
is not defined to avoid conflicting defs.
HAS_SOCKATMARK_PROTO
This symbol, if defined, indicates that the system provides a prototype for the sockatmark()
function. Otherwise, it is up to the program to supply one. A good guess is
extern int sockatmark(int);
HAS_SYSCALL_PROTO
This symbol, if defined, indicates that the system provides a prototype for the syscall()
function. Otherwise, it is up to the program to supply one. Good guesses are
extern int syscall(int, ...);
extern int syscall(long, ...);
HAS_TELLDIR_PROTO
This symbol, if defined, indicates that the system provides a prototype for the telldir()
function. Otherwise, it is up to the program to supply one. A good guess is
extern long telldir(DIR*);
NDBM_H_USES_PROTOTYPES
This symbol, if defined, indicates that ndbm.h uses real ANSI
C prototypes instead of K&R style function declarations without any parameter information. While ANSI
C prototypes are supported in C++, K&R style function declarations will yield errors.
RANDOM_R_PROTO
This symbol encodes the prototype of random_r
. It is zero if d_random_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_random_r
is defined.
READDIR_R_PROTO
This symbol encodes the prototype of readdir_r
. It is zero if d_readdir_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_readdir_r
is defined.
SETGRENT_R_PROTO
This symbol encodes the prototype of setgrent_r
. It is zero if d_setgrent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_setgrent_r
is defined.
SETHOSTENT_R_PROTO
This symbol encodes the prototype of sethostent_r
. It is zero if d_sethostent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_sethostent_r
is defined.
SETLOCALE_R_PROTO
This symbol encodes the prototype of setlocale_r
. It is zero if d_setlocale_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_setlocale_r
is defined.
SETNETENT_R_PROTO
This symbol encodes the prototype of setnetent_r
. It is zero if d_setnetent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_setnetent_r
is defined.
SETPROTOENT_R_PROTO
This symbol encodes the prototype of setprotoent_r
. It is zero if d_setprotoent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_setprotoent_r
is defined.
SETPWENT_R_PROTO
This symbol encodes the prototype of setpwent_r
. It is zero if d_setpwent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_setpwent_r
is defined.
SETSERVENT_R_PROTO
This symbol encodes the prototype of setservent_r
. It is zero if d_setservent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_setservent_r
is defined.
SRANDOM_R_PROTO
This symbol encodes the prototype of srandom_r
. It is zero if d_srandom_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_srandom_r
is defined.
SRAND48_R_PROTO
This symbol encodes the prototype of srand48_r
. It is zero if d_srand48_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_srand48_r
is defined.
STRERROR_R_PROTO
This symbol encodes the prototype of strerror_r
. It is zero if d_strerror_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_strerror_r
is defined.
TMPNAM_R_PROTO
This symbol encodes the prototype of tmpnam_r
. It is zero if d_tmpnam_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_tmpnam_r
is defined.
TTYNAME_R_PROTO
This symbol encodes the prototype of ttyname_r
. It is zero if d_ttyname_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_ttyname_r
is defined.
Functions for pushing and pulling items on the stack when the stack is reference counted. They are intended as replacements for the old PUSHs, POPi, EXTEND etc pp macros within pp functions.
rpp_context
NOTE: rpp_context
is experimental and may change or be removed without notice.
Impose void, scalar or list context on the stack. First, pop extra
items off the stack, then when gimme
is: G_LIST
: return as-is. G_VOID
: pop everything back to mark
G_SCALAR
: move the top stack item (or &PL_sv_undef
if none) to mark+1
and free everything above it.
void rpp_context(SV **mark, U8 gimme, SSize_t extra)
rpp_extend
NOTE: rpp_extend
is experimental and may change or be removed without notice.
Ensures that there is space on the stack to push n
items, extending it if necessary.
void rpp_extend(SSize_t n)
rpp_invoke_xs
NOTE: rpp_invoke_xs
is experimental and may change or be removed without notice.
Call the XS function associated with cv
. Wraps the call if necessary to handle XS functions which are not aware of reference-counted stacks.
void rpp_invoke_xs(CV *cv)
rpp_is_lone
NOTE: rpp_is_lone
is experimental and may change or be removed without notice.
Indicates whether the stacked SV sv
(assumed to be not yet popped off the stack) is only kept alive due to a single reference from the argument stack and/or and the temps stack.
This can used for example to decide whether the copying of return values in rvalue context can be skipped, or whether it shouldn't be assigned to in lvalue context.
bool rpp_is_lone(SV *sv)
rpp_popfree_1_NN
NOTE: rpp_popfree_1_NN
is experimental and may change or be removed without notice.
A variant of rpp_popfree_1() which assumes that the pointer being popped off the stack is non-NULL.
void rpp_popfree_1_NN()
rpp_popfree_2_NN
NOTE: rpp_popfree_2_NN
is experimental and may change or be removed without notice.
A variant of rpp_popfree_2() which assumes that the two pointers being popped off the stack are non-NULL.
void rpp_popfree_2_NN()
rpp_popfree_to
NOTE: rpp_popfree_to
is experimental and may change or be removed without notice.
Pop and free all items on the argument stack above sp
. On return, PL_stack_sp
will be equal to sp
.
void rpp_popfree_to(SV **sp)
rpp_popfree_to_NN
NOTE: rpp_popfree_to_NN
is experimental and may change or be removed without notice.
A variant of rpp_popfree_to() which assumes that all the pointers being popped off the stack are non-NULL.
void rpp_popfree_to_NN(SV **sp)
rpp_popfree_1
NOTE: rpp_popfree_1
is experimental and may change or be removed without notice.
Pop and free the top item on the argument stack and update PL_stack_sp
.
void rpp_popfree_1()
rpp_popfree_2
NOTE: rpp_popfree_2
is experimental and may change or be removed without notice.
Pop and free the top two items on the argument stack and update PL_stack_sp
.
void rpp_popfree_2()
rpp_pop_1_norc
NOTE: rpp_pop_1_norc
is experimental and may change or be removed without notice.
Pop and return the top item off the argument stack and update PL_stack_sp
. It's similar to rpp_popfree_1(), except that it actually returns a value, and it doesn't decrement the SV's reference count. On non-PERL_RC_STACK
builds it actually increments the SV's reference count.
This is useful in cases where the popped value is immediately embedded somewhere e.g. via av_store(), allowing you skip decrementing and then immediately incrementing the reference count again (and risk prematurely freeing the SV if it had a RC of 1). On non-RC builds, the reference count bookkeeping still works too, which is why it should be used rather than a simple *PL_stack_sp--
.
SV * rpp_pop_1_norc()
rpp_push_1_norc
NOTE: rpp_push_1_norc
is experimental and may change or be removed without notice.
Push sv
onto the stack without incrementing its reference count, and update PL_stack_sp
. On non-PERL_RC_STACK builds, mortalise too.
This is most useful where an SV has just been created and already has a reference count of 1, but has not yet been anchored anywhere.
void rpp_push_1_norc(SV *sv)
rpp_push_1
rpp_push_IMM
rpp_push_2
rpp_xpush_1
rpp_xpush_IMM
rpp_xpush_2
NOTE: all these forms are experimental and may change or be removed without notice.
Push one or two SVs onto the stack, incrementing their reference counts and updating PL_stack_sp
. With the x
variants, it extends the stack first. The IMM
variants assume that the single argument is an immortal such as <&PL_sv_undef> and, for efficiency, will skip incrementing its reference count.
void rpp_push_1 (SV *sv)
void rpp_push_IMM (SV *sv)
void rpp_push_2 (SV *sv1, SV *sv2)
void rpp_xpush_1 (SV *sv)
void rpp_xpush_IMM(SV *sv)
void rpp_xpush_2 (SV *sv1, SV *sv2)
rpp_replace_at
NOTE: rpp_replace_at
is experimental and may change or be removed without notice.
Replace the SV at address sp within the stack with sv
, while suitably adjusting reference counts. Equivalent to *sp = sv
, except with proper reference count handling.
void rpp_replace_at(SV **sp, SV *sv)
rpp_replace_at_NN
NOTE: rpp_replace_at_NN
is experimental and may change or be removed without notice.
A variant of rpp_replace_at() which assumes that the SV pointer on the stack is non-NULL.
void rpp_replace_at_NN(SV **sp, SV *sv)
rpp_replace_at_norc
NOTE: rpp_replace_at_norc
is experimental and may change or be removed without notice.
Replace the SV at address sp within the stack with sv
, while suitably adjusting the reference count of the old SV. Equivalent to *sp = sv
, except with proper reference count handling.
sv
's reference count doesn't get incremented. On non-PERL_RC_STACK
builds, it gets mortalised too.
This is most useful where an SV has just been created and already has a reference count of 1, but has not yet been anchored anywhere.
void rpp_replace_at_norc(SV **sp, SV *sv)
rpp_replace_at_norc_NN
NOTE: rpp_replace_at_norc_NN
is experimental and may change or be removed without notice.
A variant of rpp_replace_at_norc() which assumes that the SV pointer on the stack is non-NULL.
void rpp_replace_at_norc_NN(SV **sp, SV *sv)
rpp_replace_1_1
rpp_replace_1_1_NN
rpp_replace_1_IMM_NN
NOTE: all these forms are experimental and may change or be removed without notice.
Replace the current top stack item with sv
, while suitably adjusting reference counts. Equivalent to rpp_popfree_1(); rpp_push_1(sv), but is more efficient and handles both SVs being the same.
The _NN
variant assumes that the pointer on the stack to the SV being freed is non-NULL.
The IMM_NN
variant is like the _NN
variant, but in addition, assumes that the single argument is an immortal such as <&PL_sv_undef> and, for efficiency, will skip incrementing its reference count.
void rpp_replace_1_1(SV *sv)
rpp_replace_2_1
rpp_replace_2_1_NN
rpp_replace_2_IMM_NN
NOTE: all these forms are experimental and may change or be removed without notice.
Replace the current top to stacks item with sv
, while suitably adjusting reference counts. Equivalent to rpp_popfree_2(); rpp_push_1(sv), but is more efficient and handles SVs being the same.
The _NN
variant assumes that the pointers on the stack to the SVs being freed are non-NULL.
The IMM_NN
variant is like the _NN
variant, but in addition, assumes that the single argument is an immortal such as <&PL_sv_undef> and, for efficiency, will skip incrementing its reference count.
void rpp_replace_2_1(SV *sv)
rpp_stack_is_rc
NOTE: rpp_stack_is_rc
is experimental and may change or be removed without notice.
Returns a boolean value indicating whether the stack is currently reference-counted. Note that if the stack is split (bottom half RC, top half non-RC), this function returns false, even if the top half currently contains zero items.
bool rpp_stack_is_rc()
rpp_try_AMAGIC_1
rpp_try_AMAGIC_2
NOTE: both forms are experimental and may change or be removed without notice.
Check whether either of the one or two SVs at the top of the stack is magical or a ref, and in either case handle it specially: invoke get magic, call an overload method, or replace a ref with a temporary numeric value, as appropriate. If this function returns true, it indicates that the correct return value is already on the stack. Intended to be used at the beginning of the PP function for unary or binary ops.
bool rpp_try_AMAGIC_1(int method, int flags)
XSPP_wrapped
NOTE: XSPP_wrapped
is experimental and may change or be removed without notice.
Declare and wrap a non-reference-counted PP-style function. On traditional perl builds where the stack isn't reference-counted, this just produces a function declaration like
OP * xsppw_name(pTHX)
Conversely, in ref-counted builds it creates xsppw_name() as a small wrapper function which calls the real function via a wrapper which processes the args and return values to ensure that reference counts are properly handled for code which uses old-style dSP, PUSHs(), POPs() etc, which don't adjust the reference counts of the items they manipulate.
xsppw_nargs indicates how many arguments the function consumes off the stack. It can be a constant value or an expression, such as
((PL_op->op_flags & OPf_STACKED) ? 2 : 1)
Alternatively if xsppw_nlists is 1, it indicates that the PP function consumes a list (or - rarely - if 2, consumes two lists, like pp_aassign()), as indicated by the top markstack position.
This is intended as a temporary fix when converting XS code to run under PERL_RC_STACK builds. In the longer term, the PP function should be rewritten to replace PUSHs() etc with rpp_push_1() etc.
XSPP_wrapped(xsppw_name, I32 xsppw_nargs, I32 xsppw_nlists)
pregcomp
Described in perlreguts.
REGEXP * pregcomp(SV * const pattern, const U32 flags)
pregexec
Described in perlreguts.
I32 pregexec(REGEXP * const prog, char *stringarg, char *strend,
char *strbeg, SSize_t minend, SV *screamer,
U32 nosave)
re_compile
Compile the regular expression pattern pattern
, returning a pointer to the compiled object for later matching with the internal regex engine.
This function is typically used by a custom regexp engine .comp()
function to hand off to the core regexp engine those patterns it doesn't want to handle itself (typically passing through the same flags it was called with). In almost all other cases, a regexp should be compiled by calling "pregcomp
" to compile using the currently active regexp engine.
If pattern
is already a REGEXP
, this function does nothing but return a pointer to the input. Otherwise the PV is extracted and treated like a string representing a pattern. See perlre.
The possible flags for rx_flags
are documented in perlreapi. Their names all begin with RXf_
.
REGEXP * re_compile(SV * const pattern, U32 orig_rx_flags)
re_dup_guts
Duplicate a regexp.
This routine is expected to clone a given regexp structure. It is only compiled under USE_ITHREADS.
After all of the core data stored in struct regexp is duplicated the regexp_engine.dupe
method is used to copy any private data stored in the *pprivate pointer. This allows extensions to handle any duplication they need to do.
void re_dup_guts(const REGEXP *sstr, REGEXP *dstr,
CLONE_PARAMS *param)
regexp_engine
When a regexp is compiled, its engine
field is then set to point at the appropriate structure, so that when it needs to be used Perl can find the right routines to do so.
In order to install a new regexp handler, $^H{regcomp}
is set to an integer which (when casted appropriately) resolves to one of these structures. When compiling, the comp
method is executed, and the resulting regexp
structure's engine field is expected to point back at the same structure.
The pTHX_ symbol in the definition is a macro used by Perl under threading to provide an extra argument to the routine holding a pointer back to the interpreter that is executing the regexp. So under threading all routines get an extra argument.
regmatch_info
Some basic information about the current match that is created by Perl_regexec_flags and then passed to regtry(), regmatch() etc. It is allocated as a local var on the stack, so nothing should be stored in it that needs preserving or clearing up on croak(). For that, see the aux_info and aux_info_eval members of the regmatch_state union.
RXapif_ALL
RXapif_CLEAR
RXapif_DELETE
RXapif_EXISTS
RXapif_FETCH
RXapif_FIRSTKEY
RXapif_NEXTKEY
RXapif_ONE
RXapif_REGNAME
RXapif_REGNAMES
RXapif_REGNAMES_COUNT
RXapif_SCALAR
RXapif_STORE
Described in perlreapi.
RX_BUFF_IDX_CARET_FULLMATCH
RX_BUFF_IDX_CARET_POSTMATCH
RX_BUFF_IDX_CARET_PREMATCH
RX_BUFF_IDX_FULLMATCH
RX_BUFF_IDX_POSTMATCH
RX_BUFF_IDX_PREMATCH
Described in perlreapi.
RXf_NO_INPLACE_SUBST
RXf_NULL
RXf_SKIPWHITE
RXf_SPLIT
RXf_START_ONLY
RXf_WHITE
Described in perlreapi.
RXf_PMf_EXTENDED
RXf_PMf_FOLD
RXf_PMf_KEEPCOPY
RXf_PMf_MULTILINE
RXf_PMf_SINGLELINE
Described in perlreapi.
SvRX
Convenience macro to get the REGEXP from a SV. This is approximately equivalent to the following snippet:
if (SvMAGICAL(sv))
mg_get(sv);
if (SvROK(sv))
sv = MUTABLE_SV(SvRV(sv));
if (SvTYPE(sv) == SVt_REGEXP)
return (REGEXP*) sv;
NULL
will be returned if a REGEXP* is not found.
REGEXP * SvRX(SV *sv)
SvRXOK
Returns a boolean indicating whether the SV (or the one it references) is a REGEXP.
If you want to do something with the REGEXP* later use SvRX instead and check for NULL.
bool SvRXOK(SV* sv)
These are used in the simple report generation feature of Perl. See perlform.
HAS_SIGINFO_SI_ADDR
This symbol, if defined, indicates that siginfo_t
has the si_addr
member
HAS_SIGINFO_SI_BAND
This symbol, if defined, indicates that siginfo_t
has the si_band
member
HAS_SIGINFO_SI_ERRNO
This symbol, if defined, indicates that siginfo_t
has the si_errno
member
HAS_SIGINFO_SI_PID
This symbol, if defined, indicates that siginfo_t
has the si_pid
member
HAS_SIGINFO_SI_STATUS
This symbol, if defined, indicates that siginfo_t
has the si_status
member
HAS_SIGINFO_SI_UID
This symbol, if defined, indicates that siginfo_t
has the si_uid
member
HAS_SIGINFO_SI_VALUE
This symbol, if defined, indicates that siginfo_t
has the si_value
member
PERL_SIGNALS_UNSAFE_FLAG
If this bit in PL_signals
is set, the system is uing the pre-Perl 5.8 unsafe signals. See "PERL_SIGNALS" in perlrun and "Deferred Signals (Safe Signals)" in perlipc.
U32 PERL_SIGNALS_UNSAFE_FLAG
rsignal
A wrapper for the C library functions sigaction(2) or signal(2). Use this instead of those libc functions, as the Perl version gives the safest available implementation, and knows things that interact with the rest of the perl interpreter.
Sighandler_t rsignal(int i, Sighandler_t t)
rsignal_state
Returns a the current signal handler for signal signo
. See "rsignal
".
Sighandler_t rsignal_state(int i)
Sigjmp_buf
This is the buffer type to be used with Sigsetjmp and Siglongjmp.
Siglongjmp
This macro is used in the same way as siglongjmp()
, but will invoke traditional longjmp()
if siglongjmp isn't available. See "HAS_SIGSETJMP"
.
void Siglongjmp(jmp_buf env, int val)
SIG_NAME
This symbol contains a list of signal names in order of signal number. This is intended to be used as a static array initialization, like this:
char *sig_name[] = { SIG_NAME };
The signals in the list are separated with commas, and each signal is surrounded by double quotes. There is no leading SIG
in the signal name, i.e. SIGQUIT
is known as "QUIT
". Gaps in the signal numbers (up to NSIG
) are filled in with NUMnn
, etc., where nn is the actual signal number (e.g. NUM37
). The signal number for sig_name[i]
is stored in sig_num[i]
. The last element is 0 to terminate the list with a NULL
. This corresponds to the 0 at the end of the sig_name_init
list. Note that this variable is initialized from the sig_name_init
, not from sig_name
(which is unused).
SIG_NUM
This symbol contains a list of signal numbers, in the same order as the SIG_NAME
list. It is suitable for static array initialization, as in:
int sig_num[] = { SIG_NUM };
The signals in the list are separated with commas, and the indices within that list and the SIG_NAME
list match, so it's easy to compute the signal name from a number or vice versa at the price of a small dynamic linear lookup. Duplicates are allowed, but are moved to the end of the list. The signal number corresponding to sig_name[i]
is sig_number[i]
. if (i < NSIG
) then sig_number[i]
== i. The last element is 0, corresponding to the 0 at the end of the sig_name_init
list. Note that this variable is initialized from the sig_num_init
, not from sig_num
(which is unused).
Sigsetjmp
This macro is used in the same way as sigsetjmp()
, but will invoke traditional setjmp()
if sigsetjmp isn't available. See "HAS_SIGSETJMP"
.
int Sigsetjmp(jmp_buf env, int savesigs)
SIG_SIZE
This variable contains the number of elements of the SIG_NAME
and SIG_NUM
arrays, excluding the final NULL
entry.
whichsig
whichsig_pv
whichsig_pvn
whichsig_sv
These all convert a signal name into its corresponding signal number; returning -1 if no corresponding number was found.
They differ only in the source of the signal name:
whichsig_pv
takes the name from the NUL
-terminated string starting at sig
.
whichsig
is merely a different spelling, a synonym, of whichsig_pv
.
whichsig_pvn
takes the name from the string starting at sig
, with length len
bytes.
whichsig_sv
takes the name from the PV stored in the SV sigsv
.
I32 whichsig (const char *sig)
I32 whichsig_pv (const char *sig)
I32 whichsig_pvn(const char *sig, STRLEN len)
I32 whichsig_sv (SV *sigsv)
These variables give details as to where various libraries, installation destinations, etc., go, as well as what various installation options were selected
ARCHLIB
This variable, if defined, holds the name of the directory in which the user wants to put architecture-dependent public library files for perl5. It is most often a local directory such as /usr/local/lib. Programs using this variable must be prepared to deal with filename expansion. If ARCHLIB
is the same as PRIVLIB
, it is not defined, since presumably the program already searches PRIVLIB
.
ARCHLIB_EXP
This symbol contains the ~name expanded version of ARCHLIB
, to be used in programs that are not prepared to deal with ~ expansion at run-time.
ARCHNAME
This symbol holds a string representing the architecture name. It may be used to construct an architecture-dependant pathname where library files may be held under a private library, for instance.
BIN
This symbol holds the path of the bin directory where the package will be installed. Program must be prepared to deal with ~name substitution.
BIN_EXP
This symbol is the filename expanded version of the BIN
symbol, for programs that do not want to deal with that at run-time.
