perlutil - utilities packaged with the Perl distribution
Along with the Perl interpreter itself, the Perl distribution installs a range of utilities on your system. There are also several utilities which are used by the Perl distribution itself as part of the install process. This document exists to list all of these utilities, explain what they are for and provide pointers to each module's documentation, if appropriate.
The main interface to Perl's documentation is perldoc, although if you're reading this, it's more than likely that you've already found it. perldoc will extract and format the documentation from any file in the current directory, any Perl module installed on the system, or any of the standard documentation pages, such as this one. Use perldoc <name> to get information on any of the utilities described in this document.
If it's run from a terminal, perldoc will usually call pod2man to translate POD (Plain Old Documentation - see perlpod for an explanation) into a manpage, and then run man to display it; if man isn't available, pod2text will be used instead and the output piped through your favourite pager.
As well as these two, there are two other converters: pod2html will produce HTML pages from POD, and pod2latex, which produces LaTeX files.
If you just want to know how to use the utilities described here, pod2usage will just extract the "USAGE" section; some of the utilities will automatically call pod2usage on themselves when you call them with -help.
pod2usage is a special case of podselect, a utility to extract named sections from documents written in POD. For instance, while utilities have "USAGE" sections, Perl modules usually have "SYNOPSIS" sections: podselect -s "SYNOPSIS" ... will extract this section for a given file.
If you're writing your own documentation in POD, the podchecker utility will look for errors in your markup.
splain is an interface to perldiag - paste in your error message to it, and it'll explain it for you.
The roffitall utility is not installed on your system but lives in the pod/ directory of your Perl source kit; it converts all the documentation from the distribution to *roff format, and produces a typeset PostScript or text file of the whole lot.
To help you convert legacy programs to Perl, we've included three conversion filters:
a2p converts awk scripts to Perl programs; for example, a2p -F: on the simple awk script {print $2} will produce a Perl program based around this code:
while (<>) {
($Fld1,$Fld2) = split(/[:\n]/, $_, 9999);
print $Fld2;
}Similarly, s2p converts sed scripts to Perl programs. s2p run on s/foo/bar will produce a Perl program based around this:
while (<>) {
chomp;
s/foo/bar/g;
print if $printit;
}Finally, find2perl translates find commands to Perl equivalents which use the File::Find module. As an example, find2perl . -user root -perm 4000 -print produces the following callback subroutine for File::Find:
sub wanted {
my ($dev,$ino,$mode,$nlink,$uid,$gid);
(($dev,$ino,$mode,$nlink,$uid,$gid) = lstat($_)) &&
$uid == $uid{'root'}) &&
(($mode & 0777) == 04000);
print("$name\n");
}As well as these filters for converting other languages, the pl2pm utility will help you convert old-style Perl 4 libraries to new-style Perl5 modules.
There are a set of utilities which help you in developing Perl programs, and in particular, extending Perl with C.
perlbug is the recommended way to report bugs in the perl interpreter itself or any of the standard library modules back to the developers; please read through the documentation for perlbug thoroughly before using it to submit a bug report.
Back before Perl had the XS system for connecting with C libraries, programmers used to get library constants by reading through the C header files. You may still see require 'syscall.ph' or similar around - the .ph file should be created by running h2ph on the corresponding .h file. See the h2ph documentation for more on how to convert a whole bunch of header files at once.
c2ph and pstruct, which are actually the same program but behave differently depending on how they are called, provide another way of getting at C with Perl - they'll convert C structures and union declarations to Perl code. This is deprecated in favour of h2xs these days.
h2xs converts C header files into XS modules, and will try and write as much glue between C libraries and Perl modules as it can. It's also very useful for creating skeletons of pure Perl modules.
Perl comes with a profiler, the Devel::DProf module. The dprofpp utility analyzes the output of this profiler and tells you which subroutines are taking up the most run time. See Devel::DProf for more information.
perlcc is the interface to the experimental Perl compiler suite.
perldoc, pod2man, perlpod, pod2html, pod2usage, podselect, podchecker, splain, perldiag, roffitall, a2p, s2p, find2perl, File::Find, pl2pm, perlbug, h2ph, c2ph, h2xs, dprofpp, Devel::DProf, perlcc