IO::File - supply object methods for filehandles |
IO::File - supply object methods for filehandles
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;
IO::File
inherits from IO::Handle
and IO::Seekable
. It extends
these classes with methods that are specific to file handles.
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.
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 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
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.
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.
the perlfunc manpage, I/O Operators in the perlop manpage, the IO::Handle manpage, the IO::Seekable manpage, the IO::Dir manpage
Derived from FileHandle.pm by Graham Barr <gbarr@pobox.com>.
IO::File - supply object methods for filehandles |