INSTALL_USR_BIN_PERL
This symbol, if defined, indicates that Perl is to be installed also as /usr/bin/perl.
MULTIARCH
This symbol, if defined, signifies that the build process will produce some binary files that are going to be used in a cross-platform environment. This is the case for example with the NeXT "fat" binaries that contain executables for several CPUs
.
PERL_INC_VERSION_LIST
This variable specifies the list of subdirectories in over which perl.c:incpush()
and lib/lib.pm will automatically search when adding directories to @INC
, in a format suitable for a C initialization string. See the inc_version_list
entry in Porting/Glossary for more details.
PERL_OTHERLIBDIRS
This variable contains a colon-separated set of paths for the perl binary to search for additional library files or modules. These directories will be tacked to the end of @INC
. Perl will automatically search below each path for version- and architecture-specific directories. See "PERL_INC_VERSION_LIST"
for more details.
PERL_RELOCATABLE_INC
This symbol, if defined, indicates that we'd like to relocate entries in @INC
at run time based on the location of the perl binary.
PERL_TARGETARCH
This symbol, if defined, indicates the target architecture Perl has been cross-compiled to. Undefined if not a cross-compile.
PERL_USE_DEVEL
This symbol, if defined, indicates that Perl was configured with -Dusedevel
, to enable development features. This should not be done for production builds.
PERL_VENDORARCH
If defined, this symbol contains the name of a private library. The library is private in the sense that it needn't be in anyone's execution path, but it should be accessible by the world. It may have a ~ on the front. The standard distribution will put nothing in this directory. Vendors who distribute perl may wish to place their own architecture-dependent modules and extensions in this directory with
MakeMaker Makefile.PL INSTALLDIRS=vendor
or equivalent. See INSTALL
for details.
PERL_VENDORARCH_EXP
This symbol contains the ~name expanded version of PERL_VENDORARCH
, to be used in programs that are not prepared to deal with ~ expansion at run-time.
PERL_VENDORLIB_EXP
This symbol contains the ~name expanded version of VENDORLIB
, to be used in programs that are not prepared to deal with ~ expansion at run-time.
PERL_VENDORLIB_STEM
This define is PERL_VENDORLIB_EXP
with any trailing version-specific component removed. The elements in inc_version_list
(inc_version_list
.U (part of metaconfig)) can be tacked onto this variable to generate a list of directories to search.
PRIVLIB
This symbol contains the name of the private library for this package. The library is private in the sense that it needn't be in anyone's execution path, but it should be accessible by the world. The program should be prepared to do ~ expansion.
PRIVLIB_EXP
This symbol contains the ~name expanded version of PRIVLIB
, to be used in programs that are not prepared to deal with ~ expansion at run-time.
SITEARCH
This symbol contains the name of the private library for this package. The library is private in the sense that it needn't be in anyone's execution path, but it should be accessible by the world. The program should be prepared to do ~ expansion. The standard distribution will put nothing in this directory. After perl has been installed, users may install their own local architecture-dependent modules in this directory with
MakeMaker Makefile.PL
or equivalent. See INSTALL
for details.
SITEARCH_EXP
This symbol contains the ~name expanded version of SITEARCH
, to be used in programs that are not prepared to deal with ~ expansion at run-time.
SITELIB
This symbol contains the name of the private library for this package. The library is private in the sense that it needn't be in anyone's execution path, but it should be accessible by the world. The program should be prepared to do ~ expansion. The standard distribution will put nothing in this directory. After perl has been installed, users may install their own local architecture-independent modules in this directory with
MakeMaker Makefile.PL
or equivalent. See INSTALL
for details.
SITELIB_EXP
This symbol contains the ~name expanded version of SITELIB
, to be used in programs that are not prepared to deal with ~ expansion at run-time.
SITELIB_STEM
This define is SITELIB_EXP
with any trailing version-specific component removed. The elements in inc_version_list
(inc_version_list
.U (part of metaconfig)) can be tacked onto this variable to generate a list of directories to search.
STARTPERL
This variable contains the string to put in front of a perl script to make sure (one hopes) that it runs with perl and not some shell.
USE_64_BIT_ALL
This symbol, if defined, indicates that 64-bit integers should be used when available. If not defined, the native integers will be used (be they 32 or 64 bits). The maximal possible 64-bitness is employed: LP64 or ILP64
, meaning that you will be able to use more than 2 gigabytes of memory. This mode is even more binary incompatible than USE_64_BIT_INT
. You may not be able to run the resulting executable in a 32-bit CPU
at all or you may need at least to reboot your OS to 64-bit mode.
USE_64_BIT_INT
This symbol, if defined, indicates that 64-bit integers should be used when available. If not defined, the native integers will be employed (be they 32 or 64 bits). The minimal possible 64-bitness is used, just enough to get 64-bit integers into Perl. This may mean using for example "long longs", while your memory may still be limited to 2 gigabytes.
USE_BSD_GETPGRP
This symbol, if defined, indicates that getpgrp needs one arguments whereas USG
one needs none.
USE_BSD_SETPGRP
This symbol, if defined, indicates that setpgrp needs two arguments whereas USG
one needs none. See also "HAS_SETPGID"
for a POSIX
interface.
USE_C_BACKTRACE
This symbol, if defined, indicates that Perl should be built with support for backtrace.
USE_CPLUSPLUS
This symbol, if defined, indicates that a C++ compiler was used to compiled Perl and will be used to compile extensions.
USE_CROSS_COMPILE
This symbol, if defined, indicates that Perl is being cross-compiled.
USE_DTRACE
This symbol, if defined, indicates that Perl should be built with support for DTrace.
USE_DYNAMIC_LOADING
This symbol, if defined, indicates that dynamic loading of some sort is available.
USE_FAST_STDIO
This symbol, if defined, indicates that Perl should be built to use 'fast stdio'. Defaults to define in Perls 5.8 and earlier, to undef later.
USE_ITHREADS
This symbol, if defined, indicates that Perl should be built to use the interpreter-based threading implementation.
USE_KERN_PROC_PATHNAME
This symbol, if defined, indicates that we can use sysctl with KERN_PROC_PATHNAME
to get a full path for the executable, and hence convert $^X to an absolute path.
USE_LARGE_FILES
This symbol, if defined, indicates that large file support should be used when available.
USE_LONG_DOUBLE
This symbol, if defined, indicates that long doubles should be used when available.
USE_MORE_BITS
This symbol, if defined, indicates that 64-bit interfaces and long doubles should be used when available.
USE_NSGETEXECUTABLEPATH
This symbol, if defined, indicates that we can use _NSGetExecutablePath
and realpath to get a full path for the executable, and hence convert $^X to an absolute path.
USE_PERLIO
This symbol, if defined, indicates that the PerlIO abstraction should be used throughout. If not defined, stdio should be used in a fully backward compatible manner.
USE_QUADMATH
This symbol, if defined, indicates that the quadmath library should be used when available.
USE_REENTRANT_API
This symbol, if defined, indicates that Perl should try to use the various _r
versions of library functions. This is extremely experimental.
USE_SEMCTL_SEMID_DS
This symbol, if defined, indicates that struct semid_ds
* is used for semctl IPC_STAT
.
USE_SEMCTL_SEMUN
This symbol, if defined, indicates that union semun
is used for semctl IPC_STAT
.
USE_SITECUSTOMIZE
This symbol, if defined, indicates that sitecustomize should be used.
USE_SOCKS
This symbol, if defined, indicates that Perl should be built to use socks.
USE_STAT_BLOCKS
This symbol is defined if this system has a stat structure declaring st_blksize
and st_blocks
.
USE_STDIO_BASE
This symbol is defined if the _base
field (or similar) of the stdio FILE
structure can be used to access the stdio buffer for a file handle. If this is defined, then the FILE_base(fp)
macro will also be defined and should be used to access this field. Also, the FILE_bufsiz(fp)
macro will be defined and should be used to determine the number of bytes in the buffer. USE_STDIO_BASE
will never be defined unless USE_STDIO_PTR
is.
USE_STDIO_PTR
This symbol is defined if the _ptr
and _cnt
fields (or similar) of the stdio FILE
structure can be used to access the stdio buffer for a file handle. If this is defined, then the FILE_ptr(fp)
and FILE_cnt(fp)
macros will also be defined and should be used to access these fields.
USE_STRICT_BY_DEFAULT
This symbol, if defined, enables additional defaults. At this time it only enables implicit strict by default.
USE_THREADS
This symbol, if defined, indicates that Perl should be built to use threads. At present, it is a synonym for and USE_ITHREADS
, but eventually the source ought to be changed to use this to mean _any_
threading implementation.
HAS_SOCKADDR_IN6
This symbol, if defined, indicates the availability of struct sockaddr_in6
;
HAS_SOCKADDR_SA_LEN
This symbol, if defined, indicates that the struct sockaddr
structure has a member called sa_len
, indicating the length of the structure.
HAS_SOCKADDR_STORAGE
This symbol, if defined, indicates the availability of struct sockaddr_storage
;
HAS_SOCKATMARK
This symbol, if defined, indicates that the sockatmark
routine is available to test whether a socket is at the out-of-band mark.
HAS_SOCKET
This symbol, if defined, indicates that the BSD
socket
interface is supported.
HAS_SOCKETPAIR
This symbol, if defined, indicates that the BSD
socketpair()
call is supported.
HAS_SOCKS5_INIT
This symbol, if defined, indicates that the socks5_init
routine is available to initialize SOCKS
5.
I_SOCKS
This symbol, if defined, indicates that socks.h exists and should be included.
#ifdef I_SOCKS
#include <socks.h>
#endif
I_SYS_SOCKIO
This symbol, if defined, indicates the sys/sockio.h should be included to get socket ioctl options, like SIOCATMARK
.
#ifdef I_SYS_SOCKIO
#include <sys_sockio.h>
#endif
apply_builtin_cv_attributes
Given an OP_LIST containing attribute definitions, filter it for known builtin attributes to apply to the cv, returning a possibly-smaller list containing just the remaining ones.
OP * apply_builtin_cv_attributes(CV *cv, OP *attrlist)
filter_add
Described in perlfilter.
SV * filter_add(filter_t funcp, SV *datasv)
filter_del
Delete most recently added instance of the filter function argument
void filter_del(filter_t funcp)
filter_read
Described in perlfilter.
I32 filter_read(int idx, SV *buf_sv, int maxlen)
scan_vstring
Returns a pointer to the next character after the parsed vstring, as well as updating the passed in sv.
Function must be called like
sv = sv_2mortal(newSV(5));
s = scan_vstring(s,e,sv);
where s and e are the start and end of the string. The sv should already be large enough to store the vstring passed in, for performance reasons.
This function may croak if fatal warnings are enabled in the calling scope, hence the sv_2mortal in the example (to prevent a leak). Make sure to do SvREFCNT_inc afterwards if you use sv_2mortal.
char * scan_vstring(const char *s, const char * const e, SV *sv)
start_subparse
Set things up for parsing a subroutine.
If is_format
is non-zero, the input is to be considered a format sub (a specialised sub used to implement perl's format
feature); else a normal sub
.
flags
are added to the flags for PL_compcv
. flags
may include the CVf_IsMETHOD
bit, which causes the new subroutine to be a method.
This returns the value of PL_savestack_ix
that was in effect upon entry to the function;
I32 start_subparse(I32 is_format, U32 flags)
dMARK
Declare a stack marker variable, mark
, for the XSUB. See "MARK"
and "dORIGMARK"
.
dMARK;
dORIGMARK
Saves the original stack mark for the XSUB. See "ORIGMARK"
.
dORIGMARK;
dSP
Declares a local copy of perl's stack pointer for the XSUB, available via the SP
macro. See "SP"
.
dSP;
dTARGET
Declare that this function uses TARG
, and initializes it
dTARGET;
EXTEND
Used to extend the argument stack for an XSUB's return values. Once used, guarantees that there is room for at least nitems
to be pushed onto the stack.
void EXTEND(SP, SSize_t nitems)
mPUSHi
Push an integer onto the stack. The stack must have room for this element. Does not use TARG
. See also "PUSHi"
, "mXPUSHi"
and "XPUSHi"
.
void mPUSHi(IV iv)
mPUSHn
Push a double onto the stack. The stack must have room for this element. Does not use TARG
. See also "PUSHn"
, "mXPUSHn"
and "XPUSHn"
.
void mPUSHn(NV nv)
mPUSHp
Push a string onto the stack. The stack must have room for this element. The len
indicates the length of the string. Does not use TARG
. See also "PUSHp"
, "mXPUSHp"
and "XPUSHp"
.
void mPUSHp(char* str, STRLEN len)
mPUSHpvs
A variation on mPUSHp
that takes a literal string and calculates its size directly.
void mPUSHpvs("literal string")
mPUSHs
Push an SV onto the stack and mortalizes the SV. The stack must have room for this element. Does not use TARG
. See also "PUSHs"
and "mXPUSHs"
.
void mPUSHs(SV* sv)
mPUSHu
Push an unsigned integer onto the stack. The stack must have room for this element. Does not use TARG
. See also "PUSHu"
, "mXPUSHu"
and "XPUSHu"
.
void mPUSHu(UV uv)
mXPUSHi
Push an integer onto the stack, extending the stack if necessary. Does not use TARG
. See also "XPUSHi"
, "mPUSHi"
and "PUSHi"
.
void mXPUSHi(IV iv)
mXPUSHn
Push a double onto the stack, extending the stack if necessary. Does not use TARG
. See also "XPUSHn"
, "mPUSHn"
and "PUSHn"
.
void mXPUSHn(NV nv)
mXPUSHp
Push a string onto the stack, extending the stack if necessary. The len
indicates the length of the string. Does not use TARG
. See also "XPUSHp"
, mPUSHp
and PUSHp
.
void mXPUSHp(char* str, STRLEN len)
mXPUSHpvs
A variation on mXPUSHp
that takes a literal string and calculates its size directly.
void mXPUSHpvs("literal string")
mXPUSHs
Push an SV onto the stack, extending the stack if necessary and mortalizes the SV. Does not use TARG
. See also "XPUSHs"
and "mPUSHs"
.
void mXPUSHs(SV* sv)
mXPUSHu
Push an unsigned integer onto the stack, extending the stack if necessary. Does not use TARG
. See also "XPUSHu"
, "mPUSHu"
and "PUSHu"
.
void mXPUSHu(UV uv)
newXSproto
Used by xsubpp
to hook up XSUBs as Perl subs. Adds Perl prototypes to the subs.
ORIGMARK
The original stack mark for the XSUB. See "dORIGMARK"
.
POPi
Pops an integer off the stack.
IV POPi
POPl
Pops a long off the stack.
long POPl
POPn
Pops a double off the stack.
NV POPn
POPp
Pops a string off the stack.
char* POPp
POPpbytex
Pops a string off the stack which must consist of bytes i.e. characters < 256.
char* POPpbytex
POPpx
Pops a string off the stack. Identical to POPp. There are two names for historical reasons.
char* POPpx
POPs
Pops an SV off the stack.
SV* POPs
POPu
Pops an unsigned integer off the stack.
UV POPu
POPul
Pops an unsigned long off the stack.
long POPul
PUSHi
Push an integer onto the stack. The stack must have room for this element. Handles 'set' magic. Uses TARG
, so dTARGET
or dXSTARG
should be called to declare it. Do not call multiple TARG
-oriented macros to return lists from XSUB's - see "mPUSHi"
instead. See also "XPUSHi"
and "mXPUSHi"
.
void PUSHi(IV iv)
PUSHMARK
Opening bracket for arguments on a callback. See "PUTBACK"
and perlcall.
void PUSHMARK(SP)
PUSHmortal
Push a new mortal SV onto the stack. The stack must have room for this element. Does not use TARG
. See also "PUSHs"
, "XPUSHmortal"
and "XPUSHs"
.
void PUSHmortal
PUSHn
Push a double onto the stack. The stack must have room for this element. Handles 'set' magic. Uses TARG
, so dTARGET
or dXSTARG
should be called to declare it. Do not call multiple TARG
-oriented macros to return lists from XSUB's - see "mPUSHn"
instead. See also "XPUSHn"
and "mXPUSHn"
.
void PUSHn(NV nv)
PUSHp
Push a string onto the stack. The stack must have room for this element. The len
indicates the length of the string. Handles 'set' magic. Uses TARG
, so dTARGET
or dXSTARG
should be called to declare it. Do not call multiple TARG
-oriented macros to return lists from XSUB's - see "mPUSHp"
instead. See also "XPUSHp"
and "mXPUSHp"
.
void PUSHp(char* str, STRLEN len)
PUSHpvs
A variation on PUSHp
that takes a literal string and calculates its size directly.
void PUSHpvs("literal string")
PUSHs
Push an SV onto the stack. The stack must have room for this element. Does not handle 'set' magic. Does not use TARG
. See also "PUSHmortal"
, "XPUSHs"
, and "XPUSHmortal"
.
void PUSHs(SV* sv)
PUSHu
Push an unsigned integer onto the stack. The stack must have room for this element. Handles 'set' magic. Uses TARG
, so dTARGET
or dXSTARG
should be called to declare it. Do not call multiple TARG
-oriented macros to return lists from XSUB's - see "mPUSHu"
instead. See also "XPUSHu"
and "mXPUSHu"
.
void PUSHu(UV uv)
PUTBACK
Closing bracket for XSUB arguments. This is usually handled by xsubpp
. See "PUSHMARK"
and perlcall for other uses.
PUTBACK;
SSNEW
SSNEWa
SSNEWat
SSNEWt
These each temporarily allocate data on the savestack, returning an SSize_t index into the savestack, because a pointer would get broken if the savestack is moved on reallocation. Use "SSPTR
" to convert the returned index into a pointer.
The forms differ in that plain SSNEW
allocates size
bytes; SSNEWt
and SSNEWat
allocate size
objects, each of which is type type
; and <SSNEWa> and SSNEWat
make sure to align the new data to an align
boundary. The most useful value for the alignment is likely to be "MEM_ALIGNBYTES
". The alignment will be preserved through savestack reallocation only if realloc returns data aligned to a size divisible by "align"!
SSize_t SSNEW (Size_t size)
SSize_t SSNEWa (Size_t size, Size_t align)
SSize_t SSNEWat(Size_t size, type, Size_t align)
SSize_t SSNEWt (Size_t size, type)
SSPTR
SSPTRt
These convert the index
returned by L/<SSNEW
> and kin into actual pointers.
The difference is that SSPTR
casts the result to type
, and SSPTRt
casts it to a pointer of that type
.
type SSPTR (SSize_t index, type)
type * SSPTRt(SSize_t index, type)
TARG
TARG
is short for "target". It is an entry in the pad that an OPs op_targ
refers to. It is scratchpad space, often used as a return value for the OP, but some use it for other purposes.
TARG;
XPUSHi
Push an integer onto the stack, extending the stack if necessary. Handles 'set' magic. Uses TARG
, so dTARGET
or dXSTARG
should be called to declare it. Do not call multiple TARG
-oriented macros to return lists from XSUB's - see "mXPUSHi"
instead. See also "PUSHi"
and "mPUSHi"
.
void XPUSHi(IV iv)
XPUSHmortal
Push a new mortal SV onto the stack, extending the stack if necessary. Does not use TARG
. See also "XPUSHs"
, "PUSHmortal"
and "PUSHs"
.
void XPUSHmortal
XPUSHn
Push a double onto the stack, extending the stack if necessary. Handles 'set' magic. Uses TARG
, so dTARGET
or dXSTARG
should be called to declare it. Do not call multiple TARG
-oriented macros to return lists from XSUB's - see "mXPUSHn"
instead. See also "PUSHn"
and "mPUSHn"
.
void XPUSHn(NV nv)
XPUSHp
Push a string onto the stack, extending the stack if necessary. The len
indicates the length of the string. Handles 'set' magic. Uses TARG
, so dTARGET
or dXSTARG
should be called to declare it. Do not call multiple TARG
-oriented macros to return lists from XSUB's - see "mXPUSHp"
instead. See also "PUSHp"
and "mPUSHp"
.
void XPUSHp(char* str, STRLEN len)
XPUSHpvs
A variation on XPUSHp
that takes a literal string and calculates its size directly.
void XPUSHpvs("literal string")
XPUSHs
Push an SV onto the stack, extending the stack if necessary. Does not handle 'set' magic. Does not use TARG
. See also "XPUSHmortal"
, PUSHs
and PUSHmortal
.
void XPUSHs(SV* sv)
XPUSHu
Push an unsigned integer onto the stack, extending the stack if necessary. Handles 'set' magic. Uses TARG
, so dTARGET
or dXSTARG
should be called to declare it. Do not call multiple TARG
-oriented macros to return lists from XSUB's - see "mXPUSHu"
instead. See also "PUSHu"
and "mPUSHu"
.
void XPUSHu(UV uv)
XS_APIVERSION_BOOTCHECK
Macro to verify that the perl api version an XS module has been compiled against matches the api version of the perl interpreter it's being loaded into.
XS_APIVERSION_BOOTCHECK;
XSRETURN
Return from XSUB, indicating number of items on the stack. This is usually handled by xsubpp
.
void XSRETURN(int nitems)
XSRETURN_EMPTY
Return an empty list from an XSUB immediately.
XSRETURN_EMPTY;
XSRETURN_IV
Return an integer from an XSUB immediately. Uses XST_mIV
.
void XSRETURN_IV(IV iv)
XSRETURN_NO
Return &PL_sv_no
from an XSUB immediately. Uses XST_mNO
.
