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IO::File - supply object methods for filehandles


use IO::File;

$fh = new IO::File;
if ($fh->open("< file")) {
    print <$fh>;

$fh = new IO::File "> file";
if (defined $fh) {
    print $fh "bar\n";

$fh = new IO::File "file", "r";
if (defined $fh) {
    print <$fh>;
    undef $fh;       # automatically closes the file

$fh = new IO::File "file", O_WRONLY|O_APPEND;
if (defined $fh) {
    print $fh "corge\n";

    $pos = $fh->getpos;

    undef $fh;       # automatically closes the file

autoflush STDOUT 1;


IO::File inherits from IO::Handle and IO::Seekable. It extends these classes with methods that are specific to file handles.


new ([ ARGS ] )

Creates a IO::File. If it receives any parameters, they are passed to the method open; if the open fails, the object is destroyed. Otherwise, it is returned to the caller.


Creates an IO::File opened for read/write on a newly created temporary file. On systems where this is possible, the temporary file is anonymous (i.e. it is unlinked after creation, but held open). If the temporary file cannot be created or opened, the IO::File object is destroyed. Otherwise, it is returned to the caller.



open accepts one, two or three parameters. With one parameter, it is just a front end for the built-in open function. With two parameters, the first parameter is a filename that may include whitespace or other special characters, and the second parameter is the open mode, optionally followed by a file permission value.

If IO::File::open receives a Perl mode string (">", "+<", etc.) or a POSIX fopen() mode string ("w", "r+", etc.), it uses the basic Perl open operator.

If IO::File::open is given a numeric mode, it passes that mode and the optional permissions value to the Perl sysopen operator. For convenience, IO::File::import tries to import the O_XXX constants from the Fcntl module. If dynamic loading is not available, this may fail, but the rest of IO::File will still work.


perlfunc, "I/O Operators" in perlop, IO::Handle IO::Seekable


Derived from by Graham Barr <>.