windows-nt/Source/XPSP1/NT/enduser/speech/lib/perl/dirhandle.pm
2020-09-26 16:20:57 +08:00

73 lines
1.3 KiB
Perl

package DirHandle;
=head1 NAME
DirHandle - supply object methods for directory handles
=head1 SYNOPSIS
use DirHandle;
$d = new DirHandle ".";
if (defined $d) {
while (defined($_ = $d->read)) { something($_); }
$d->rewind;
while (defined($_ = $d->read)) { something_else($_); }
undef $d;
}
=head1 DESCRIPTION
The C<DirHandle> method provide an alternative interface to the
opendir(), closedir(), readdir(), and rewinddir() functions.
The only objective benefit to using C<DirHandle> is that it avoids
namespace pollution by creating globs to hold directory handles.
=cut
require 5.000;
use Carp;
use Symbol;
sub new {
@_ >= 1 && @_ <= 2 or croak 'usage: new DirHandle [DIRNAME]';
my $class = shift;
my $dh = gensym;
if (@_) {
DirHandle::open($dh, $_[0])
or return undef;
}
bless $dh, $class;
}
sub DESTROY {
my ($dh) = @_;
closedir($dh);
}
sub open {
@_ == 2 or croak 'usage: $dh->open(DIRNAME)';
my ($dh, $dirname) = @_;
opendir($dh, $dirname);
}
sub close {
@_ == 1 or croak 'usage: $dh->close()';
my ($dh) = @_;
closedir($dh);
}
sub read {
@_ == 1 or croak 'usage: $dh->read()';
my ($dh) = @_;
readdir($dh);
}
sub rewind {
@_ == 1 or croak 'usage: $dh->rewind()';
my ($dh) = @_;
rewinddir($dh);
}
1;