XSRETURN_NO;
XSRETURN_NV
Return a double from an XSUB immediately. Uses XST_mNV
.
void XSRETURN_NV(NV nv)
XSRETURN_PV
Return a copy of a string from an XSUB immediately. Uses XST_mPV
.
void XSRETURN_PV(char* str)
XSRETURN_UNDEF
Return &PL_sv_undef
from an XSUB immediately. Uses XST_mUNDEF
.
XSRETURN_UNDEF;
XSRETURN_UV
Return an integer from an XSUB immediately. Uses XST_mUV
.
void XSRETURN_UV(IV uv)
XSRETURN_YES
Return &PL_sv_yes
from an XSUB immediately. Uses XST_mYES
.
XSRETURN_YES;
XST_mIV
Place an integer into the specified position pos
on the stack. The value is stored in a new mortal SV.
void XST_mIV(int pos, IV iv)
XST_mNO
Place &PL_sv_no
into the specified position pos
on the stack.
void XST_mNO(int pos)
XST_mNV
Place a double into the specified position pos
on the stack. The value is stored in a new mortal SV.
void XST_mNV(int pos, NV nv)
XST_mPV
Place a copy of a string into the specified position pos
on the stack. The value is stored in a new mortal SV.
void XST_mPV(int pos, char* str)
XST_mUNDEF
Place &PL_sv_undef
into the specified position pos
on the stack.
void XST_mUNDEF(int pos)
XST_mUV
Place an unsigned integer into the specified position pos
on the stack. The value is stored in a new mortal SV.
void XST_mUV(int pos, UV uv)
XST_mYES
Place &PL_sv_yes
into the specified position pos
on the stack.
void XST_mYES(int pos)
XS_VERSION
The version identifier for an XS module. This is usually handled automatically by ExtUtils::MakeMaker
. See "XS_VERSION_BOOTCHECK"
.
XS_VERSION_BOOTCHECK
Macro to verify that a PM module's $VERSION
variable matches the XS module's XS_VERSION
variable. This is usually handled automatically by xsubpp
. See "The VERSIONCHECK: Keyword" in perlxs.
XS_VERSION_BOOTCHECK;
See also "Unicode Support"
.
CAT2
This macro concatenates 2 tokens together.
token CAT2(token x, token y)
Copy
CopyD
The XSUB-writer's interface to the C memcpy
function. The src
is the source, dest
is the destination, nitems
is the number of items, and type
is the type. May fail on overlapping copies. See also "Move"
.
CopyD
is like Copy
but returns dest
. Useful for encouraging compilers to tail-call optimise.
void Copy (void* src, void* dest, int nitems, type)
void * CopyD(void* src, void* dest, int nitems, type)
delimcpy
Copy a source buffer to a destination buffer, stopping at (but not including) the first occurrence in the source of an unescaped (defined below) delimiter byte, delim
. The source is the bytes between from
and from_end
- 1. Similarly, the dest is to
up to to_end
.
The number of bytes copied is written to *retlen
.
Returns the position of the first uncopied delim
in the from
buffer, but if there is no such occurrence before from_end
, then from_end
is returned, and the entire buffer from
.. from_end
- 1 is copied.
If there is room in the destination available after the copy, an extra terminating safety NUL
byte is appended (not included in the returned length).
The error case is if the destination buffer is not large enough to accommodate everything that should be copied. In this situation, a value larger than to_end
- to
is written to *retlen
, and as much of the source as fits will be written to the destination. Not having room for the safety NUL
is not considered an error.
In the following examples, let x
be the delimiter, and 0
represent a NUL
byte (NOT the digit 0
). Then we would have
Source Destination
abcxdef abc0
provided the destination buffer is at least 4 bytes long.
An escaped delimiter is one which is immediately preceded by a single backslash. Escaped delimiters are copied, and the copy continues past the delimiter; the backslash is not copied:
Source Destination
abc\xdef abcxdef0
(provided the destination buffer is at least 8 bytes long).
It's actually somewhat more complicated than that. A sequence of any odd number of backslashes escapes the following delimiter, and the copy continues with exactly one of the backslashes stripped.
Source Destination
abc\xdef abcxdef0
abc\\\xdef abc\\xdef0
abc\\\\\xdef abc\\\\xdef0
(as always, if the destination is large enough)
An even number of preceding backslashes does not escape the delimiter, so that the copy stops just before it, and includes all the backslashes (no stripping; zero is considered even):
Source Destination
abcxdef abc0
abc\\xdef abc\\0
abc\\\\xdef abc\\\\0
char * delimcpy(char *to, const char *to_end, const char *from,
const char *from_end, const int delim,
I32 *retlen)
do_join
This performs a Perl join
, placing the joined output into sv
.
The elements to join are in SVs, stored in a C array of pointers to SVs, from **mark
to **sp - 1
. Hence *mark
is a reference to the first SV. Each SV will be coerced into a PV if not one already.
delim
contains the string (or coerced into a string) that is to separate each of the joined elements.
If any component is in UTF-8, the result will be as well, and all non-UTF-8 components will be converted to UTF-8 as necessary.
Magic and tainting are handled.
void do_join(SV *sv, SV *delim, SV **mark, SV **sp)
do_sprintf
This performs a Perl sprintf
placing the string output into sv
.
The elements to format are in SVs, stored in a C array of pointers to SVs of length len
> and beginning at **sarg
. The element referenced by *sarg
is the format.
Magic and tainting are handled.
void do_sprintf(SV *sv, SSize_t len, SV **sarg)
fbm_compile
Analyzes the string in order to make fast searches on it using fbm_instr()
-- the Boyer-Moore algorithm.
void fbm_compile(SV *sv, U32 flags)
fbm_instr
Returns the location of the SV in the string delimited by big
and bigend
(bigend
) is the char following the last char). It returns NULL
if the string can't be found. The sv
does not have to be fbm_compiled
, but the search will not be as fast then.
char * fbm_instr(unsigned char *big, unsigned char *bigend,
SV *littlestr, U32 flags)
foldEQ
Returns true if the leading len
bytes of the strings s1
and s2
are the same case-insensitively; false otherwise. Uppercase and lowercase ASCII range bytes match themselves and their opposite case counterparts. Non-cased and non-ASCII range bytes match only themselves.
I32 foldEQ(const char *a, const char *b, I32 len)
ibcmp
This is a synonym for (! foldEQ())
I32 ibcmp(const char *a, const char *b, I32 len)
ibcmp_locale
This is a synonym for (! foldEQ_locale())
I32 ibcmp_locale(const char *a, const char *b, I32 len)
ibcmp_utf8
This is a synonym for (! foldEQ_utf8())
I32 ibcmp_utf8(const char *s1, char **pe1, UV l1, bool u1,
const char *s2, char **pe2, UV l2, bool u2)
instr
Same as strstr(3), which finds and returns a pointer to the first occurrence of the NUL-terminated substring little
in the NUL-terminated string big
, returning NULL if not found. The terminating NUL bytes are not compared.
char * instr(const char *big, const char *little)
memCHRs
Returns the position of the first occurrence of the byte c
in the literal string "list"
, or NULL if c
doesn't appear in "list"
. All bytes are treated as unsigned char. Thus this macro can be used to determine if c
is in a set of particular characters. Unlike strchr(3), it works even if c
is NUL
(and the set doesn't include NUL
).
bool memCHRs("list", char c)
memEQ
Test two buffers (which may contain embedded NUL
characters, to see if they are equal. The len
parameter indicates the number of bytes to compare. Returns true or false. It is undefined behavior if either of the buffers doesn't contain at least len
bytes.
bool memEQ(char* s1, char* s2, STRLEN len)
memEQs
Like "memEQ", but the second string is a literal enclosed in double quotes, l1
gives the number of bytes in s1
. Returns true or false.
bool memEQs(char* s1, STRLEN l1, "s2")
memNE
Test two buffers (which may contain embedded NUL
characters, to see if they are not equal. The len
parameter indicates the number of bytes to compare. Returns true or false. It is undefined behavior if either of the buffers doesn't contain at least len
bytes.
bool memNE(char* s1, char* s2, STRLEN len)
memNEs
Like "memNE", but the second string is a literal enclosed in double quotes, l1
gives the number of bytes in s1
. Returns true or false.
bool memNEs(char* s1, STRLEN l1, "s2")
Move
MoveD
The XSUB-writer's interface to the C memmove
function. The src
is the source, dest
is the destination, nitems
is the number of items, and type
is the type. Can do overlapping moves. See also "Copy"
.
MoveD
is like Move
but returns dest
. Useful for encouraging compilers to tail-call optimise.
void Move (void* src, void* dest, int nitems, type)
void * MoveD(void* src, void* dest, int nitems, type)
my_snprintf
The C library snprintf
functionality, if available and standards-compliant (uses vsnprintf
, actually). However, if the vsnprintf
is not available, will unfortunately use the unsafe vsprintf
which can overrun the buffer (there is an overrun check, but that may be too late). Consider using sv_vcatpvf
instead, or getting vsnprintf
.
int my_snprintf(char *buffer, const Size_t len,
const char *format, ...)
my_sprintf
DEPRECATED!
It is planned to remove my_sprintf
from a future release of Perl. Do not use it for new code; remove it from existing code.
Do NOT use this due to the possibility of overflowing buffer
. Instead use my_snprintf()
int my_sprintf(NN char *buffer, NN const char *pat, ...)
my_strnlen
The C library strnlen
if available, or a Perl implementation of it.
my_strnlen()
computes the length of the string, up to maxlen
bytes. It will never attempt to address more than maxlen
bytes, making it suitable for use with strings that are not guaranteed to be NUL-terminated.
Size_t my_strnlen(const char *str, Size_t maxlen)
my_vsnprintf
The C library vsnprintf
if available and standards-compliant. However, if the vsnprintf
is not available, will unfortunately use the unsafe vsprintf
which can overrun the buffer (there is an overrun check, but that may be too late). Consider using sv_vcatpvf
instead, or getting vsnprintf
.
int my_vsnprintf(char *buffer, const Size_t len,
const char *format, va_list ap)
NewCopy
Combines Newx() and Copy() into a single macro. Dest will be allocated using Newx() and then src will be copied into it.
void NewCopy(void* src, void* dest, int nitems, type)
ninstr
Find the first (leftmost) occurrence of a sequence of bytes within another sequence. This is the Perl version of strstr()
, extended to handle arbitrary sequences, potentially containing embedded NUL
characters (NUL
is what the initial n
in the function name stands for; some systems have an equivalent, memmem()
, but with a somewhat different API).
Another way of thinking about this function is finding a needle in a haystack. big
points to the first byte in the haystack. big_end
points to one byte beyond the final byte in the haystack. little
points to the first byte in the needle. little_end
points to one byte beyond the final byte in the needle. All the parameters must be non-NULL
.
The function returns NULL
if there is no occurrence of little
within big
. If little
is the empty string, big
is returned.
Because this function operates at the byte level, and because of the inherent characteristics of UTF-8 (or UTF-EBCDIC), it will work properly if both the needle and the haystack are strings with the same UTF-8ness, but not if the UTF-8ness differs.
char * ninstr(const char *big, const char *bigend,
const char *little, const char *lend)
Nullch
Null character pointer. (No longer available when PERL_CORE
is defined.)
PL_na
A scratch pad variable in which to store a STRLEN
value. If would have been better named something like PL_temp_strlen
.
It is is typically used with SvPV
when one is actually planning to discard the returned length, (hence the length is "Not Applicable", which is how this variable got its name).
BUT BEWARE, if this is used in a situation where something that is using it is in a call stack with something else that is using it, this variable would get zapped, leading to hard-to-diagnose errors.
It is usually more efficient to either declare a local variable and use that instead, or to use the SvPV_nolen
macro.
STRLEN PL_na
rninstr
Like "ninstr"
, but instead finds the final (rightmost) occurrence of a sequence of bytes within another sequence, returning NULL
if there is no such occurrence.
char * rninstr(const char *big, const char *bigend,
const char *little, const char *lend)
savepv
Perl's version of strdup()
. Returns a pointer to a newly allocated string which is a duplicate of pv
. The size of the string is determined by strlen()
, which means it may not contain embedded NUL
characters and must have a trailing NUL
. To prevent memory leaks, the memory allocated for the new string needs to be freed when no longer needed. This can be done with the "Safefree"
function, or SAVEFREEPV
.
On some platforms, Windows for example, all allocated memory owned by a thread is deallocated when that thread ends. So if you need that not to happen, you need to use the shared memory functions, such as "savesharedpv"
.
char * savepv(const char *pv)
savepvn
Perl's version of what strndup()
would be if it existed. Returns a pointer to a newly allocated string which is a duplicate of the first len
bytes from pv
, plus a trailing NUL
byte. The memory allocated for the new string can be freed with the Safefree()
function.
On some platforms, Windows for example, all allocated memory owned by a thread is deallocated when that thread ends. So if you need that not to happen, you need to use the shared memory functions, such as "savesharedpvn"
.
char * savepvn(const char *pv, Size_t len)
savepvs
Like savepvn
, but takes a literal string instead of a string/length pair.
char* savepvs("literal string")
A version of savepv()
which allocates the duplicate string in memory which is shared between threads.
char * savesharedpv(const char *pv)
A version of savepvn()
which allocates the duplicate string in memory which is shared between threads. (With the specific difference that a NULL
pointer is not acceptable)
char * savesharedpvn(const char * const pv, const STRLEN len)
A version of savepvs()
which allocates the duplicate string in memory which is shared between threads.
char* savesharedpvs("literal string")
A version of savesharedpv()
which allocates the duplicate string in memory which is shared between threads.
char * savesharedsvpv(SV *sv)
savesvpv
A version of savepv()
/savepvn()
which gets the string to duplicate from the passed in SV using SvPV()
On some platforms, Windows for example, all allocated memory owned by a thread is deallocated when that thread ends. So if you need that not to happen, you need to use the shared memory functions, such as "savesharedsvpv"
.
char * savesvpv(SV *sv)
strEQ
Test two NUL
-terminated strings to see if they are equal. Returns true or false.
bool strEQ(char* s1, char* s2)
strGE
Test two NUL
-terminated strings to see if the first, s1
, is greater than or equal to the second, s2
. Returns true or false.
bool strGE(char* s1, char* s2)
strGT
Test two NUL
-terminated strings to see if the first, s1
, is greater than the second, s2
. Returns true or false.
bool strGT(char* s1, char* s2)
STRINGIFY
This macro surrounds its token with double quotes.
string STRINGIFY(token x)
strLE
Test two NUL
-terminated strings to see if the first, s1
, is less than or equal to the second, s2
. Returns true or false.
bool strLE(char* s1, char* s2)
strLT
Test two NUL
-terminated strings to see if the first, s1
, is less than the second, s2
. Returns true or false.
bool strLT(char* s1, char* s2)
strNE
Test two NUL
-terminated strings to see if they are different. Returns true or false.
bool strNE(char* s1, char* s2)
strnEQ
Test two NUL
-terminated strings to see if they are equal. The len
parameter indicates the number of bytes to compare. Returns true or false. (A wrapper for strncmp
).
bool strnEQ(char* s1, char* s2, STRLEN len)
strnNE
Test two NUL
-terminated strings to see if they are different. The len
parameter indicates the number of bytes to compare. Returns true or false. (A wrapper for strncmp
).
bool strnNE(char* s1, char* s2, STRLEN len)
STR_WITH_LEN
Returns two comma separated tokens of the input literal string, and its length. This is convenience macro which helps out in some API calls. Note that it can't be used as an argument to macros or functions that under some configurations might be macros, which means that it requires the full Perl_xxx(aTHX_ ...) form for any API calls where it's used.
pair STR_WITH_LEN("literal string")
Zero
ZeroD
The XSUB-writer's interface to the C memzero
function. The dest
is the destination, nitems
is the number of items, and type
is the type.
ZeroD
is like Zero
but returns dest
. Useful for encouraging compilers to tail-call optimise.
void Zero (void* dest, int nitems, type)
void * ZeroD(void* dest, int nitems, type)
SVt_PVOBJ
NOTE: SVt_PVOBJ
is experimental and may change or be removed without notice.
Type flag for object instances. See "svtype".
svtype
An enum of flags for Perl types. These are found in the file sv.h in the svtype
enum. Test these flags with the SvTYPE
macro.
The types are:
SVt_NULL
SVt_IV
SVt_NV
SVt_RV
SVt_PV
SVt_PVIV
SVt_PVNV
SVt_PVMG
SVt_INVLIST
SVt_REGEXP
SVt_PVGV
SVt_PVLV
SVt_PVAV
SVt_PVHV
SVt_PVCV
SVt_PVFM
SVt_PVIO
SVt_PVOBJ
These are most easily explained from the bottom up.
SVt_PVOBJ
is for object instances of the new `use feature 'class'` kind. SVt_PVIO
is for I/O objects, SVt_PVFM
for formats, SVt_PVCV
for subroutines, SVt_PVHV
for hashes and SVt_PVAV
for arrays.
All the others are scalar types, that is, things that can be bound to a $
variable. For these, the internal types are mostly orthogonal to types in the Perl language.
Hence, checking SvTYPE(sv) < SVt_PVAV
is the best way to see whether something is a scalar.
SVt_PVGV
represents a typeglob. If !SvFAKE(sv)
, then it is a real, incoercible typeglob. If SvFAKE(sv)
, then it is a scalar to which a typeglob has been assigned. Assigning to it again will stop it from being a typeglob. SVt_PVLV
represents a scalar that delegates to another scalar behind the scenes. It is used, e.g., for the return value of substr
and for tied hash and array elements. It can hold any scalar value, including a typeglob. SVt_REGEXP
is for regular expressions. SVt_INVLIST
is for Perl core internal use only.
SVt_PVMG
represents a "normal" scalar (not a typeglob, regular expression, or delegate). Since most scalars do not need all the internal fields of a PVMG, we save memory by allocating smaller structs when possible. All the other types are just simpler forms of SVt_PVMG
, with fewer internal fields. SVt_NULL
can only hold undef. SVt_IV
can hold undef, an integer, or a reference. (SVt_RV
is an alias for SVt_IV
, which exists for backward compatibility.) SVt_NV
can hold undef or a double. (In builds that support headless NVs, these could also hold a reference via a suitable offset, in the same way that SVt_IV does, but this is not currently supported and seems to be a rare use case.) SVt_PV
can hold undef
, a string, or a reference. SVt_PVIV
is a superset of SVt_PV
and SVt_IV
. SVt_PVNV
is a superset of SVt_PV
and SVt_NV
. SVt_PVMG
can hold anything SVt_PVNV
can hold, but it may also be blessed or magical.
AV_FROM_REF
CV_FROM_REF
HV_FROM_REF
The *V_FROM_REF
macros extract the SvRV()
from a given reference SV and return a suitably-cast to pointer to the referenced SV. When running under -DDEBUGGING
, assertions are also applied that check that ref is definitely a reference SV that refers to an SV of the right type.
AV * AV_FROM_REF(SV * ref)
CV * CV_FROM_REF(SV * ref)
HV * HV_FROM_REF(SV * ref)
BOOL_INTERNALS_sv_isbool
Checks if a SvBoolFlagsOK()
sv is a bool. Note that it is the caller's responsibility to ensure that the sv is SvBoolFlagsOK()
before calling this. This is only useful in specialized logic like serialization code where performance is critical and the flags have already been checked to be correct. Almost always you should be using sv_isbool(sv)
instead.
bool BOOL_INTERNALS_sv_isbool(SV* sv)
BOOL_INTERNALS_sv_isbool_false
Checks if a SvBoolFlagsOK()
sv is a false bool. Note that it is the caller's responsibility to ensure that the sv is SvBoolFlagsOK()
before calling this. This is only useful in specialized logic like serialization code where performance is critical and the flags have already been checked to be correct. This is NOT what you should use to check if an SV is "false", for that you should be using !SvTRUE(sv)
instead.
bool BOOL_INTERNALS_sv_isbool_false(SV* sv)
BOOL_INTERNALS_sv_isbool_true
Checks if a SvBoolFlagsOK()
sv is a true bool. Note that it is the caller's responsibility to ensure that the sv is SvBoolFlagsOK()
before calling this. This is only useful in specialized logic like serialization code where performance is critical and the flags have already been checked to be correct. This is NOT what you should use to check if an SV is "true", for that you should be using SvTRUE(sv)
instead.
bool BOOL_INTERNALS_sv_isbool_true(SV* sv)
boolSV
Returns a true SV if b
is a true value, or a false SV if b
is 0.
See also "PL_sv_yes"
and "PL_sv_no"
.
SV * boolSV(bool b)
croak_xs_usage
A specialised variant of croak()
for emitting the usage message for xsubs
croak_xs_usage(cv, "eee_yow");
works out the package name and subroutine name from cv
, and then calls croak()
. Hence if cv
is &ouch::awk
, it would call croak
as:
diag_listed_as: SKIPME
Perl_croak(aTHX_ "Usage: %" SVf "::%" SVf "(%s)", "ouch" "awk",
"eee_yow");
void croak_xs_usage(const CV * const cv,
const char * const params)
DEFSV
Returns the SV associated with $_
SV * DEFSV
DEFSV_set
Associate sv
with $_
void DEFSV_set(SV * sv)
get_sv
Returns the SV of the specified Perl scalar. flags
are passed to "gv_fetchpv
". If GV_ADD
is set and the Perl variable does not exist then it will be created. If flags
is zero and the variable does not exist then NULL is returned.
NOTE: the perl_get_sv()
form is deprecated.
