NAME¶
IO::File - supply object methods for filehandles
SYNOPSIS¶
use IO::File;
$fh = IO::File->new();
if ($fh->open("< file")) {
print <$fh>;
$fh->close;
}
$fh = IO::File->new("> file");
if (defined $fh) {
print $fh "bar\n";
$fh->close;
}
$fh = IO::File->new("file", "r");
if (defined $fh) {
print <$fh>;
undef $fh; # automatically closes the file
}
$fh = IO::File->new("file", O_WRONLY|O_APPEND);
if (defined $fh) {
print $fh "corge\n";
$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, "I/O Operators" in perlop, IO::Handle, IO::Seekable, IO::Dir
HISTORY¶
Derived from FileHandle.pm by Graham Barr <
gbarr@pobox.com>.