windows-nt/Source/XPSP1/NT/tools/x86/perl/lib/io/seekable.pm
2020-09-26 16:20:57 +08:00

69 lines
1.4 KiB
Perl

#
package IO::Seekable;
=head1 NAME
IO::Seekable - supply seek based methods for I/O objects
=head1 SYNOPSIS
use IO::Seekable;
package IO::Something;
@ISA = qw(IO::Seekable);
=head1 DESCRIPTION
C<IO::Seekable> does not have a constructor of its own as it is intended to
be inherited by other C<IO::Handle> based objects. It provides methods
which allow seeking of the file descriptors.
If the C functions fgetpos() and fsetpos() are available, then
C<IO::File::getpos> returns an opaque value that represents the
current position of the IO::File, and C<IO::File::setpos> uses
that value to return to a previously visited position.
See L<perlfunc> for complete descriptions of each of the following
supported C<IO::Seekable> methods, which are just front ends for the
corresponding built-in functions:
seek
tell
=head1 SEE ALSO
L<perlfunc>,
L<perlop/"I/O Operators">,
L<IO::Handle>
L<IO::File>
=head1 HISTORY
Derived from FileHandle.pm by Graham Barr E<lt>bodg@tiuk.ti.comE<gt>
=cut
require 5.000;
use Carp;
use strict;
use vars qw($VERSION @EXPORT @ISA);
use IO::Handle qw(SEEK_SET SEEK_CUR SEEK_END);
require Exporter;
@EXPORT = qw(SEEK_SET SEEK_CUR SEEK_END);
@ISA = qw(Exporter);
$VERSION = "1.06";
sub seek {
@_ == 3 or croak 'usage: $fh->seek(POS, WHENCE)';
seek($_[0], $_[1], $_[2]);
}
sub tell {
@_ == 1 or croak 'usage: $fh->tell()';
tell($_[0]);
}
1;