SV * get_sv(const char *name, I32 flags)
isGV_with_GP
Returns a boolean as to whether or not sv
is a GV with a pointer to a GP (glob pointer).
bool isGV_with_GP(SV * sv)
looks_like_number
Test if the content of an SV looks like a number (or is a number). Inf
and Infinity
are treated as numbers (so will not issue a non-numeric warning), even if your atof()
doesn't grok them. Get-magic is ignored.
I32 looks_like_number(SV * const sv)
MUTABLE_AV
MUTABLE_CV
MUTABLE_GV
MUTABLE_HV
MUTABLE_IO
MUTABLE_PTR
MUTABLE_SV
The MUTABLE_*
() macros cast pointers to the types shown, in such a way (compiler permitting) that casting away const-ness will give a warning; e.g.:
const SV *sv = ...;
AV *av1 = (AV*)sv; <== BAD: the const has been silently
cast away
AV *av2 = MUTABLE_AV(sv); <== GOOD: it may warn
MUTABLE_PTR
is the base macro used to derive new casts. The other already-built-in ones return pointers to what their names indicate.
AV * MUTABLE_AV (AV * p)
CV * MUTABLE_CV (CV * p)
GV * MUTABLE_GV (GV * p)
HV * MUTABLE_HV (HV * p)
IO * MUTABLE_IO (IO * p)
void * MUTABLE_PTR(void * p)
SV * MUTABLE_SV (SV * p)
newRV
newRV_inc
These are identical. They create an RV wrapper for an SV. The reference count for the original SV is incremented.
SV * newRV(SV * const sv)
newRV_noinc
Creates an RV wrapper for an SV. The reference count for the original SV is not incremented.
SV * newRV_noinc(SV * const tmpRef)
newSV
Creates a new SV. A non-zero len
parameter indicates the number of bytes of preallocated string space the SV should have. An extra byte for a trailing NUL
is also reserved. (SvPOK
is not set for the SV even if string space is allocated.) The reference count for the new SV is set to 1.
In 5.9.3, newSV()
replaces the older NEWSV()
API, and drops the first parameter, x, a debug aid which allowed callers to identify themselves. This aid has been superseded by a new build option, PERL_MEM_LOG
(see "PERL_MEM_LOG" in perlhacktips). The older API is still there for use in XS modules supporting older perls.
SV * newSV(const STRLEN len)
newSVbool
Creates a new SV boolean.
SV * newSVbool(const bool bool_val)
newSV_false
Creates a new SV that is a boolean false.
SV * newSV_false()
newSVhek
Creates a new SV from the hash key structure. It will generate scalars that point to the shared string table where possible. Returns a new (undefined) SV if hek
is NULL.
SV * newSVhek(const HEK * const hek)
newSVhek_mortal
Creates a new mortal SV from the hash key structure. It will generate scalars that point to the shared string table where possible. Returns a new (undefined) SV if hek
is NULL.
This is more efficient than using sv_2mortal(newSVhek( ... ))
SV * newSVhek_mortal(const HEK * const hek)
newSViv
Creates a new SV and copies an integer into it. The reference count for the SV is set to 1.
SV * newSViv(const IV i)
newSVnv
Creates a new SV and copies a floating point value into it. The reference count for the SV is set to 1.
SV * newSVnv(const NV n)
newSVpadname
NOTE: newSVpadname
is experimental and may change or be removed without notice.
Creates a new SV containing the pad name.
SV* newSVpadname(PADNAME *pn)
newSVpv
Creates a new SV and copies a string (which may contain NUL
(\0
) characters) into it. The reference count for the SV is set to 1. If len
is zero, Perl will compute the length using strlen()
, (which means if you use this option, that s
can't have embedded NUL
characters and has to have a terminating NUL
byte).
This function can cause reliability issues if you are likely to pass in empty strings that are not null terminated, because it will run strlen on the string and potentially run past valid memory.
Using "newSVpvn" is a safer alternative for non NUL
terminated strings. For string literals use "newSVpvs" instead. This function will work fine for NUL
terminated strings, but if you want to avoid the if statement on whether to call strlen
use newSVpvn
instead (calling strlen
yourself).
SV * newSVpv(const char * const s, const STRLEN len)
newSVpvf
Creates a new SV and initializes it with the string formatted like sv_catpvf
.
NOTE: newSVpvf
must be explicitly called as Perl_newSVpvf
with an aTHX_
parameter.
SV * Perl_newSVpvf(pTHX_ const char * const pat, ...)
newSVpvf_nocontext
Like "newSVpvf"
but does not take a thread context (aTHX
) parameter, so is used in situations where the caller doesn't already have the thread context.
SV * newSVpvf_nocontext(const char * const pat, ...)
newSVpvn
Creates a new SV and copies a string into it, which may contain NUL
characters (\0
) and other binary data. The reference count for the SV is set to 1. Note that if len
is zero, Perl will create a zero length (Perl) string. You are responsible for ensuring that the source buffer is at least len
bytes long. If the buffer
argument is NULL the new SV will be undefined.
SV * newSVpvn(const char * const buffer, const STRLEN len)
newSVpvn_flags
Creates a new SV and copies a string (which may contain NUL
(\0
) characters) into it. The reference count for the SV is set to 1. Note that if len
is zero, Perl will create a zero length string. You are responsible for ensuring that the source string is at least len
bytes long. If the s
argument is NULL the new SV will be undefined. Currently the only flag bits accepted are SVf_UTF8
and SVs_TEMP
. If SVs_TEMP
is set, then sv_2mortal()
is called on the result before returning. If SVf_UTF8
is set, s
is considered to be in UTF-8 and the SVf_UTF8
flag will be set on the new SV. newSVpvn_utf8()
is a convenience wrapper for this function, defined as
#define newSVpvn_utf8(s, len, u) \
newSVpvn_flags((s), (len), (u) ? SVf_UTF8 : 0)
SV * newSVpvn_flags(const char * const s, const STRLEN len,
const U32 flags)
Creates a new SV with its SvPVX_const
pointing to a shared string in the string table. If the string does not already exist in the table, it is created first. Turns on the SvIsCOW
flag (or READONLY
and FAKE
in 5.16 and earlier). If the hash
parameter is non-zero, that value is used; otherwise the hash is computed. The string's hash can later be retrieved from the SV with the "SvSHARED_HASH"
macro. The idea here is that as the string table is used for shared hash keys these strings will have SvPVX_const == HeKEY
and hash lookup will avoid string compare.
SV * newSVpvn_share(const char *s, I32 len, U32 hash)
newSVpvn_utf8
Creates a new SV and copies a string (which may contain NUL
(\0
) characters) into it. If utf8
is true, calls SvUTF8_on
on the new SV. Implemented as a wrapper around newSVpvn_flags
.
SV* newSVpvn_utf8(const char* s, STRLEN len, U32 utf8)
newSVpvs
Like newSVpvn
, but takes a literal string instead of a string/length pair.
SV* newSVpvs("literal string")
newSVpvs_flags
Like newSVpvn_flags
, but takes a literal string instead of a string/length pair.
SV* newSVpvs_flags("literal string", U32 flags)
Like newSVpvn_share
, but takes a NUL
-terminated string instead of a string/length pair.
SV * newSVpv_share(const char *s, U32 hash)
Like newSVpvn_share
, but takes a literal string instead of a string/length pair and omits the hash parameter.
SV* newSVpvs_share("literal string")
newSVrv
Creates a new SV for the existing RV, rv
, to point to. If rv
is not an RV then it will be upgraded to one. If classname
is non-null then the new SV will be blessed in the specified package. The new SV is returned and its reference count is 1. The reference count 1 is owned by rv
. See also newRV_inc() and newRV_noinc() for creating a new RV properly.
SV * newSVrv(SV * const rv, const char * const classname)
newSVsv
newSVsv_flags
newSVsv_nomg
These create a new SV which is an exact duplicate of the original SV (using sv_setsv
.)
They differ only in that newSVsv
performs 'get' magic; newSVsv_nomg
skips any magic; and newSVsv_flags
allows you to explicitly set a flags
parameter.
SV * newSVsv (SV * const old)
SV * newSVsv_flags(SV * const old, I32 flags)
SV * newSVsv_nomg (SV * const old)
newSV_true
Creates a new SV that is a boolean true.
SV * newSV_true()
newSV_type
Creates a new SV, of the type specified. The reference count for the new SV is set to 1.
SV * newSV_type(const svtype type)
newSV_type_mortal
Creates a new mortal SV, of the type specified. The reference count for the new SV is set to 1.
This is equivalent to SV* sv = sv_2mortal(newSV_type(<some type>)) and SV* sv = sv_newmortal(); sv_upgrade(sv, <some_type>) but should be more efficient than both of them. (Unless sv_2mortal is inlined at some point in the future.)
SV * newSV_type_mortal(const svtype type)
newSVuv
Creates a new SV and copies an unsigned integer into it. The reference count for the SV is set to 1.
SV * newSVuv(const UV u)
Nullsv
Null SV pointer. (No longer available when PERL_CORE
is defined.)
PL_sv_no
This is the false
SV. It is readonly. See "PL_sv_yes"
. Always refer to this as &PL_sv_no
.
SV PL_sv_no
PL_sv_undef
This is the undef
SV. It is readonly. Always refer to this as &PL_sv_undef
.
SV PL_sv_undef
PL_sv_yes
This is the true
SV. It is readonly. See "PL_sv_no"
. Always refer to this as &PL_sv_yes
.
SV PL_sv_yes
PL_sv_zero
This readonly SV has a zero numeric value and a "0"
string value. It's similar to "PL_sv_no"
except for its string value. Can be used as a cheap alternative to mXPUSHi(0)
for example. Always refer to this as &PL_sv_zero
. Introduced in 5.28.
SV PL_sv_zero
SAVE_DEFSV
Localize $_
. See "Localizing changes" in perlguts.
void SAVE_DEFSV
sortsv
In-place sort an array of SV pointers with the given comparison routine.
Currently this always uses mergesort. See "sortsv_flags"
for a more flexible routine.
void sortsv(SV **array, size_t num_elts, SVCOMPARE_t cmp)
sortsv_flags
In-place sort an array of SV pointers with the given comparison routine, with various SORTf_* flag options.
void sortsv_flags(SV **array, size_t num_elts, SVCOMPARE_t cmp,
U32 flags)
SvAMAGIC
Returns a boolean as to whether sv
has overloading (active magic) enabled or not.
bool SvAMAGIC(SV * sv)
SvAMAGIC_off
Indicate that sv
has overloading (active magic) disabled.
void SvAMAGIC_off(SV *sv)
SvAMAGIC_on
Indicate that sv
has overloading (active magic) enabled.
void SvAMAGIC_on(SV *sv)
sv_backoff
Remove any string offset. You should normally use the SvOOK_off
macro wrapper instead.
void sv_backoff(SV * const sv)
sv_bless
Blesses an SV into a specified package. The SV must be an RV. The package must be designated by its stash (see "gv_stashpv"
). The reference count of the SV is unaffected.
SV * sv_bless(SV * const sv, HV * const stash)
SvBoolFlagsOK
Returns a bool indicating whether the SV has the right flags set such that it is safe to call BOOL_INTERNALS_sv_isbool()
or BOOL_INTERNALS_sv_isbool_true()
or BOOL_INTERNALS_sv_isbool_false()
. Currently equivalent to SvIandPOK(sv)
or SvIOK(sv) && SvPOK(sv)
. Serialization may want to unroll this check. If so you are strongly recommended to add code like assert(SvBoolFlagsOK(sv));
before calling using any of the BOOL_INTERNALS macros.
U32 SvBoolFlagsOK(SV* sv)
sv_catpv
sv_catpv_flags
sv_catpv_mg
sv_catpv_nomg
These concatenate the NUL
-terminated string sstr
onto the end of the string which is in the SV. If the SV has the UTF-8 status set, then the bytes appended should be valid UTF-8.
They differ only in how they handle magic:
sv_catpv_mg
performs both 'get' and 'set' magic.
sv_catpv
performs only 'get' magic.
sv_catpv_nomg
skips all magic.
sv_catpv_flags
has an extra flags
parameter which allows you to specify any combination of magic handling (using SV_GMAGIC
and/or SV_SMAGIC
), and to also override the UTF-8 handling. By supplying the SV_CATUTF8
flag, the appended string is forced to be interpreted as UTF-8; by supplying instead the SV_CATBYTES
flag, it will be interpreted as just bytes. Either the SV or the string appended will be upgraded to UTF-8 if necessary.
void sv_catpv (SV * const dsv, const char *sstr)
void sv_catpv_flags(SV *dsv, const char *sstr, const I32 flags)
void sv_catpv_mg (SV * const dsv, const char * const sstr)
void sv_catpv_nomg (SV * const dsv, const char *sstr)
sv_catpvf
sv_catpvf_mg
sv_catpvf_mg_nocontext
sv_catpvf_nocontext
These process their arguments like sprintf
, and append the formatted output to an SV. As with sv_vcatpvfn
, argument reordering is not supporte when called with a non-null C-style variable argument list.
If the appended data contains "wide" characters (including, but not limited to, SVs with a UTF-8 PV formatted with %s
, and characters >255 formatted with %c
), the original SV might get upgraded to UTF-8.
If the original SV was UTF-8, the pattern should be valid UTF-8; if the original SV was bytes, the pattern should be too.
All perform 'get' magic, but only sv_catpvf_mg
and sv_catpvf_mg_nocontext
perform 'set' magic.
sv_catpvf_nocontext
and sv_catpvf_mg_nocontext
do not take a thread context (aTHX
) parameter, so are used in situations where the caller doesn't already have the thread context.
NOTE: sv_catpvf
must be explicitly called as Perl_sv_catpvf
with an aTHX_
parameter.
NOTE: sv_catpvf_mg
must be explicitly called as Perl_sv_catpvf_mg
with an aTHX_
parameter.
void Perl_sv_catpvf (pTHX_ SV * const sv,
const char * const pat, ...)
void Perl_sv_catpvf_mg (pTHX_ SV * const sv,
const char * const pat, ...)
void sv_catpvf_mg_nocontext(SV * const sv,
const char * const pat, ...)
void sv_catpvf_nocontext (SV * const sv,
const char * const pat, ...)
sv_catpvn
sv_catpvn_flags
sv_catpvn_mg
sv_catpvn_nomg
These concatenate the len
bytes of the string beginning at ptr
onto the end of the string which is in dsv
. The caller must make sure ptr
contains at least len
bytes.
For all but sv_catpvn_flags
, the string appended is assumed to be valid UTF-8 if the SV has the UTF-8 status set, and a string of bytes otherwise.
They differ in that:
sv_catpvn_mg
performs both 'get' and 'set' magic on dsv
.
sv_catpvn
performs only 'get' magic.
sv_catpvn_nomg
skips all magic.
sv_catpvn_flags
has an extra flags
parameter which allows you to specify any combination of magic handling (using SV_GMAGIC
and/or SV_SMAGIC
) and to also override the UTF-8 handling. By supplying the SV_CATBYTES
flag, the appended string is interpreted as plain bytes; by supplying instead the SV_CATUTF8
flag, it will be interpreted as UTF-8, and the dsv
will be upgraded to UTF-8 if necessary.
sv_catpvn
, sv_catpvn_mg
, and sv_catpvn_nomg
are implemented in terms of sv_catpvn_flags
.
void sv_catpvn (SV *dsv, const char *sstr, STRLEN len)
void sv_catpvn_flags(SV * const dsv, const char *sstr,
const STRLEN len, const I32 flags)
void sv_catpvn_mg (SV *dsv, const char *sstr, STRLEN len)
void sv_catpvn_nomg (SV *dsv, const char *sstr, STRLEN len)
sv_catpvs
Like sv_catpvn
, but takes a literal string instead of a string/length pair.
void sv_catpvs(SV* sv, "literal string")
sv_catpvs_flags
Like sv_catpvn_flags
, but takes a literal string instead of a string/length pair.
void sv_catpvs_flags(SV* sv, "literal string", I32 flags)
sv_catpvs_mg
Like sv_catpvn_mg
, but takes a literal string instead of a string/length pair.
void sv_catpvs_mg(SV* sv, "literal string")
sv_catpvs_nomg
Like sv_catpvn_nomg
, but takes a literal string instead of a string/length pair.
void sv_catpvs_nomg(SV* sv, "literal string")
sv_catsv
sv_catsv_flags
sv_catsv_mg
sv_catsv_nomg
These concatenate the string from SV sstr
onto the end of the string in SV dsv
. If sstr
is null, these are no-ops; otherwise only dsv
is modified.
They differ only in what magic they perform:
sv_catsv_mg
performs 'get' magic on both SVs before the copy, and 'set' magic on dsv
afterwards.
sv_catsv
performs just 'get' magic, on both SVs.
sv_catsv_nomg
skips all magic.
sv_catsv_flags
has an extra flags
parameter which allows you to use SV_GMAGIC
and/or SV_SMAGIC
to specify any combination of magic handling (although either both or neither SV will have 'get' magic applied to it.)
sv_catsv
, sv_catsv_mg
, and sv_catsv_nomg
are implemented in terms of sv_catsv_flags
.
void sv_catsv (SV *dsv, SV *sstr)
void sv_catsv_flags(SV * const dsv, SV * const sstr,
const I32 flags)
void sv_catsv_mg (SV *dsv, SV *sstr)
void sv_catsv_nomg (SV *dsv, SV *sstr)
SV_CHECK_THINKFIRST
Remove any encumbrances from sv
, that need to be taken care of before it is modifiable. For example if it is Copy on Write (COW), now is the time to make that copy.
If you know that you are about to change the PV value of sv
, instead use "SV_CHECK_THINKFIRST_COW_DROP
" to avoid the write that would be immediately written again.
void SV_CHECK_THINKFIRST(SV * sv)
SV_CHECK_THINKFIRST_COW_DROP
Call this when you are about to replace the PV value in sv
, which is potentially copy-on-write. It stops any sharing with other SVs, so that no Copy on Write (COW) actually happens. This COW would be useless, as it would immediately get changed to something else. This function also removes any other encumbrances that would be problematic when changing sv
.
void SV_CHECK_THINKFIRST_COW_DROP(SV * sv)
sv_chop
Efficient removal of characters from the beginning of the string buffer. SvPOK(sv)
, or at least SvPOKp(sv)
, must be true and ptr
must be a pointer to somewhere inside the string buffer. ptr
becomes the first character of the adjusted string. Uses the OOK
hack. On return, only SvPOK(sv)
and SvPOKp(sv)
among the OK
flags will be true.
Beware: after this function returns, ptr
and SvPVX_const(sv) may no longer refer to the same chunk of data.
The unfortunate similarity of this function's name to that of Perl's chop
operator is strictly coincidental. This function works from the left; chop
works from the right.
void sv_chop(SV * const sv, const char * const ptr)
sv_clear
Clear an SV: call any destructors, free up any memory used by the body, and free the body itself. The SV's head is not freed, although its type is set to all 1's so that it won't inadvertently be assumed to be live during global destruction etc. This function should only be called when REFCNT
is zero. Most of the time you'll want to call SvREFCNT_dec
instead.
void sv_clear(SV * const orig_sv)
sv_cmp
Compares the strings in two SVs. Returns -1, 0, or 1 indicating whether the string in sv1
is less than, equal to, or greater than the string in sv2
. Is UTF-8 and 'use bytes'
aware, handles get magic, and will coerce its args to strings if necessary. See also "sv_cmp_locale"
.
I32 sv_cmp(SV * const sv1, SV * const sv2)
sv_cmp_flags
Compares the strings in two SVs. Returns -1, 0, or 1 indicating whether the string in sv1
is less than, equal to, or greater than the string in sv2
. Is UTF-8 and 'use bytes'
aware and will coerce its args to strings if necessary. If the flags has the SV_GMAGIC
bit set, it handles get magic. See also "sv_cmp_locale_flags"
.
I32 sv_cmp_flags(SV * const sv1, SV * const sv2, const U32 flags)
sv_cmp_locale
Compares the strings in two SVs in a locale-aware manner. Is UTF-8 and 'use bytes'
aware, handles get magic, and will coerce its args to strings if necessary. See also "sv_cmp"
.
I32 sv_cmp_locale(SV * const sv1, SV * const sv2)
sv_cmp_locale_flags
Compares the strings in two SVs in a locale-aware manner. Is UTF-8 and 'use bytes'
aware and will coerce its args to strings if necessary. If the flags contain SV_GMAGIC
, it handles get magic. See also "sv_cmp_flags"
.
I32 sv_cmp_locale_flags(SV * const sv1, SV * const sv2,
const U32 flags)
sv_collxfrm
This calls sv_collxfrm_flags
with the SV_GMAGIC flag. See "sv_collxfrm_flags"
.
char * sv_collxfrm(SV * const sv, STRLEN * const nxp)
sv_collxfrm_flags
Add Collate Transform magic to an SV if it doesn't already have it. If the flags contain SV_GMAGIC
, it handles get-magic.
Any scalar variable may carry PERL_MAGIC_collxfrm
magic that contains the scalar data of the variable, but transformed to such a format that a normal memory comparison can be used to compare the data according to the locale settings.
char * sv_collxfrm_flags(SV * const sv, STRLEN * const nxp,
I32 const flags)
sv_copypv
sv_copypv_flags
sv_copypv_nomg
These copy a stringified representation of the source SV into the destination SV. They automatically perform coercion of numeric values into strings. Guaranteed to preserve the UTF8
flag even from overloaded objects. Similar in nature to sv_2pv[_flags]
but they operate directly on an SV instead of just the string. Mostly they use "sv_2pv_flags
" to do the work, except when that would lose the UTF-8'ness of the PV.
