kenahoo / Path-Class

Cross-platform path specification manipulation
http://search.cpan.org/dist/Path-Class/
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=head1 NAME

Path::Class - Cross-platform path specification manipulation for Perl

=head1 SYNOPSIS

use Path::Class;

my $dir = dir('foo', 'bar'); # Path::Class::Dir object my $file = file('bob', 'file.txt'); # Path::Class::File object

Stringifies to 'foo/bar' on Unix, 'foo\bar' on Windows, etc.

print "dir: $dir\n";

Stringifies to 'bob/file.txt' on Unix, 'bob\file.txt' on Windows

print "file: $file\n";

my $subdir = $dir->subdir('baz'); # foo/bar/baz my $parent = $subdir->parent; # foo/bar my $parent2 = $parent->parent; # foo

my $dir2 = $file->dir; # bob

Work with foreign paths

use Path::Class qw(foreign_file foreign_dir); my $file = foreign_file('Mac', ':foo:file.txt'); print $file->dir; # :foo: print $file->as_foreign('Win32'); # foo\file.txt

Interact with the underlying filesystem:

$dir_handle is an IO::Dir object

my $dir_handle = $dir->open or die "Can't read $dir: $!";

$file_handle is an IO::File object

my $file_handle = $file->open($mode) or die "Can't read $file: $!";

=head1 DESCRIPTION

C is a module for manipulation of file and directory specifications (strings describing their locations, like C<'/home/ken/foo.txt'> or C<'C:\Windows\Foo.txt'>) in a cross-platform manner. It supports pretty much every platform Perl runs on, including Unix, Windows, Mac, VMS, Epoc, Cygwin, OS/2, and NetWare.

The well-known module L also provides this service, but it's sort of awkward to use well, so people sometimes avoid it, or use it in a way that won't actually work properly on platforms significantly different than the ones they've tested their code on.

In fact, C uses C internally, wrapping all the unsightly details so you can concentrate on your application code. Whereas C provides functions for some common path manipulations, C provides an object-oriented model of the world of path specifications and their underlying semantics. C doesn't create any objects, and its classes represent the different ways in which paths must be manipulated on various platforms (not a very intuitive concept). C creates objects representing files and directories, and provides methods that relate them to each other. For instance, the following C code:

my $absolute = File::Spec->file_name_is_absolute( File::Spec->catfile( @dirs, $file ) );

can be written using C as

my $absolute = Path::Class::File->new( @dirs, $file )->is_absolute;

or even as

my $absolute = file( @dirs, $file )->is_absolute;

Similar readability improvements should happen all over the place when using C.

Using C can help solve real problems in your code too - for instance, how many people actually take the "volume" (like C on Windows) into account when writing C-using code? I thought not. But if you use C, your file and directory objects will know what volumes they refer to and do the right thing.

The guts of the C code live in the L and L modules, so please see those modules' documentation for more details about how to use them.

=head2 EXPORT

The following functions are exported by default.

=over 4

=item file

A synonym for C<< Path::Class::File->new >>.

=item dir

A synonym for C<< Path::Class::Dir->new >>.

=back

If you would like to prevent their export, you may explicitly pass an empty list to perl's C, i.e. C<use Path::Class ()>.

The following are exported only on demand.

=over 4

=item foreign_file

A synonym for C<< Path::Class::File->new_foreign >>.

=item foreign_dir

A synonym for C<< Path::Class::Dir->new_foreign >>.

=item tempdir

Create a new Path::Class::Dir instance pointed to temporary directory.

my $temp = Path::Class::tempdir(CLEANUP => 1);

A synonym for C<< Path::Class::Dir->new(File::Temp::tempdir(@_)) >>.

=back

=head1 Notes on Cross-Platform Compatibility

Although it is much easier to write cross-platform-friendly code with this module than with C, there are still some issues to be aware of.

=over 4

=item *

On some platforms, notably VMS and some older versions of DOS (I think), all filenames must have an extension. Thus if you create a file called F<foo/bar> and then ask for a list of files in the directory F, you may find a file called F instead of the F you were expecting. Thus it might be a good idea to use an extension in the first place.

=back

=head1 AUTHOR

Ken Williams, KWILLIAMS@cpan.org

=head1 COPYRIGHT

Copyright (c) Ken Williams. All rights reserved.

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

=head1 SEE ALSO

L, L, L

=cut