IO::File(3pm) Perl Programmers Reference Guide IO::File(3pm)
NAME
IO::File - supply object methods for filehandles
SYNOPSIS
use IO::File;
my $fh = IO::File->new();
if ($fh->open("< file")) {
print <$fh>;
$fh->close;
}
my $fh = IO::File->new("> file");
if (defined $fh) {
print $fh "bar\n";
$fh->close;
}
my $fh = IO::File->new("file", "r");
if (defined $fh) {
print <$fh>;
undef $fh; # automatically closes the file
}
my $fh = IO::File->new("file", O_WRONLY|O_APPEND);
if (defined $fh) {
print $fh "corge\n";
my $pos = $fh->getpos;
$fh->setpos($pos);
undef $fh; # automatically closes the file
}
autoflush STDOUT 1;
DESCRIPTION
"IO::File" inherits from "IO::Handle" and "IO::Seekable". It extends
these classes with methods that are specific to file handles.
CONSTRUCTOR
new ( FILENAME [,MODE [,PERMS]] )
Creates an "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.
new_tmpfile
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.
METHODS
open( FILENAME [,MODE [,PERMS]] )
open( FILENAME, IOLAYERS )
"open" accepts one, two or three parameters. With one parameter,
it is just a front end for the built-in "open" function. With two
or three 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 an ANSI C fopen() mode string ("w", "r+", etc.), it uses the
basic Perl "open" operator (but protects any special characters).
If "IO::File::open" is given a numeric mode, it passes that mode
and the optional permissions value to the Perl "sysopen" operator.
The permissions default to 0666.
If "IO::File::open" is given a mode that includes the ":"
character, it passes all the three arguments to the three-argument
"open" operator.
For convenience, "IO::File" exports the O_XXX constants from the
Fcntl module, if this module is available.
binmode( [LAYER] )
"binmode" sets "binmode" on the underlying "IO" object, as
documented in "perldoc -f binmode".
"binmode" accepts one optional parameter, which is the layer to be
passed on to the "binmode" call.
NOTE
Some operating systems may perform IO::File::new() or IO::File::open()
on a directory without errors. This behavior is not portable and not
suggested for use. Using opendir() and readdir() or "IO::Dir" are
suggested instead.
SEE ALSO
perlfunc(1), "I/O Operators" in perlop(1), IO::Handle(3),
IO::Seekable(3), IO::Dir(3)
HISTORY
Derived from FileHandle.pm by Graham Barr <gbarr@pobox.com>.
perl v5.38.2 2023-11-28 IO::File(3pm)
perl 5.38.2 - Generated Sat Dec 7 08:53:10 CST 2024