The three forms differ only in whether or not they perform 'get magic' on sv
. sv_copypv_nomg
skips 'get magic'; sv_copypv
performs it; and sv_copypv_flags
either performs it (if the SV_GMAGIC
bit is set in flags
) or doesn't (if that bit is cleared).
void sv_copypv (SV * const dsv, SV * const ssv)
void sv_copypv_flags(SV * const dsv, SV * const ssv,
const I32 flags)
void sv_copypv_nomg (SV * const dsv, SV * const ssv)
SvCUR
Returns the length, in bytes, of the PV inside the SV. Note that this may not match Perl's length
; for that, use sv_len_utf8(sv)
. See "SvLEN"
also.
STRLEN SvCUR(SV* sv)
SvCUR_set
Sets the current length, in bytes, of the C string which is in the SV. See "SvCUR"
and SvIV_set
>.
void SvCUR_set(SV* sv, STRLEN len)
sv_2cv
Using various gambits, try to get a CV from an SV; in addition, try if possible to set *st
and *gvp
to the stash and GV associated with it. The flags in lref
are passed to gv_fetchsv
.
CV * sv_2cv(SV *sv, HV ** const st, GV ** const gvp,
const I32 lref)
sv_dec
sv_dec_nomg
These auto-decrement the value in the SV, doing string to numeric conversion if necessary. They both handle operator overloading.
They differ only in that:
sv_dec
handles 'get' magic; sv_dec_nomg
skips 'get' magic.
void sv_dec(SV * const sv)
sv_derived_from
Exactly like "sv_derived_from_pv", but doesn't take a flags
parameter.
bool sv_derived_from(SV *sv, const char * const name)
sv_derived_from_hv
Exactly like "sv_derived_from_pvn", but takes the name string as the HvNAME
of the given HV (which would presumably represent a stash).
bool sv_derived_from_hv(SV *sv, HV *hv)
sv_derived_from_pv
Exactly like "sv_derived_from_pvn", but takes a nul-terminated string instead of a string/length pair.
bool sv_derived_from_pv(SV *sv, const char * const name,
U32 flags)
sv_derived_from_pvn
Returns a boolean indicating whether the SV is derived from the specified class at the C level. To check derivation at the Perl level, call isa()
as a normal Perl method.
Currently, the only significant value for flags
is SVf_UTF8.
bool sv_derived_from_pvn(SV *sv, const char * const name,
const STRLEN len, U32 flags)
sv_derived_from_sv
Exactly like "sv_derived_from_pvn", but takes the name string in the form of an SV instead of a string/length pair. This is the advised form.
bool sv_derived_from_sv(SV *sv, SV *namesv, U32 flags)
sv_does
Like "sv_does_pv", but doesn't take a flags
parameter.
bool sv_does(SV *sv, const char * const name)
sv_does_pv
Like "sv_does_sv", but takes a nul-terminated string instead of an SV.
bool sv_does_pv(SV *sv, const char * const name, U32 flags)
sv_does_pvn
Like "sv_does_sv", but takes a string/length pair instead of an SV.
bool sv_does_pvn(SV *sv, const char * const name,
const STRLEN len, U32 flags)
sv_does_sv
Returns a boolean indicating whether the SV performs a specific, named role. The SV can be a Perl object or the name of a Perl class.
bool sv_does_sv(SV *sv, SV *namesv, U32 flags)
SvEND
Returns a pointer to the spot just after the last character in the string which is in the SV, where there is usually a trailing NUL
character (even though Perl scalars do not strictly require it). See "SvCUR"
. Access the character as *(SvEND(sv))
.
Warning: If SvCUR
is equal to SvLEN
, then SvEND
points to unallocated memory.
char* SvEND(SV* sv)
sv_eq
sv_eq_flags
These each return a boolean indicating whether or not the strings in the two SVs are equal. If 'use bytes'
is in effect, the comparison is byte-by-byte; otherwise character-by-character. Each will coerce its args to strings if necessary.
They differ only in that sv_eq
always processes get magic, while sv_eq_flags
processes get magic only when the flags
parameter has the SV_GMAGIC
bit set.
These functions do not handle operator overloading. For versions that do, see instead "sv_streq"
or "sv_streq_flags"
.
I32 sv_eq (SV *sv1, SV *sv2)
I32 sv_eq_flags(SV *sv1, SV *sv2, const U32 flags)
sv_force_normal
Undo various types of fakery on an SV: if the PV is a shared string, make a private copy; if we're a ref, stop refing; if we're a glob, downgrade to an xpvmg
. See also "sv_force_normal_flags"
.
void sv_force_normal(SV *sv)
sv_force_normal_flags
Undo various types of fakery on an SV, where fakery means "more than" a string: if the PV is a shared string, make a private copy; if we're a ref, stop refing; if we're a glob, downgrade to an xpvmg
; if we're a copy-on-write scalar, this is the on-write time when we do the copy, and is also used locally; if this is a vstring, drop the vstring magic. If SV_COW_DROP_PV
is set then a copy-on-write scalar drops its PV buffer (if any) and becomes SvPOK_off
rather than making a copy. (Used where this scalar is about to be set to some other value.) In addition, the flags
parameter gets passed to sv_unref_flags()
when unreffing. sv_force_normal
calls this function with flags set to 0.
This function is expected to be used to signal to perl that this SV is about to be written to, and any extra book-keeping needs to be taken care of. Hence, it croaks on read-only values.
void sv_force_normal_flags(SV * const sv, const U32 flags)
sv_free
Decrement an SV's reference count, and if it drops to zero, call sv_clear
to invoke destructors and free up any memory used by the body; finally, deallocating the SV's head itself. Normally called via a wrapper macro SvREFCNT_dec
.
void sv_free(SV * const sv)
SvGAMAGIC
Returns true if the SV has get magic or overloading. If either is true then the scalar is active data, and has the potential to return a new value every time it is accessed. Hence you must be careful to only read it once per user logical operation and work with that returned value. If neither is true then the scalar's value cannot change unless written to.
U32 SvGAMAGIC(SV* sv)
sv_get_backrefs
NOTE: sv_get_backrefs
is experimental and may change or be removed without notice.
If sv
is the target of a weak reference then it returns the back references structure associated with the sv; otherwise return NULL
.
When returning a non-null result the type of the return is relevant. If it is an AV then the elements of the AV are the weak reference RVs which point at this item. If it is any other type then the item itself is the weak reference.
See also Perl_sv_add_backref()
, Perl_sv_del_backref()
, Perl_sv_kill_backrefs()
SV * sv_get_backrefs(SV * const sv)
SvGETMAGIC
Invokes "mg_get"
on an SV if it has 'get' magic. For example, this will call FETCH
on a tied variable. As of 5.37.1, this function is guaranteed to evaluate its argument exactly once.
void SvGETMAGIC(SV *sv)
sv_gets
Get a line from the filehandle and store it into the SV, optionally appending to the currently-stored string. If append
is not 0, the line is appended to the SV instead of overwriting it. append
should be set to the byte offset that the appended string should start at in the SV (typically, SvCUR(sv)
is a suitable choice).
char * sv_gets(SV * const sv, PerlIO * const fp, I32 append)
SvGROW
Expands the character buffer in the SV so that it has room for the indicated number of bytes (remember to reserve space for an extra trailing NUL
character). Calls sv_grow
to perform the expansion if necessary. Returns a pointer to the character buffer. SV must be of type >= SVt_PV
. One alternative is to call sv_grow
if you are not sure of the type of SV.
You might mistakenly think that len
is the number of bytes to add to the existing size, but instead it is the total size sv
should be.
char * SvGROW(SV* sv, STRLEN len)
SvIandPOK
Returns a bool indicating whether the SV is both SvPOK()
and SvIOK()
at the same time. Equivalent to SvIOK(sv) && SvPOK(sv)
but more efficient.
U32 SvIandPOK(SV* sv)
SvIandPOK_off
Unsets the PV and IV status of an SV in one operation. Equivalent to SvIOK_off(sv); SvPK_off(v);
but more efficient.
void SvIandPOK_off(SV* sv)
SvIandPOK_on
Tells an SV that is a string and a number in one operation. Equivalent to SvIOK_on(sv); SvPOK_on(sv);
but more efficient.
void SvIandPOK_on(SV* sv)
sv_inc
sv_inc_nomg
These auto-increment the value in the SV, doing string to numeric conversion if necessary. They both handle operator overloading.
They differ only in that sv_inc
performs 'get' magic; sv_inc_nomg
skips any magic.
void sv_inc(SV * const sv)
sv_insert
sv_insert_flags
These insert and/or replace a string at the specified offset/length within the SV. Similar to the Perl substr()
function, with littlelen
bytes starting at little
replacing len
bytes of the string in bigstr
starting at offset
. They handle get magic.
sv_insert_flags
is identical to plain sv_insert
, but the extra flags
are passed to the SvPV_force_flags
operation that is internally applied to bigstr
.
void sv_insert (SV * const bigstr, const STRLEN offset,
const STRLEN len, const char * const little,
const STRLEN littlelen)
void sv_insert_flags(SV * const bigstr, const STRLEN offset,
const STRLEN len, const char *little,
const STRLEN littlelen, const U32 flags)
sv_2io
Using various gambits, try to get an IO from an SV: the IO slot if its a GV; or the recursive result if we're an RV; or the IO slot of the symbol named after the PV if we're a string.
'Get' magic is ignored on the sv
passed in, but will be called on SvRV(sv)
if sv
is an RV.
IO * sv_2io(SV * const sv)
SvIOK
Returns a U32 value indicating whether the SV contains an integer.
U32 SvIOK(SV* sv)
SvIOK_notUV
Returns a boolean indicating whether the SV contains a signed integer.
bool SvIOK_notUV(SV* sv)
SvIOK_off
Unsets the IV status of an SV.
void SvIOK_off(SV* sv)
SvIOK_on
Tells an SV that it is an integer.
void SvIOK_on(SV* sv)
SvIOK_only
Tells an SV that it is an integer and disables all other OK
bits.
void SvIOK_only(SV* sv)
SvIOK_only_UV
Tells an SV that it is an unsigned integer and disables all other OK
bits.
void SvIOK_only_UV(SV* sv)
SvIOKp
Returns a U32 value indicating whether the SV contains an integer. Checks the private setting. Use SvIOK
instead.
U32 SvIOKp(SV* sv)
SvIOK_UV
Returns a boolean indicating whether the SV contains an integer that must be interpreted as unsigned. A non-negative integer whose value is within the range of both an IV and a UV may be flagged as either SvUOK
or SvIOK
.
bool SvIOK_UV(SV* sv)
sv_isa
Returns a boolean indicating whether the SV is blessed into the specified class.
This does not check for subtypes or method overloading. Use sv_isa_sv
to verify an inheritance relationship in the same way as the isa
operator by respecting any isa()
method overloading; or sv_derived_from_sv
to test directly on the actual object type.
int sv_isa(SV *sv, const char * const name)
sv_isa_sv
Returns a boolean indicating whether the SV is an object reference and is derived from the specified class, respecting any isa()
method overloading it may have. Returns false if sv
is not a reference to an object, or is not derived from the specified class.
This is the function used to implement the behaviour of the isa
operator.
Does not invoke magic on sv
.
Not to be confused with the older sv_isa
function, which does not use an overloaded isa()
method, nor will check subclassing.
bool sv_isa_sv(SV *sv, SV *namesv)
SvIsBOOL
Returns true if the SV is one of the special boolean constants (PL_sv_yes or PL_sv_no), or is a regular SV whose last assignment stored a copy of one.
bool SvIsBOOL(SV* sv)
SvIsCOW
Returns a U32 value indicating whether the SV is Copy-On-Write (either shared hash key scalars, or full Copy On Write scalars if 5.9.0 is configured for COW).
U32 SvIsCOW(SV* sv)
Returns a boolean indicating whether the SV is Copy-On-Write shared hash key scalar.
bool SvIsCOW_shared_hash(SV* sv)
sv_isobject
Returns a boolean indicating whether the SV is an RV pointing to a blessed object. If the SV is not an RV, or if the object is not blessed, then this will return false.
int sv_isobject(SV *sv)
SvIV
SvIV_nomg
SvIVx
These each coerce the given SV to IV and return it. The returned value in many circumstances will get stored in sv
's IV slot, but not in all cases. (Use "sv_setiv"
to make sure it does).
As of 5.37.1, all are guaranteed to evaluate sv
only once.
SvIVx
is now identical to SvIV
, but prior to 5.37.1, it was the only form guaranteed to evaluate sv
only once.
SvIV_nomg
is the same as SvIV
, but does not perform 'get' magic.
IV SvIV(SV *sv)
sv_2iv_flags
Return the integer value of an SV, doing any necessary string conversion. If flags
has the SV_GMAGIC
bit set, does an mg_get()
first. Normally used via the SvIV(sv)
and SvIVx(sv)
macros.
IV sv_2iv_flags(SV * const sv, const I32 flags)
SvIV_set
Set the value of the IV pointer in sv to val. It is possible to perform the same function of this macro with an lvalue assignment to SvIVX
. With future Perls, however, it will be more efficient to use SvIV_set
instead of the lvalue assignment to SvIVX
.
void SvIV_set(SV* sv, IV val)
SvIVX
Returns the raw value in the SV's IV slot, without checks or conversions. Only use when you are sure SvIOK
is true. See also "SvIV"
.
IV SvIVX(SV* sv)
SvLEN
Returns the size of the string buffer in the SV, not including any part attributable to SvOOK
. See "SvCUR"
.
STRLEN SvLEN(SV* sv)
sv_len
Returns the length of the string in the SV. Handles magic and type coercion and sets the UTF8 flag appropriately. See also "SvCUR"
, which gives raw access to the xpv_cur
slot.
STRLEN sv_len(SV * const sv)
SvLEN_set
Set the size of the string buffer for the SV. See "SvLEN"
.
void SvLEN_set(SV* sv, STRLEN len)
sv_len_utf8
sv_len_utf8_nomg
These return the number of characters in the string in an SV, counting wide UTF-8 bytes as a single character. Both handle type coercion. They differ only in that sv_len_utf8
performs 'get' magic; sv_len_utf8_nomg
skips any magic.
STRLEN sv_len_utf8(SV * const sv)
SvLOCK
Arranges for a mutual exclusion lock to be obtained on sv
if a suitable module has been loaded.
void SvLOCK(SV* sv)
sv_magic
Adds magic to an SV. First upgrades sv
to type SVt_PVMG
if necessary, then adds a new magic item of type how
to the head of the magic list.
See "sv_magicext"
(which sv_magic
now calls) for a description of the handling of the name
and namlen
arguments.
You need to use sv_magicext
to add magic to SvREADONLY
SVs and also to add more than one instance of the same how
.
void sv_magic(SV * const sv, SV * const obj, const int how,
const char * const name, const I32 namlen)
sv_magicext
Adds magic to an SV, upgrading it if necessary. Applies the supplied vtable
and returns a pointer to the magic added.
Note that sv_magicext
will allow things that sv_magic
will not. In particular, you can add magic to SvREADONLY
SVs, and add more than one instance of the same how
.
If namlen
is greater than zero then a savepvn
copy of name
is stored, if namlen
is zero then name
is stored as-is and - as another special case - if (name && namlen == HEf_SVKEY)
then name
is assumed to contain an SV* and is stored as-is with its REFCNT
incremented.
(This is now used as a subroutine by sv_magic
.)
MAGIC * sv_magicext(SV * const sv, SV * const obj, const int how,
const MGVTBL * const vtbl,
const char * const name, const I32 namlen)
SvMAGIC_set
Set the value of the MAGIC pointer in sv
to val. See "SvIV_set"
.
void SvMAGIC_set(SV* sv, MAGIC* val)
sv_2mortal
Marks an existing SV as mortal. The SV will be destroyed "soon", either by an explicit call to FREETMPS
, or by an implicit call at places such as statement boundaries. SvTEMP()
is turned on which means that the SV's string buffer can be "stolen" if this SV is copied. See also "sv_newmortal"
and "sv_mortalcopy"
.
SV * sv_2mortal(SV * const sv)
sv_mortalcopy
Creates a new SV which is a copy of the original SV (using sv_setsv
). The new SV is marked as mortal. It will be destroyed "soon", either by an explicit call to FREETMPS
, or by an implicit call at places such as statement boundaries. See also "sv_newmortal"
and "sv_2mortal"
.
SV * sv_mortalcopy(SV * const oldsv)
sv_mortalcopy_flags
Like sv_mortalcopy
, but the extra flags
are passed to the sv_setsv_flags
.
SV * sv_mortalcopy_flags(SV * const oldsv, U32 flags)
sv_newmortal
Creates a new null SV which is mortal. The reference count of the SV is set to 1. It will be destroyed "soon", either by an explicit call to FREETMPS
, or by an implicit call at places such as statement boundaries. See also "sv_mortalcopy"
and "sv_2mortal"
.
SV * sv_newmortal()
SvNIOK
Returns a U32 value indicating whether the SV contains a number, integer or double.
U32 SvNIOK(SV* sv)
SvNIOK_off
Unsets the NV/IV status of an SV.
void SvNIOK_off(SV* sv)
SvNIOKp
Returns a U32 value indicating whether the SV contains a number, integer or double. Checks the private setting. Use SvNIOK
instead.
U32 SvNIOKp(SV* sv)
SvNOK
Returns a U32 value indicating whether the SV contains a double.
U32 SvNOK(SV* sv)
SvNOK_off
Unsets the NV status of an SV.
void SvNOK_off(SV* sv)
SvNOK_on
Tells an SV that it is a double.
void SvNOK_on(SV* sv)
SvNOK_only
Tells an SV that it is a double and disables all other OK bits.
void SvNOK_only(SV* sv)
SvNOKp
Returns a U32 value indicating whether the SV contains a double. Checks the private setting. Use SvNOK
instead.
U32 SvNOKp(SV* sv)
sv_nolocking
DEPRECATED!
It is planned to remove sv_nolocking
from a future release of Perl. Do not use it for new code; remove it from existing code.
Dummy routine which "locks" an SV when there is no locking module present. Exists to avoid test for a NULL
function pointer and because it could potentially warn under some level of strict-ness.
"Superseded" by sv_nosharing()
.
void sv_nolocking(SV *sv)
sv_nounlocking
DEPRECATED!
It is planned to remove sv_nounlocking
from a future release of Perl. Do not use it for new code; remove it from existing code.
Dummy routine which "unlocks" an SV when there is no locking module present. Exists to avoid test for a NULL
function pointer and because it could potentially warn under some level of strict-ness.
"Superseded" by sv_nosharing()
.
void sv_nounlocking(SV *sv)
sv_numeq
A convenient shortcut for calling sv_numeq_flags
with the SV_GMAGIC
flag. This function basically behaves like the Perl code $sv1 == $sv2
.
bool sv_numeq(SV *sv1, SV *sv2)
sv_numeq_flags
Returns a boolean indicating whether the numbers in the two SVs are identical. If the flags argument has the SV_GMAGIC
bit set, it handles get-magic too. Will coerce its args to numbers if necessary. Treats NULL
as undef.
If flags does not have the SV_SKIP_OVERLOAD
bit set, an attempt to use ==
overloading will be made. If such overloading does not exist or the flag is set, then regular numerical comparison will be used instead.
bool sv_numeq_flags(SV *sv1, SV *sv2, const U32 flags)
SvNV
SvNV_nomg
SvNVx
These each coerce the given SV to NV and return it. The returned value in many circumstances will get stored in sv
's NV slot, but not in all cases. (Use "sv_setnv"
to make sure it does).
As of 5.37.1, all are guaranteed to evaluate sv
only once.
SvNVx
is now identical to SvNV
, but prior to 5.37.1, it was the only form guaranteed to evaluate sv
only once.
SvNV_nomg
is the same as SvNV
, but does not perform 'get' magic.
NV SvNV(SV *sv)
sv_2nv_flags
Return the num value of an SV, doing any necessary string or integer conversion. If flags
has the SV_GMAGIC
bit set, does an mg_get()
first. Normally used via the SvNV(sv)
and SvNVx(sv)
macros.
NV sv_2nv_flags(SV * const sv, const I32 flags)
SvNV_set
Set the value of the NV pointer in sv
to val. See "SvIV_set"
.
void SvNV_set(SV* sv, NV val)
SvNVX
Returns the raw value in the SV's NV slot, without checks or conversions. Only use when you are sure SvNOK
is true. See also "SvNV"
.
NV SvNVX(SV* sv)
SvOK
Returns a U32 value indicating whether the value is defined. This is only meaningful for scalars.
U32 SvOK(SV* sv)
SvOOK
Returns a U32 indicating whether the pointer to the string buffer is offset. This hack is used internally to speed up removal of characters from the beginning of a "SvPV"
. When SvOOK
is true, then the start of the allocated string buffer is actually SvOOK_offset()
bytes before SvPVX
. This offset used to be stored in SvIVX
, but is now stored within the spare part of the buffer.
U32 SvOOK(SV* sv)
SvOOK_off
Remove any string offset.
void SvOOK_off(SV * sv)
SvOOK_offset
Reads into len
the offset from SvPVX
back to the true start of the allocated buffer, which will be non-zero if sv_chop
has been used to efficiently remove characters from start of the buffer. Implemented as a macro, which takes the address of len
, which must be of type STRLEN
. Evaluates sv
more than once. Sets len
to 0 if SvOOK(sv)
is false.
void SvOOK_offset(SV*sv, STRLEN len)
SvPOK
Returns a U32 value indicating whether the SV contains a character string.
U32 SvPOK(SV* sv)
SvPOK_off
Unsets the PV status of an SV.
void SvPOK_off(SV* sv)
SvPOK_on
Tells an SV that it is a string.
void SvPOK_on(SV* sv)
SvPOK_only
Tells an SV that it is a string and disables all other OK
bits. Will also turn off the UTF-8 status.
void SvPOK_only(SV* sv)
SvPOK_only_UTF8
Tells an SV that it is a string and disables all other OK
bits, and leaves the UTF-8 status as it was.
void SvPOK_only_UTF8(SV* sv)
SvPOKp
Returns a U32 value indicating whether the SV contains a character string. Checks the private setting. Use SvPOK
instead.
U32 SvPOKp(SV* sv)
sv_pos_b2u
Converts the value pointed to by offsetp
from a count of bytes from the start of the string, to a count of the equivalent number of UTF-8 chars. Handles magic and type coercion.
Use sv_pos_b2u_flags
in preference, which correctly handles strings longer than 2Gb.
void sv_pos_b2u(SV * const sv, I32 * const offsetp)
sv_pos_b2u_flags
Converts offset
from a count of bytes from the start of the string, to a count of the equivalent number of UTF-8 chars. Handles type coercion. flags
is passed to SvPV_flags
, and usually should be SV_GMAGIC|SV_CONST_RETURN
to handle magic.
STRLEN sv_pos_b2u_flags(SV * const sv, STRLEN const offset,
U32 flags)
sv_pos_u2b
Converts the value pointed to by offsetp
from a count of UTF-8 chars from the start of the string, to a count of the equivalent number of bytes; if lenp
is non-zero, it does the same to lenp
, but this time starting from the offset, rather than from the start of the string. Handles magic and type coercion.
Use sv_pos_u2b_flags
in preference, which correctly handles strings longer than 2Gb.
void sv_pos_u2b(SV * const sv, I32 * const offsetp,
I32 * const lenp)
sv_pos_u2b_flags
Converts the offset from a count of UTF-8 chars from the start of the string, to a count of the equivalent number of bytes; if lenp
is non-zero, it does the same to lenp
, but this time starting from offset
, rather than from the start of the string. Handles type coercion. flags
is passed to SvPV_flags
, and usually should be SV_GMAGIC|SV_CONST_RETURN
to handle magic.
STRLEN sv_pos_u2b_flags(SV * const sv, STRLEN uoffset,
STRLEN * const lenp, U32 flags)
SvPV
SvPV_const
SvPV_flags
SvPV_flags_const
SvPV_flags_mutable
SvPV_mutable
SvPV_nolen
SvPV_nolen_const
SvPV_nomg
SvPV_nomg_const
SvPV_nomg_const_nolen
SvPV_nomg_nolen
SvPVbyte
SvPVbyte_nolen
SvPVbyte_nomg
SvPVbyte_or_null
SvPVbyte_or_null_nomg
SvPVbytex
SvPVbytex_nolen
SvPVutf8
SvPVutf8_nolen
SvPVutf8_nomg
SvPVutf8_or_null
SvPVutf8_or_null_nomg
SvPVutf8x
SvPVx
SvPVx_const
SvPVx_nolen
SvPVx_nolen_const
These each return a pointer to the string in sv
, or a stringified form of sv
if it does not contain a string. The SV may cache the stringified version becoming SvPOK
.
This is a very basic and common operation, so there are lots of slightly different versions of it.
Note that there is no guarantee that the return value of SvPV(sv)
, for example, is equal to SvPVX(sv)
, or that SvPVX(sv)
contains valid data, or that successive calls to SvPV(sv)
(or another of these forms) will return the same pointer value each time. This is due to the way that things like overloading and Copy-On-Write are handled. In these cases, the return value may point to a temporary buffer or similar. If you absolutely need the SvPVX
field to be valid (for example, if you intend to write to it), then see "SvPV_force"
.
The differences between the forms are:
The forms with neither byte
nor utf8
in their names (e.g., SvPV
or SvPV_nolen
) can expose the SV's internal string buffer. If that buffer consists entirely of bytes 0-255 and includes any bytes above 127, then you MUST consult SvUTF8
to determine the actual code points the string is meant to contain. Generally speaking, it is probably safer to prefer SvPVbyte
, SvPVutf8
, and the like. See "How do I pass a Perl string to a C library?" in perlguts for more details.
The forms with flags
in their names allow you to use the flags
parameter to specify to process 'get' magic (by setting the SV_GMAGIC
flag) or to skip 'get' magic (by clearing it). The other forms process 'get' magic, except for the ones with nomg
in their names, which skip 'get' magic.
The forms that take a len
parameter will set that variable to the byte length of the resultant string (these are macros, so don't use &len
).
The forms with nolen
in their names indicate they don't have a len
parameter. They should be used only when it is known that the PV is a C string, terminated by a NUL byte, and without intermediate NUL characters; or when you don't care about its length.
The forms with const
in their names return const char *
so that the compiler will hopefully complain if you were to try to modify the contents of the string (unless you cast away const yourself).
The other forms return a mutable pointer so that the string is modifiable by the caller; this is emphasized for the ones with mutable
in their names.
As of 5.38, all forms are guaranteed to evaluate sv
exactly once. For earlier Perls, use a form whose name ends with x
for single evaluation.
SvPVutf8
is like SvPV
, but converts sv
to UTF-8 first if not already UTF-8. Similarly, the other forms with utf8
in their names correspond to their respective forms without.
SvPVutf8_or_null
and SvPVutf8_or_null_nomg
don't have corresponding non-utf8
forms. Instead they are like SvPVutf8_nomg
, but when sv
is undef, they return NULL
.
SvPVbyte
is like SvPV
, but converts sv
to byte representation first if currently encoded as UTF-8. If sv
cannot be downgraded from UTF-8, it croaks. Similarly, the other forms with byte
in their names correspond to their respective forms without.
SvPVbyte_or_null
doesn't have a corresponding non-byte
form. Instead it is like SvPVbyte
, but when sv
is undef, it returns NULL
.
char* SvPV (SV* sv, STRLEN len)
const char* SvPV_const (SV* sv, STRLEN len)
char* SvPV_flags (SV* sv, STRLEN len, U32 flags)
const char* SvPV_flags_const (SV* sv, STRLEN len, U32 flags)
char* SvPV_flags_mutable (SV* sv, STRLEN len, U32 flags)
char* SvPV_mutable (SV* sv, STRLEN len)
char* SvPV_nolen (SV* sv)
const char* SvPV_nolen_const (SV* sv)
char* SvPV_nomg (SV* sv, STRLEN len)
const char* SvPV_nomg_const (SV* sv, STRLEN len)
const char* SvPV_nomg_const_nolen(SV* sv)
char* SvPV_nomg_nolen (SV* sv)
char* SvPVbyte (SV* sv, STRLEN len)
char* SvPVbyte_nolen (SV* sv)
char* SvPVbyte_nomg (SV* sv, STRLEN len)
char* SvPVbyte_or_null (SV* sv, STRLEN len)
char* SvPVbyte_or_null_nomg(SV* sv, STRLEN len)
char* SvPVbytex (SV* sv, STRLEN len)
char* SvPVbytex_nolen (SV* sv)
char* SvPVutf8 (SV* sv, STRLEN len)
char* SvPVutf8_nolen (SV* sv)
char* SvPVutf8_nomg (SV* sv, STRLEN len)
char* SvPVutf8_or_null (SV* sv, STRLEN len)
char* SvPVutf8_or_null_nomg(SV* sv, STRLEN len)
char* SvPVutf8x (SV* sv, STRLEN len)
char* SvPVx (SV* sv, STRLEN len)
const char* SvPVx_const (SV* sv, STRLEN len)
char* SvPVx_nolen (SV* sv)
const char* SvPVx_nolen_const (SV* sv)
sv_2pv
sv_2pv_flags
These implement the various forms of the "SvPV
" in perlapi macros. The macros are the preferred interface.
These return a pointer to the string value of an SV (coercing it to a string if necessary), and set *lp
to its length in bytes.
The forms differ in that plain sv_2pvbyte
always processes 'get' magic; and sv_2pvbyte_flags
processes 'get' magic if and only if flags
contains SV_GMAGIC
.
char * sv_2pv (SV *sv, STRLEN *lp)
char * sv_2pv_flags(SV * const sv, STRLEN * const lp,
const U32 flags)
sv_2pvbyte
sv_2pvbyte_flags
These implement the various forms of the "SvPVbyte
" in perlapi macros. The macros are the preferred interface.
These return a pointer to the byte-encoded representation of the SV, and set *lp
to its length. If the SV is marked as being encoded as UTF-8, it will be downgraded, if possible, to a byte string. If the SV cannot be downgraded, they croak.
The forms differ in that plain sv_2pvbyte
always processes 'get' magic; and sv_2pvbyte_flags
processes 'get' magic if and only if flags
contains SV_GMAGIC
.
char * sv_2pvbyte (SV *sv, STRLEN * const lp)
char * sv_2pvbyte_flags(SV *sv, STRLEN * const lp,
const U32 flags)
SvPVCLEAR
Ensures that sv is a SVt_PV and that its SvCUR is 0, and that it is properly null terminated. Equivalent to sv_setpvs(""), but more efficient.
char * SvPVCLEAR(SV* sv)
SvPVCLEAR_FRESH
Like SvPVCLEAR, but optimized for newly-minted SVt_PV/PVIV/PVNV/PVMG that already have a PV buffer allocated, but no SvTHINKFIRST.
char * SvPVCLEAR_FRESH(SV* sv)
SvPV_force
SvPV_force_flags
SvPV_force_flags_mutable
SvPV_force_flags_nolen
SvPV_force_mutable
SvPV_force_nolen
SvPV_force_nomg
SvPV_force_nomg_nolen
SvPVbyte_force
SvPVbytex_force
SvPVutf8_force
SvPVutf8x_force
SvPVx_force
These are like "SvPV"
, returning the string in the SV, but will force the SV into containing a string ("SvPOK"
), and only a string ("SvPOK_only"
), by hook or by crook. You need to use one of these force
routines if you are going to update the "SvPVX"
directly.
Note that coercing an arbitrary scalar into a plain PV will potentially strip useful data from it. For example if the SV was SvROK
, then the referent will have its reference count decremented, and the SV itself may be converted to an SvPOK
scalar with a string buffer containing a value such as "ARRAY(0x1234)"
.
The differences between the forms are:
The forms with flags
in their names allow you to use the flags
parameter to specify to perform 'get' magic (by setting the SV_GMAGIC
flag) or to skip 'get' magic (by clearing it). The other forms do perform 'get' magic, except for the ones with nomg
in their names, which skip 'get' magic.
The forms that take a len
parameter will set that variable to the byte length of the resultant string (these are macros, so don't use &len
).
The forms with nolen
in their names indicate they don't have a len
parameter. They should be used only when it is known that the PV is a C string, terminated by a NUL byte, and without intermediate NUL characters; or when you don't care about its length.
The forms with mutable
in their names are effectively the same as those without, but the name emphasizes that the string is modifiable by the caller, which it is in all the forms.
SvPVutf8_force
is like SvPV_force
, but converts sv
to UTF-8 first if not already UTF-8.
SvPVutf8x_force
is like SvPVutf8_force
, but guarantees to evaluate sv
only once; use the more efficient SvPVutf8_force
otherwise.
SvPVbyte_force
is like SvPV_force
, but converts sv
to byte representation first if currently encoded as UTF-8. If the SV cannot be downgraded from UTF-8, this croaks.
SvPVbytex_force
is like SvPVbyte_force
, but guarantees to evaluate sv
only once; use the more efficient SvPVbyte_force
otherwise.
char* SvPV_force (SV* sv, STRLEN len)
char* SvPV_force_flags (SV * sv, STRLEN len, U32 flags)
char* SvPV_force_flags_mutable(SV * sv, STRLEN len, U32 flags)
char* SvPV_force_flags_nolen (SV * sv, U32 flags)
char* SvPV_force_mutable (SV * sv, STRLEN len)
char* SvPV_force_nolen (SV* sv)
char* SvPV_force_nomg (SV* sv, STRLEN len)
char* SvPV_force_nomg_nolen (SV * sv)
char* SvPVbyte_force (SV * sv, STRLEN len)
char* SvPVbytex_force (SV * sv, STRLEN len)
char* SvPVutf8_force (SV * sv, STRLEN len)
char* SvPVutf8x_force (SV * sv, STRLEN len)
char* SvPVx_force (SV* sv, STRLEN len)
SvPV_free
Frees the PV buffer in sv
, leaving things in a precarious state, so should only be used as part of a larger operation
void SvPV_free(SV * sv)
sv_pvn_force_flags
Get a sensible string out of the SV somehow. If flags
has the SV_GMAGIC
bit set, will "mg_get"
on sv
if appropriate, else not. sv_pvn_force
and sv_pvn_force_nomg
are implemented in terms of this function. You normally want to use the various wrapper macros instead: see "SvPV_force"
and "SvPV_force_nomg"
.
char * sv_pvn_force_flags(SV * const sv, STRLEN * const lp,
const U32 flags)
SvPV_renew
Low level micro optimization of "SvGROW"
. It is generally better to use SvGROW
instead. This is because SvPV_renew
ignores potential issues that SvGROW
handles. sv
needs to have a real PV
that is unencumbered by things like COW. Using SV_CHECK_THINKFIRST
or SV_CHECK_THINKFIRST_COW_DROP
before calling this should clean it up, but why not just use SvGROW
if you're not sure about the provenance?
void SvPV_renew(SV* sv, STRLEN len)
SvPV_set
This is probably not what you want to use, you probably wanted "sv_usepvn_flags" or "sv_setpvn" or "sv_setpvs".
Set the value of the PV pointer in sv
to the Perl allocated NUL
-terminated string val
. See also "SvIV_set"
.
Remember to free the previous PV buffer. There are many things to check. Beware that the existing pointer may be involved in copy-on-write or other mischief, so do SvOOK_off(sv)
and use sv_force_normal
or SvPV_force
(or check the SvIsCOW
flag) first to make sure this modification is safe. Then finally, if it is not a COW, call "SvPV_free"
to free the previous PV buffer.
void SvPV_set(SV* sv, char* val)
SvPV_shrink_to_cur
Trim any trailing unused memory in the PV of sv
, which needs to have a real PV
that is unencumbered by things like COW. Think first before using this functionality. Is the space saving really worth giving up COW? Will the needed size of sv
stay the same?
If the answers are both yes, then use "SV_CHECK_THINKFIRST
" or "SV_CHECK_THINKFIRST_COW_DROP
" before calling this.
void SvPV_shrink_to_cur(SV* sv)
sv_2pvutf8
sv_2pvutf8_flags
These implement the various forms of the "SvPVutf8
" in perlapi macros. The macros are the preferred interface.
These return a pointer to the UTF-8-encoded representation of the SV, and set *lp
to its length in bytes. They may cause the SV to be upgraded to UTF-8 as a side-effect.
The forms differ in that plain sv_2pvutf8
always processes 'get' magic; and sv_2pvutf8_flags
processes 'get' magic if and only if flags
contains SV_GMAGIC
.
char * sv_2pvutf8 (SV *sv, STRLEN * const lp)
char * sv_2pvutf8_flags(SV *sv, STRLEN * const lp,
const U32 flags)
SvPVX
SvPVX_const
SvPVX_mutable
SvPVXx
These return a pointer to the physical string in the SV. The SV must contain a string. Prior to 5.9.3 it is not safe to execute these unless the SV's type >= SVt_PV
.
These are also used to store the name of an autoloaded subroutine in an XS AUTOLOAD routine. See "Autoloading with XSUBs" in perlguts.
SvPVXx
is identical to SvPVX
.
SvPVX_mutable
is merely a synonym for SvPVX
, but its name emphasizes that the string is modifiable by the caller.
SvPVX_const
differs in that the return value has been cast so that the compiler will complain if you were to try to modify the contents of the string, (unless you cast away const yourself).
char* SvPVX (SV* sv)
const char* SvPVX_const (SV* sv)
char* SvPVX_mutable(SV* sv)
char* SvPVXx (SV* sv)
SvPVXtrue
Returns a boolean as to whether or not sv
contains a PV that is considered TRUE. FALSE is returned if sv
doesn't contain a PV, or if the PV it does contain is zero length, or consists of just the single character '0'. Every other PV value is considered TRUE.
As of Perl v5.37.1, sv
is evaluated exactly once; in earlier releases, it could be evaluated more than once.
bool SvPVXtrue(SV *sv)
SvREADONLY
Returns true if the argument is readonly, otherwise returns false. Exposed to perl code via Internals::SvREADONLY().
U32 SvREADONLY(SV* sv)
SvREADONLY_off
Mark an object as not-readonly. Exactly what this mean depends on the object type. Exposed to perl code via Internals::SvREADONLY().
U32 SvREADONLY_off(SV* sv)
SvREADONLY_on
Mark an object as readonly. Exactly what this means depends on the object type. Exposed to perl code via Internals::SvREADONLY().
U32 SvREADONLY_on(SV* sv)
sv_ref
Returns a SV describing what the SV passed in is a reference to.
dst can be a SV to be set to the description or NULL, in which case a mortal SV is returned.
If ob is true and the SV is blessed, the description is the class name, otherwise it is the type of the SV, "SCALAR", "ARRAY" etc.
SV * sv_ref(SV *dst, const SV * const sv, const int ob)
SvREFCNT
Returns the value of the object's reference count. Exposed to perl code via Internals::SvREFCNT().
U32 SvREFCNT(SV* sv)
SvREFCNT_dec
SvREFCNT_dec_set_NULL
SvREFCNT_dec_ret_NULL
SvREFCNT_dec_NN
These decrement the reference count of the given SV.
SvREFCNT_dec_NN
may only be used when sv
is known to not be NULL
.
The function SvREFCNT_dec_ret_NULL()
is identical to the SvREFCNT_dec()
except it returns a NULL SV *
. It is used by SvREFCNT_dec_set_NULL()
which is a macro which will, when passed a non-NULL argument, decrement the reference count of its argument and then set it to NULL. You can replace code of the following form:
if (sv) {
SvREFCNT_dec_NN(sv);
sv = NULL;
}
with
SvREFCNT_dec_set_NULL(sv);
void SvREFCNT_dec (SV *sv)
void SvREFCNT_dec_set_NULL(SV *sv)
SV * SvREFCNT_dec_ret_NULL(SV *sv)
void SvREFCNT_dec_NN (SV *sv)
SvREFCNT_inc
SvREFCNT_inc_NN
SvREFCNT_inc_simple
SvREFCNT_inc_simple_NN
SvREFCNT_inc_simple_void
SvREFCNT_inc_simple_void_NN
SvREFCNT_inc_void
SvREFCNT_inc_void_NN
These all increment the reference count of the given SV. The ones without void
in their names return the SV.
SvREFCNT_inc
is the base operation; the rest are optimizations if various input constraints are known to be true; hence, all can be replaced with SvREFCNT_inc
.
SvREFCNT_inc_NN
can only be used if you know sv
is not NULL
. Since we don't have to check the NULLness, it's faster and smaller.
SvREFCNT_inc_void
can only be used if you don't need the return value. The macro doesn't need to return a meaningful value.
SvREFCNT_inc_void_NN
can only be used if you both don't need the return value, and you know that sv
is not NULL
. The macro doesn't need to return a meaningful value, or check for NULLness, so it's smaller and faster.
SvREFCNT_inc_simple
can only be used with expressions without side effects. Since we don't have to store a temporary value, it's faster.
SvREFCNT_inc_simple_NN
can only be used with expressions without side effects and you know sv
is not NULL
. Since we don't have to store a temporary value, nor check for NULLness, it's faster and smaller.
SvREFCNT_inc_simple_void
can only be used with expressions without side effects and you don't need the return value.
SvREFCNT_inc_simple_void_NN
can only be used with expressions without side effects, you don't need the return value, and you know sv
is not NULL
.
SV * SvREFCNT_inc (SV *sv)
SV * SvREFCNT_inc_NN (SV *sv)
SV* SvREFCNT_inc_simple (SV* sv)
SV* SvREFCNT_inc_simple_NN (SV* sv)
void SvREFCNT_inc_simple_void (SV* sv)
void SvREFCNT_inc_simple_void_NN(SV* sv)
void SvREFCNT_inc_void (SV *sv)
void SvREFCNT_inc_void_NN (SV* sv)
sv_reftype
Returns a string describing what the SV is a reference to.
If ob is true and the SV is blessed, the string is the class name, otherwise it is the type of the SV, "SCALAR", "ARRAY" etc.
const char * sv_reftype(const SV * const sv, const int ob)
sv_replace
Make the first argument a copy of the second, then delete the original. The target SV physically takes over ownership of the body of the source SV and inherits its flags; however, the target keeps any magic it owns, and any magic in the source is discarded. Note that this is a rather specialist SV copying operation; most of the time you'll want to use sv_setsv
or one of its many macro front-ends.
void sv_replace(SV * const sv, SV * const nsv)
sv_report_used
Dump the contents of all SVs not yet freed (debugging aid).
void sv_report_used()
sv_reset
Underlying implementation for the reset
Perl function. Note that the perl-level function is vaguely deprecated.
void sv_reset(const char *s, HV * const stash)
SvROK
Tests if the SV is an RV.
U32 SvROK(SV* sv)
SvROK_off
Unsets the RV status of an SV.
void SvROK_off(SV* sv)
SvROK_on
Tells an SV that it is an RV.
void SvROK_on(SV* sv)
SvRV
Dereferences an RV to return the SV.
SV* SvRV(SV* sv)
SvRV_set
Set the value of the RV pointer in sv
to val. See "SvIV_set"
.
void SvRV_set(SV* sv, SV* val)
sv_rvunweaken
Unweaken a reference: Clear the SvWEAKREF
flag on this RV; remove the backreference to this RV from the array of backreferences associated with the target SV, increment the refcount of the target. Silently ignores undef
and warns on non-weak references.
SV * sv_rvunweaken(SV * const sv)
sv_rvweaken
Weaken a reference: set the SvWEAKREF
flag on this RV; give the referred-to SV PERL_MAGIC_backref
magic if it hasn't already; and push a back-reference to this RV onto the array of backreferences associated with that magic. If the RV is magical, set magic will be called after the RV is cleared. Silently ignores undef
and warns on already-weak references.
SV * sv_rvweaken(SV * const sv)
sv_setbool
sv_setbool_mg
These set an SV to a true or false boolean value, upgrading first if necessary.
They differ only in that sv_setbool_mg
handles 'set' magic; sv_setbool
does not.
void sv_setbool(SV *sv, bool b)
sv_set_bool
Equivalent to sv_setsv(sv, bool_val ? &Pl_sv_yes : &PL_sv_no)
, but may be made more efficient in the future. Doesn't handle set magic.
The perl equivalent is $sv = !!$expr;
.
Introduced in perl 5.35.11.
void sv_set_bool(SV *sv, const bool bool_val)
sv_set_false
Equivalent to sv_setsv(sv, &PL_sv_no)
, but may be made more efficient in the future. Doesn't handle set magic.
The perl equivalent is $sv = !1;
.
Introduced in perl 5.35.11.
void sv_set_false(SV *sv)
sv_setiv
sv_setiv_mg
These copy an integer into the given SV, upgrading first if necessary.
They differ only in that sv_setiv_mg
handles 'set' magic; sv_setiv
does not.
void sv_setiv (SV * const sv, const IV num)
void sv_setiv_mg(SV * const sv, const IV i)
SvSETMAGIC
Invokes "mg_set"
on an SV if it has 'set' magic. This is necessary after modifying a scalar, in case it is a magical variable like $|
or a tied variable (it calls STORE
). This macro evaluates its argument more than once.
void SvSETMAGIC(SV* sv)
SvSetMagicSV
SvSetMagicSV_nosteal
SvSetSV
SvSetSV_nosteal
if dsv
is the same as ssv
, these do nothing. Otherwise they all call some form of "sv_setsv"
. They may evaluate their arguments more than once.
The only differences are:
SvSetMagicSV
and SvSetMagicSV_nosteal
perform any required 'set' magic afterwards on the destination SV; SvSetSV
and SvSetSV_nosteal
do not.
SvSetSV_nosteal
SvSetMagicSV_nosteal
call a non-destructive version of sv_setsv
.
void SvSetMagicSV(SV* dsv, SV* ssv)
sv_setnv
sv_setnv_mg
These copy a double into the given SV, upgrading first if necessary.
They differ only in that sv_setnv_mg
handles 'set' magic; sv_setnv
does not.
void sv_setnv(SV * const sv, const NV num)
sv_setpv
sv_setpv_mg
sv_setpvn
sv_setpvn_fresh
sv_setpvn_mg
sv_setpvs
sv_setpvs_mg
These copy a string into the SV sv
, making sure it is "SvPOK_only"
.
In the pvs
forms, the string must be a C literal string, enclosed in double quotes.
In the pvn
forms, the first byte of the string is pointed to by ptr
, and len
indicates the number of bytes to be copied, potentially including embedded NUL
characters.
In the plain pv
forms, ptr
points to a NUL-terminated C string. That is, it points to the first byte of the string, and the copy proceeds up through the first encountered NUL
byte.
In the forms that take a ptr
argument, if it is NULL, the SV will become undefined.
The UTF-8 flag is not changed by these functions.
A terminating NUL byte is guaranteed in the result.
The _mg
forms handle 'set' magic; the other forms skip all magic.
sv_setpvn_fresh
is a cut-down alternative to sv_setpvn
, intended ONLY to be used with a fresh sv that has been upgraded to a SVt_PV, SVt_PVIV, SVt_PVNV, or SVt_PVMG.
void sv_setpv (SV * const sv, const char * const ptr)
void sv_setpv_mg (SV * const sv, const char * const ptr)
void sv_setpvn (SV * const sv, const char * const ptr,
const STRLEN len)
void sv_setpvn_fresh(SV * const sv, const char * const ptr,
const STRLEN len)
void sv_setpvn_mg (SV * const sv, const char * const ptr,
const STRLEN len)
void sv_setpvs (SV* sv, "literal string")
void sv_setpvs_mg (SV* sv, "literal string")
sv_setpv_bufsize
Sets the SV to be a string of cur
bytes length, with at least len
bytes available. Ensures that there is a null byte at SvEND
.
Returns a char * pointer to the SvPV buffer.
The caller must set the first cur
bytes of sv
before the first use of its contents. This means that if cur
is zero, the SV is immediately fully formed and ready to use, just like any other SV containing an empty string.
char * sv_setpv_bufsize(SV * const sv, const STRLEN cur,
const STRLEN len)
sv_setpvf
sv_setpvf_mg
sv_setpvf_mg_nocontext
sv_setpvf_nocontext
These work like "sv_catpvf"
but copy the text into the SV instead of appending it.
The differences between these are:
sv_setpvf_mg
and sv_setpvf_mg_nocontext
perform 'set' magic; sv_setpvf
and sv_setpvf_nocontext
skip all magic.
sv_setpvf_nocontext
and sv_setpvf_mg_nocontext
do not take a thread context (aTHX
) parameter, so are used in situations where the caller doesn't already have the thread context.
The UTF-8 flag is not changed by these functions.
NOTE: sv_setpvf
must be explicitly called as Perl_sv_setpvf
with an aTHX_
parameter.
NOTE: sv_setpvf_mg
must be explicitly called as Perl_sv_setpvf_mg
with an aTHX_
parameter.
void Perl_sv_setpvf (pTHX_ SV * const sv,
const char * const pat, ...)
void Perl_sv_setpvf_mg (pTHX_ SV * const sv,
const char * const pat, ...)
void sv_setpvf_mg_nocontext(SV * const sv,
const char * const pat, ...)
void sv_setpvf_nocontext (SV * const sv,
const char * const pat, ...)
sv_setref_iv
Copies an integer into a new SV, optionally blessing the SV. The rv
argument will be upgraded to an RV. That RV will be modified to point to the new SV. The classname
argument indicates the package for the blessing. Set classname
to NULL
to avoid the blessing. The new SV will have a reference count of 1, and the RV will be returned.
SV * sv_setref_iv(SV * const rv, const char * const classname,
const IV iv)
sv_setref_nv
Copies a double into a new SV, optionally blessing the SV. The rv
argument will be upgraded to an RV. That RV will be modified to point to the new SV. The classname
argument indicates the package for the blessing. Set classname
to NULL
to avoid the blessing. The new SV will have a reference count of 1, and the RV will be returned.
SV * sv_setref_nv(SV * const rv, const char * const classname,
const NV nv)
sv_setref_pv
Copies a pointer into a new SV, optionally blessing the SV. The rv
argument will be upgraded to an RV. That RV will be modified to point to the new SV. If the pv
argument is NULL
, then PL_sv_undef
will be placed into the SV. The classname
argument indicates the package for the blessing. Set classname
to NULL
to avoid the blessing. The new SV will have a reference count of 1, and the RV will be returned.
Do not use with other Perl types such as HV, AV, SV, CV, because those objects will become corrupted by the pointer copy process.
Note that sv_setref_pvn
copies the string while this copies the pointer.
SV * sv_setref_pv(SV * const rv, const char * const classname,
void * const pv)
sv_setref_pvn
Copies a string into a new SV, optionally blessing the SV. The length of the string must be specified with n
. The rv
argument will be upgraded to an RV. That RV will be modified to point to the new SV. The classname
argument indicates the package for the blessing. Set classname
to NULL
to avoid the blessing. The new SV will have a reference count of 1, and the RV will be returned.
Note that sv_setref_pv
copies the pointer while this copies the string.
SV * sv_setref_pvn(SV * const rv, const char * const classname,
const char * const pv, const STRLEN n)
sv_setref_pvs
Like sv_setref_pvn
, but takes a literal string instead of a string/length pair.
SV * sv_setref_pvs(SV *const rv, const char *const classname,
"literal string")
sv_setref_uv
Copies an unsigned integer into a new SV, optionally blessing the SV. The rv
argument will be upgraded to an RV. That RV will be modified to point to the new SV. The classname
argument indicates the package for the blessing. Set classname
to NULL
to avoid the blessing. The new SV will have a reference count of 1, and the RV will be returned.
SV * sv_setref_uv(SV * const rv, const char * const classname,
const UV uv)
sv_setrv_inc
sv_setrv_inc_mg
As sv_setrv_noinc
but increments the reference count of ref.
sv_setrv_inc_mg
will invoke 'set' magic on the SV; sv_setrv_inc
will not.
void sv_setrv_inc(SV * const sv, SV * const ref)
sv_setrv_noinc
sv_setrv_noinc_mg
Copies an SV pointer into the given SV as an SV reference, upgrading it if necessary. After this, SvRV(sv)
is equal to ref. This does not adjust the reference count of ref. The reference ref must not be NULL.
sv_setrv_noinc_mg
will invoke 'set' magic on the SV; sv_setrv_noinc
will not.
void sv_setrv_noinc(SV * const sv, SV * const ref)
sv_setsv
sv_setsv_flags
sv_setsv_mg
sv_setsv_nomg
These copy the contents of the source SV ssv
into the destination SV dsv
. ssv
may be destroyed if it is mortal, so don't use these functions if the source SV needs to be reused. Loosely speaking, they perform a copy-by-value, obliterating any previous content of the destination.
They differ only in that:
sv_setsv
calls 'get' magic on ssv
, but skips 'set' magic on dsv
.
sv_setsv_mg
calls both 'get' magic on ssv
and 'set' magic on dsv
.
sv_setsv_nomg
skips all magic.
sv_setsv_flags
has a flags
parameter which you can use to specify any combination of magic handling, and also you can specify SV_NOSTEAL
so that the buffers of temps will not be stolen.
You probably want to instead use one of the assortment of wrappers, such as "SvSetSV"
, "SvSetSV_nosteal"
, "SvSetMagicSV"
and "SvSetMagicSV_nosteal"
.
sv_setsv_flags
is the primary function for copying scalars, and most other copy-ish functions and macros use it underneath.
void sv_setsv (SV *dsv, SV *ssv)
void sv_setsv_flags(SV *dsv, SV *ssv, const I32 flags)
void sv_setsv_mg (SV * const dsv, SV * const ssv)
void sv_setsv_nomg (SV *dsv, SV *ssv)
sv_set_true
Equivalent to sv_setsv(sv, &PL_sv_yes)
, but may be made more efficient in the future. Doesn't handle set magic.
The perl equivalent is $sv = !0;
.
Introduced in perl 5.35.11.
void sv_set_true(SV *sv)
sv_set_undef
Equivalent to sv_setsv(sv, &PL_sv_undef)
, but more efficient. Doesn't handle set magic.
The perl equivalent is $sv = undef;
. Note that it doesn't free any string buffer, unlike undef $sv
.
Introduced in perl 5.25.12.
void sv_set_undef(SV *sv)
sv_setuv
sv_setuv_mg
These copy an unsigned integer into the given SV, upgrading first if necessary.
They differ only in that sv_setuv_mg
handles 'set' magic; sv_setuv
does not.
void sv_setuv (SV * const sv, const UV num)
void sv_setuv_mg(SV * const sv, const UV u)
SvSHARE
Arranges for sv
to be shared between threads if a suitable module has been loaded.
void SvSHARE(SV* sv)
SvSHARED_HASH
Returns the hash for sv
created by "newSVpvn_share"
.
struct hek* SvSHARED_HASH(SV * sv)
SvSTASH
Returns the stash of the SV.
HV* SvSTASH(SV* sv)
SvSTASH_set
Set the value of the STASH pointer in sv
to val. See "SvIV_set"
.
void SvSTASH_set(SV* sv, HV* val)
sv_streq
A convenient shortcut for calling sv_streq_flags
with the SV_GMAGIC
flag. This function basically behaves like the Perl code $sv1 eq $sv2
.
bool sv_streq(SV *sv1, SV *sv2)
sv_streq_flags
Returns a boolean indicating whether the strings in the two SVs are identical. If the flags argument has the SV_GMAGIC
bit set, it handles get-magic too. Will coerce its args to strings if necessary. Treats NULL
as undef. Correctly handles the UTF8 flag.
If flags does not have the SV_SKIP_OVERLOAD
bit set, an attempt to use eq
overloading will be made. If such overloading does not exist or the flag is set, then regular string comparison will be used instead.
bool sv_streq_flags(SV *sv1, SV *sv2, const U32 flags)
SvTRUE
SvTRUE_NN
SvTRUE_nomg
SvTRUE_nomg_NN
SvTRUEx
These return a boolean indicating whether Perl would evaluate the SV as true or false. See "SvOK"
for a defined/undefined test.
As of Perl 5.32, all are guaranteed to evaluate sv
only once. Prior to that release, only SvTRUEx
guaranteed single evaluation; now SvTRUEx
is identical to SvTRUE
.
SvTRUE_nomg
and TRUE_nomg_NN
do not perform 'get' magic; the others do unless the scalar is already SvPOK
, SvIOK
, or SvNOK
(the public, not the private flags).
SvTRUE_NN
is like "SvTRUE"
, but sv
is assumed to be non-null (NN). If there is a possibility that it is NULL, use plain SvTRUE
.
SvTRUE_nomg_NN
is like "SvTRUE_nomg"
, but sv
is assumed to be non-null (NN). If there is a possibility that it is NULL, use plain SvTRUE_nomg
.
bool SvTRUE(SV *sv)
SvUNLOCK
Releases a mutual exclusion lock on sv
if a suitable module has been loaded.
void SvUNLOCK(SV* sv)
sv_unmagic
Removes all magic of type type
from an SV.
int sv_unmagic(SV * const sv, const int type)
sv_unmagicext
Removes all magic of type type
with the specified vtbl
from an SV.
int sv_unmagicext(SV * const sv, const int type,
const MGVTBL *vtbl)
sv_unref
Unsets the RV status of the SV, and decrements the reference count of whatever was being referenced by the RV. This can almost be thought of as a reversal of newSVrv
. This is sv_unref_flags
with the flag
being zero. See "SvROK_off"
.
void sv_unref(SV *sv)
sv_unref_flags
Unsets the RV status of the SV, and decrements the reference count of whatever was being referenced by the RV. This can almost be thought of as a reversal of newSVrv
. The cflags
argument can contain SV_IMMEDIATE_UNREF
to force the reference count to be decremented (otherwise the decrementing is conditional on the reference count being different from one or the reference being a readonly SV). See "SvROK_off"
.
void sv_unref_flags(SV * const ref, const U32 flags)
SvUOK
Returns a boolean indicating whether the SV contains an integer that must be interpreted as unsigned. A non-negative integer whose value is within the range of both an IV and a UV may be flagged as either SvUOK
or SvIOK
.
bool SvUOK(SV* sv)
SvUPGRADE
Used to upgrade an SV to a more complex form. Uses sv_upgrade
to perform the upgrade if necessary. See "svtype"
.
void SvUPGRADE(SV* sv, svtype type)
sv_upgrade
Upgrade an SV to a more complex form. Generally adds a new body type to the SV, then copies across as much information as possible from the old body. It croaks if the SV is already in a more complex form than requested. You generally want to use the SvUPGRADE
macro wrapper, which checks the type before calling sv_upgrade
, and hence does not croak. See also "svtype"
.
void sv_upgrade(SV * const sv, svtype new_type)
sv_usepvn
sv_usepvn_flags
sv_usepvn_mg
These tell an SV to use ptr
for its string value. Normally SVs have their string stored inside the SV, but these tell the SV to use an external string instead.
ptr
should point to memory that was allocated by "Newx
". It must be the start of a Newx
-ed block of memory, and not a pointer to the middle of it (beware of OOK
and copy-on-write), and not be from a non-Newx
memory allocator like malloc
. The string length, len
, must be supplied. By default this function will "Renew
" (i.e. realloc, move) the memory pointed to by ptr
, so that the pointer should not be freed or used by the programmer after giving it to sv_usepvn
, and neither should any pointers from "behind" that pointer (e.g., ptr
+ 1) be used.
In the sv_usepvn_flags
form, if flags & SV_SMAGIC
is true, SvSETMAGIC
is called before returning. And if flags & SV_HAS_TRAILING_NUL
is true, then ptr[len]
must be NUL
, and the realloc will be skipped (i.e., the buffer is actually at least 1 byte longer than len
, and already meets the requirements for storing in SvPVX
).
sv_usepvn
is merely sv_usepvn_flags
with flags
set to 0, so 'set' magic is skipped.
sv_usepvn_mg
is merely sv_usepvn_flags
with flags
set to SV_SMAGIC
, so 'set' magic is performed.
void sv_usepvn (SV *sv, char *ptr, STRLEN len)
void sv_usepvn_flags(SV * const sv, char *ptr, const STRLEN len,
const U32 flags)
void sv_usepvn_mg (SV *sv, char *ptr, STRLEN len)
sv_utf8_decode
If the PV of the SV is an octet sequence in Perl's extended UTF-8 and contains a multiple-byte character, the SvUTF8
flag is turned on so that it looks like a character. If the PV contains only single-byte characters, the SvUTF8
flag stays off. Scans PV for validity and returns FALSE if the PV is invalid UTF-8.
bool sv_utf8_decode(SV * const sv)
sv_utf8_downgrade
sv_utf8_downgrade_flags
sv_utf8_downgrade_nomg
These attempt to convert the PV of an SV from characters to bytes. If the PV contains a character that cannot fit in a byte, this conversion will fail; in this case, FALSE
is returned if fail_ok
is true; otherwise they croak.
They are not a general purpose Unicode to byte encoding interface: use the Encode
extension for that.
They differ only in that:
sv_utf8_downgrade
processes 'get' magic on sv
.
sv_utf8_downgrade_nomg
does not.
sv_utf8_downgrade_flags
has an additional flags
parameter in which you can specify SV_GMAGIC
to process 'get' magic, or leave it cleared to not process 'get' magic.
bool sv_utf8_downgrade (SV * const sv, const bool fail_ok)
bool sv_utf8_downgrade_flags(SV * const sv, const bool fail_ok,
const U32 flags)
bool sv_utf8_downgrade_nomg (SV * const sv, const bool fail_ok)
sv_utf8_encode
Converts the PV of an SV to UTF-8, but then turns the SvUTF8
flag off so that it looks like octets again.
void sv_utf8_encode(SV * const sv)
SvUTF8_off
Unsets the UTF-8 status of an SV (the data is not changed, just the flag). Do not use frivolously.
void SvUTF8_off(SV *sv)
SvUTF8_on
Turn on the UTF-8 status of an SV (the data is not changed, just the flag). Do not use frivolously.
void SvUTF8_on(SV *sv)
sv_utf8_upgrade
sv_utf8_upgrade_flags
sv_utf8_upgrade_flags_grow
sv_utf8_upgrade_nomg
These convert the PV of an SV to its UTF-8-encoded form. The SV is forced to string form if it is not already. They always set the SvUTF8
flag to avoid future validity checks even if the whole string is the same in UTF-8 as not. They return the number of bytes in the converted string
The forms differ in just two ways. The main difference is whether or not they perform 'get magic' on sv
. sv_utf8_upgrade_nomg
skips 'get magic'; sv_utf8_upgrade
performs it; and sv_utf8_upgrade_flags
and sv_utf8_upgrade_flags_grow
either perform it (if the SV_GMAGIC
bit is set in flags
) or don't (if that bit is cleared).
The other difference is that sv_utf8_upgrade_flags_grow
has an additional parameter, extra
, which allows the caller to specify an amount of space to be reserved as spare beyond what is needed for the actual conversion. This is used when the caller knows it will soon be needing yet more space, and it is more efficient to request space from the system in a single call. This form is otherwise identical to sv_utf8_upgrade_flags
.
These are not a general purpose byte encoding to Unicode interface: use the Encode extension for that.
The SV_FORCE_UTF8_UPGRADE
flag is now ignored.
STRLEN sv_utf8_upgrade (SV *sv)
STRLEN sv_utf8_upgrade_flags (SV * const sv, const I32 flags)
STRLEN sv_utf8_upgrade_flags_grow(SV * const sv, const I32 flags,
STRLEN extra)
STRLEN sv_utf8_upgrade_nomg (SV *sv)
SvUTF8
Returns a U32 value indicating the UTF-8 status of an SV. If things are set-up properly, this indicates whether or not the SV contains UTF-8 encoded data. You should use this after a call to "SvPV"
or one of its variants, in case any call to string overloading updates the internal flag.
If you want to take into account the bytes pragma, use "DO_UTF8"
instead.
U32 SvUTF8(SV* sv)
SvUV
SvUV_nomg
SvUVx
These each coerce the given SV to UV and return it. The returned value in many circumstances will get stored in sv
's UV slot, but not in all cases. (Use "sv_setuv"
to make sure it does).
As of 5.37.1, all are guaranteed to evaluate sv
only once.
SvUVx
is now identical to SvUV
, but prior to 5.37.1, it was the only form guaranteed to evaluate sv
only once.
UV SvUV(SV *sv)
sv_2uv_flags
Return the unsigned integer value of an SV, doing any necessary string conversion. If flags
has the SV_GMAGIC
bit set, does an mg_get()
first. Normally used via the SvUV(sv)
and SvUVx(sv)
macros.
UV sv_2uv_flags(SV * const sv, const I32 flags)
SvUV_set
Set the value of the UV pointer in sv
to val. See "SvIV_set"
.
void SvUV_set(SV* sv, UV val)
SvUVX
Returns the raw value in the SV's UV slot, without checks or conversions. Only use when you are sure SvIOK
is true. See also "SvUV"
.
UV SvUVX(SV* sv)
SvUVXx
DEPRECATED!
It is planned to remove SvUVXx
from a future release of Perl. Do not use it for new code; remove it from existing code.
This is an unnecessary synonym for "SvUVX"
UV SvUVXx(SV* sv)
sv_vcatpvf
sv_vcatpvf_mg
These process their arguments like sv_vcatpvfn
called with a non-null C-style variable argument list, and append the formatted output to sv
.
They differ only in that sv_vcatpvf_mg
performs 'set' magic; sv_vcatpvf
skips 'set' magic.
Both perform 'get' magic.
They are usually accessed via their frontends "sv_catpvf"
and "sv_catpvf_mg"
.
void sv_vcatpvf(SV * const sv, const char * const pat,
va_list * const args)
sv_vcatpvfn
sv_vcatpvfn_flags
These process their arguments like vsprintf(3)
and append the formatted output to an SV. They use an array of SVs if the C-style variable argument list is missing (NULL
). Argument reordering (using format specifiers like %2$d
or %*2$d
) is supported only when using an array of SVs; using a C-style va_list
argument list with a format string that uses argument reordering will yield an exception.
When running with taint checks enabled, they indicate via maybe_tainted
if results are untrustworthy (often due to the use of locales).
They assume that pat
has the same utf8-ness as sv
. It's the caller's responsibility to ensure that this is so.
They differ in that sv_vcatpvfn_flags
has a flags
parameter in which you can set or clear the SV_GMAGIC
and/or SV_SMAGIC flags, to specify which magic to handle or not handle; whereas plain sv_vcatpvfn
always specifies both 'get' and 'set' magic.
They are usually used via one of the frontends "sv_vcatpvf
" and "sv_vcatpvf_mg
".
void sv_vcatpvfn (SV * const sv, const char * const pat,
const STRLEN patlen, va_list * const args,
SV ** const svargs, const Size_t sv_count,
bool * const maybe_tainted)
void sv_vcatpvfn_flags(SV * const sv, const char * const pat,
const STRLEN patlen, va_list * const args,
SV ** const svargs, const Size_t sv_count,
bool * const maybe_tainted,
const U32 flags)
SvVOK
Returns a boolean indicating whether the SV contains a v-string.
bool SvVOK(SV* sv)
sv_vsetpvf
sv_vsetpvf_mg
These work like "sv_vcatpvf"
but copy the text into the SV instead of appending it.
They differ only in that sv_vsetpvf_mg
performs 'set' magic; sv_vsetpvf
skips all magic.
They are usually used via their frontends, "sv_setpvf"
and "sv_setpvf_mg"
.
The UTF-8 flag is not changed by these functions.
void sv_vsetpvf(SV * const sv, const char * const pat,
va_list * const args)
sv_vsetpvfn
Works like sv_vcatpvfn
but copies the text into the SV instead of appending it.
The UTF-8 flag is not changed by this function.
Usually used via one of its frontends "sv_vsetpvf
" and "sv_vsetpvf_mg
".
void sv_vsetpvfn(SV * const sv, const char * const pat,
const STRLEN patlen, va_list * const args,
SV ** const svargs, const Size_t sv_count,
bool * const maybe_tainted)
SvVSTRING_mg
Returns the vstring magic, or NULL if none
MAGIC* SvVSTRING_mg(SV * sv)
vnewSVpvf
Like "newSVpvf"
but the arguments are an encapsulated argument list.
SV * vnewSVpvf(const char * const pat, va_list * const args)
SvTAINT
Taints an SV if tainting is enabled, and if some input to the current expression is tainted--usually a variable, but possibly also implicit inputs such as locale settings. SvTAINT
propagates that taintedness to the outputs of an expression in a pessimistic fashion; i.e., without paying attention to precisely which outputs are influenced by which inputs.
void SvTAINT(SV* sv)
SvTAINTED
Checks to see if an SV is tainted. Returns TRUE if it is, FALSE if not.
bool SvTAINTED(SV* sv)
SvTAINTED_off
Untaints an SV. Be very careful with this routine, as it short-circuits some of Perl's fundamental security features. XS module authors should not use this function unless they fully understand all the implications of unconditionally untainting the value. Untainting should be done in the standard perl fashion, via a carefully crafted regexp, rather than directly untainting variables.
void SvTAINTED_off(SV* sv)
SvTAINTED_on
Marks an SV as tainted if tainting is enabled.
void SvTAINTED_on(SV* sv)
ASCTIME_R_PROTO
This symbol encodes the prototype of asctime_r
. It is zero if d_asctime_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_asctime_r
is defined.
CTIME_R_PROTO
This symbol encodes the prototype of ctime_r
. It is zero if d_ctime_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_ctime_r
is defined.
GMTIME_MAX
This symbol contains the maximum value for the time_t
offset that the system function gmtime () accepts, and defaults to 0
GMTIME_MIN
This symbol contains the minimum value for the time_t
offset that the system function gmtime () accepts, and defaults to 0
GMTIME_R_PROTO
This symbol encodes the prototype of gmtime_r
. It is zero if d_gmtime_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_gmtime_r
is defined.
HAS_ASCTIME_R
This symbol, if defined, indicates that the asctime_r
routine is available to asctime re-entrantly.
HAS_ASCTIME64
This symbol, if defined, indicates that the asctime64
() routine is available to do the 64bit variant of asctime ()
HAS_CTIME_R
This symbol, if defined, indicates that the ctime_r
routine is available to ctime re-entrantly.
HAS_CTIME64
This symbol, if defined, indicates that the ctime64
() routine is available to do the 64bit variant of ctime ()
HAS_DIFFTIME
This symbol, if defined, indicates that the difftime
routine is available.
HAS_DIFFTIME64
This symbol, if defined, indicates that the difftime64
() routine is available to do the 64bit variant of difftime ()
HAS_FUTIMES
This symbol, if defined, indicates that the futimes
routine is available to change file descriptor time stamps with struct timevals
.
HAS_GETITIMER
This symbol, if defined, indicates that the getitimer
routine is available to return interval timers.
HAS_GETTIMEOFDAY
This symbol, if defined, indicates that the gettimeofday()
system call is available for a sub-second accuracy clock. Usually, the file sys/resource.h needs to be included (see "I_SYS_RESOURCE"
). The type "Timeval" should be used to refer to "struct timeval
".
HAS_GMTIME_R
This symbol, if defined, indicates that the gmtime_r
routine is available to gmtime re-entrantly.
HAS_GMTIME64
This symbol, if defined, indicates that the gmtime64
() routine is available to do the 64bit variant of gmtime ()
HAS_LOCALTIME_R
This symbol, if defined, indicates that the localtime_r
routine is available to localtime re-entrantly.
HAS_LOCALTIME64
This symbol, if defined, indicates that the localtime64
() routine is available to do the 64bit variant of localtime ()
HAS_MKTIME
This symbol, if defined, indicates that the mktime
routine is available.
HAS_MKTIME64
This symbol, if defined, indicates that the mktime64
() routine is available to do the 64bit variant of mktime ()
HAS_NANOSLEEP
This symbol, if defined, indicates that the nanosleep
system call is available to sleep with 1E-9 sec accuracy.
HAS_SETITIMER
This symbol, if defined, indicates that the setitimer
routine is available to set interval timers.
HAS_STRFTIME
This symbol, if defined, indicates that the strftime
routine is available to do time formatting.
HAS_TIME
This symbol, if defined, indicates that the time()
routine exists.
HAS_TIMEGM
This symbol, if defined, indicates that the timegm
routine is available to do the opposite of gmtime ()
HAS_TIMES
This symbol, if defined, indicates that the times()
routine exists. Note that this became obsolete on some systems (SUNOS
), which now use getrusage()
. It may be necessary to include sys/times.h.
HAS_TM_TM_GMTOFF
This symbol, if defined, indicates to the C program that the struct tm
has a tm_gmtoff
field.
HAS_TM_TM_ZONE
This symbol, if defined, indicates to the C program that the struct tm
has a tm_zone
field.
HAS_TZNAME
This symbol, if defined, indicates that the tzname[]
array is available to access timezone names.
HAS_USLEEP
This symbol, if defined, indicates that the usleep
routine is available to let the process sleep on a sub-second accuracy.
HAS_USLEEP_PROTO
This symbol, if defined, indicates that the system provides a prototype for the usleep()
function. Otherwise, it is up to the program to supply one. A good guess is
extern int usleep(useconds_t);
I_TIME
This symbol is always defined, and indicates to the C program that it should include time.h.
#ifdef I_TIME
#include <time.h>
#endif
I_UTIME
This symbol, if defined, indicates to the C program that it should include utime.h.
#ifdef I_UTIME
#include <utime.h>
#endif
LOCALTIME_MAX
This symbol contains the maximum value for the time_t
offset that the system function localtime () accepts, and defaults to 0
LOCALTIME_MIN
This symbol contains the minimum value for the time_t
offset that the system function localtime () accepts, and defaults to 0
LOCALTIME_R_NEEDS_TZSET
Many libc's localtime_r
implementations do not call tzset, making them differ from localtime()
, and making timezone changes using $ENV
{TZ} without explicitly calling tzset impossible. This symbol makes us call tzset before localtime_r
LOCALTIME_R_PROTO
This symbol encodes the prototype of localtime_r
. It is zero if d_localtime_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_localtime_r
is defined.
L_R_TZSET
If localtime_r()
needs tzset, it is defined in this define
mini_mktime
normalise struct tm
values without the localtime() semantics (and overhead) of mktime().
void mini_mktime(struct tm *ptm)
sv_strftime_tm
my_strftime
These implement the libc strftime().
On failure, they return NULL, and set errno
to EINVAL
.
sv_strftime_tm
is preferred, as it transparently handles the UTF-8ness of the current locale, the input fmt
, and the returned result. Only if the current LC_TIME
locale is a UTF-8 one (and use bytes
is not in effect) will the result be marked as UTF-8.
sv_strftime_tm
takes a pointer to a filled-in struct tm
parameter. It ignores the values of the wday
and yday
fields in it. The other fields give enough information to accurately calculate these values, and are used for that purpose.
The caller assumes ownership of the returned SV with a reference count of 1.
my_strftime
is kept for backwards compatibility. Knowing if its result should be considered UTF-8 or not requires significant extra logic.
The return value is a pointer to the formatted result (which MUST be arranged to be FREED BY THE CALLER). This allows this function to increase the buffer size as needed, so that the caller doesn't have to worry about that, unlike libc strftime()
.
The wday
, yday
, and isdst
parameters are ignored by my_strftime
. Daylight savings time is never considered to exist, and the values returned for the other two fields (if fmt
even calls for them) are calculated from the other parameters, without need for referencing these.
Note that both functions are always executed in the underlying LC_TIME
locale of the program, giving results based on that locale.
SV * sv_strftime_tm(SV *fmt, const struct tm *mytm)
char * my_strftime (const char *fmt, int sec, int min,
int hour, int mday, int mon, int year,
int wday, int yday, int isdst)
switch_to_global_locale
This function copies the locale state of the calling thread into the program's global locale, and converts the thread to use that global locale.
It is intended so that Perl can safely be used with C libraries that access the global locale and which can't be converted to not access it. Effectively, this means libraries that call setlocale(3)
on non-Windows systems. (For portability, it is a good idea to use it on Windows as well.)
A downside of using it is that it disables the services that Perl provides to hide locale gotchas from your code. The service you most likely will miss regards the radix character (decimal point) in floating point numbers. Code executed after this function is called can no longer just assume that this character is correct for the current circumstances.
To return to Perl control, and restart the gotcha prevention services, call "sync_locale"
. Behavior is undefined for any pure Perl code that executes while the switch is in effect.
The global locale and the per-thread locales are independent. As long as just one thread converts to the global locale, everything works smoothly. But if more than one does, they can easily interfere with each other, and races are likely. On Windows systems prior to Visual Studio 15 (at which point Microsoft fixed a bug), races can occur (even if only one thread has been converted to the global locale), but only if you use the following operations:
CRNCYSTR
and THOUSEP
CRNCYSTR
and THOUSEP
The first item is not fixable (except by upgrading to a later Visual Studio release), but it would be possible to work around the latter two items by having Perl change its algorithm for calculating these to use Windows API functions (likely GetNumberFormat
and GetCurrencyFormat
); patches welcome.
XS code should never call plain setlocale
, but should instead be converted to either call Perl_setlocale
(which is a drop-in for the system setlocale
) or use the methods given in perlcall to call POSIX::setlocale
. Either one will transparently properly handle all cases of single- vs multi-thread, POSIX 2008-supported or not.
void switch_to_global_locale()
sync_locale
This function copies the state of the program global locale into the calling thread, and converts that thread to using per-thread locales, if it wasn't already, and the platform supports them. The LC_NUMERIC locale is toggled into the standard state (using the C locale's conventions), if not within the lexical scope of use locale
.
Perl will now consider itself to have control of the locale.
Since unthreaded perls have only a global locale, this function is a no-op without threads.
This function is intended for use with C libraries that do locale manipulation. It allows Perl to accommodate the use of them. Call this function before transferring back to Perl space so that it knows what state the C code has left things in.
XS code should not manipulate the locale on its own. Instead, Perl_setlocale
can be used at any time to query or change the locale (though changing the locale is antisocial and dangerous on multi-threaded systems that don't have multi-thread safe locale operations. (See "Multi-threaded operation" in perllocale).
Using the libc setlocale(3)
function should be avoided. Nevertheless, certain non-Perl libraries called from XS, do call it, and their behavior may not be able to be changed. This function, along with "switch_to_global_locale"
, can be used to get seamless behavior in these circumstances, as long as only one thread is involved.
If the library has an option to turn off its locale manipulation, doing that is preferable to using this mechanism. Gtk
is such a library.
The return value is a boolean: TRUE if the global locale at the time of call was in effect for the caller; and FALSE if a per-thread locale was in effect.
bool sync_locale()
DB_Hash_t
This symbol contains the type of the prefix structure element in the db.h header file. In older versions of DB, it was int, while in newer ones it is size_t
.
DB_Prefix_t
This symbol contains the type of the prefix structure element in the db.h header file. In older versions of DB, it was int, while in newer ones it is u_int32_t
.
Direntry_t
This symbol is set to 'struct direct
' or 'struct dirent
' depending on whether dirent is available or not. You should use this pseudo type to portably declare your directory entries.
Fpos_t
This symbol holds the type used to declare file positions in libc. It can be fpos_t
, long, uint, etc... It may be necessary to include sys/types.h to get any typedef'ed information.
Free_t
This variable contains the return type of free()
. It is usually void, but occasionally int.
Gid_t
This symbol holds the return type of getgid()
and the type of argument to setrgid()
and related functions. Typically, it is the type of group ids in the kernel. It can be int, ushort, gid_t
, etc... It may be necessary to include sys/types.h to get any typedef'ed information.
Gid_t_f
This symbol defines the format string used for printing a Gid_t
.
Gid_t_sign
This symbol holds the signedness of a Gid_t
. 1 for unsigned, -1 for signed.
Gid_t_size
This symbol holds the size of a Gid_t
in bytes.
Groups_t
This symbol holds the type used for the second argument to getgroups()
and setgroups()
. Usually, this is the same as gidtype (gid_t
) , but sometimes it isn't. It can be int, ushort, gid_t
, etc... It may be necessary to include sys/types.h to get any typedef'ed information. This is only required if you have getgroups()
or setgroups()
..
Malloc_t
This symbol is the type of pointer returned by malloc and realloc.
Mmap_t
This symbol holds the return type of the mmap()
system call (and simultaneously the type of the first argument). Usually set to 'void *' or 'caddr_t
'.
Mode_t
This symbol holds the type used to declare file modes for systems calls. It is usually mode_t
, but may be int or unsigned short. It may be necessary to include sys/types.h to get any typedef'ed information.
Netdb_hlen_t
This symbol holds the type used for the 2nd argument to gethostbyaddr()
.
Netdb_host_t
This symbol holds the type used for the 1st argument to gethostbyaddr()
.
Netdb_name_t
This symbol holds the type used for the argument to gethostbyname()
.
Netdb_net_t
This symbol holds the type used for the 1st argument to getnetbyaddr()
.
Off_t
This symbol holds the type used to declare offsets in the kernel. It can be int, long, off_t
, etc... It may be necessary to include sys/types.h to get any typedef'ed information.
Off_t_size
This symbol holds the number of bytes used by the Off_t
.
Pid_t
This symbol holds the type used to declare process ids in the kernel. It can be int, uint, pid_t
, etc... It may be necessary to include sys/types.h to get any typedef'ed information.
Rand_seed_t
This symbol defines the type of the argument of the random seed function.
Select_fd_set_t
This symbol holds the type used for the 2nd, 3rd, and 4th arguments to select. Usually, this is 'fd_set
*', if HAS_FD_SET
is defined, and 'int *' otherwise. This is only useful if you have select()
, of course.
Shmat_t
This symbol holds the return type of the shmat()
system call. Usually set to 'void *' or 'char *'.
Signal_t
This symbol's value is either "void" or "int", corresponding to the appropriate return type of a signal handler. Thus, you can declare a signal handler using "Signal_t
(*handler)()", and define the handler using "Signal_t
handler(sig)
".
Size_t
This symbol holds the type used to declare length parameters for string functions. It is usually size_t
, but may be unsigned long, int, etc. It may be necessary to include sys/types.h to get any typedef'ed information.
Size_t_size
This symbol holds the size of a Size_t
in bytes.
Sock_size_t
This symbol holds the type used for the size argument of various socket calls (just the base type, not the pointer-to).
SSize_t
This symbol holds the type used by functions that return a count of bytes or an error condition. It must be a signed type. It is usually ssize_t
, but may be long or int, etc. It may be necessary to include sys/types.h or unistd.h to get any typedef'ed information. We will pick a type such that sizeof(SSize_t)
== sizeof(Size_t)
.
Time_t
This symbol holds the type returned by time()
. It can be long, or time_t
on BSD
sites (in which case sys/types.h should be included).
Uid_t
This symbol holds the type used to declare user ids in the kernel. It can be int, ushort, uid_t
, etc... It may be necessary to include sys/types.h to get any typedef'ed information.
Uid_t_f
This symbol defines the format string used for printing a Uid_t
.
Uid_t_sign
This symbol holds the signedness of a Uid_t
. 1 for unsigned, -1 for signed.
Uid_t_size
This symbol holds the size of a Uid_t
in bytes.
"Unicode Support" in perlguts has an introduction to this API.
See also "Character classification"
, "Character case changing"
, and "String Handling"
. Various functions outside this section also work specially with Unicode. Search for the string "utf8" in this document.
BOM_UTF8
This is a macro that evaluates to a string constant of the UTF-8 bytes that define the Unicode BYTE ORDER MARK (U+FEFF) for the platform that perl is compiled on. This allows code to use a mnemonic for this character that works on both ASCII and EBCDIC platforms. sizeof(BOM_UTF8) - 1
can be used to get its length in bytes.
bytes_cmp_utf8
Compares the sequence of characters (stored as octets) in b
, blen
with the sequence of characters (stored as UTF-8) in u
, ulen
. Returns 0 if they are equal, -1 or -2 if the first string is less than the second string, +1 or +2 if the first string is greater than the second string.
-1 or +1 is returned if the shorter string was identical to the start of the longer string. -2 or +2 is returned if there was a difference between characters within the strings.
int bytes_cmp_utf8(const U8 *b, STRLEN blen, const U8 *u,
STRLEN ulen)
bytes_from_utf8
NOTE: bytes_from_utf8
is experimental and may change or be removed without notice.
Converts a potentially UTF-8 encoded string s
of length *lenp
into native byte encoding. On input, the boolean *is_utf8p
gives whether or not s
is actually encoded in UTF-8.
Unlike "utf8_to_bytes" but like "bytes_to_utf8", this is non-destructive of the input string.
Do nothing if *is_utf8p
is 0, or if there are code points in the string not expressible in native byte encoding. In these cases, *is_utf8p
and *lenp
are unchanged, and the return value is the original s
.
Otherwise, *is_utf8p
is set to 0, and the return value is a pointer to a newly created string containing a downgraded copy of s
, and whose length is returned in *lenp
, updated. The new string is NUL
-terminated. The caller is responsible for arranging for the memory used by this string to get freed.
Upon successful return, the number of variants in the string can be computed by having saved the value of *lenp
before the call, and subtracting the after-call value of *lenp
from it.
U8 * bytes_from_utf8(const U8 *s, STRLEN *lenp, bool *is_utf8p)
bytes_to_utf8
NOTE: bytes_to_utf8
is experimental and may change or be removed without notice.
Converts a string s
of length *lenp
bytes from the native encoding into UTF-8. Returns a pointer to the newly-created string, and sets *lenp
to reflect the new length in bytes. The caller is responsible for arranging for the memory used by this string to get freed.
Upon successful return, the number of variants in the string can be computed by having saved the value of *lenp
before the call, and subtracting it from the after-call value of *lenp
.
A NUL
character will be written after the end of the string.
If you want to convert to UTF-8 from encodings other than the native (Latin1 or EBCD