homedir.pm

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2015 (maintaining the general Perl convention of a 10 year support period
for legacy APIs potentially or actually in common use).

=head2 Platform Neutrality

In the Unix world, many different types of data can be mixed together
in your home directory (although on some Unix platforms this is no longer
the case, particularly for "desktop"-oriented platforms).

On some non-Unix platforms, seperate directories are allocated for
different types of data and have been for a long time.

When writing applications on top of B<File::HomeDir>, you should thus
always try to use the most specific method you can. User documents should
be saved in C<my_documents>, data that supports an application but isn't
normally editing by the user directory should go into C<my_data>.

On platforms that do not make any distinction, all these different
methods will harmlessly degrade to the main home directory, but on
platforms that care B<File::HomeDir> will always try to Do The Right
Thing(tm).

=head1 METHODS

Two types of methods are provided. The C<my_method> series of methods for
finding resources for the current user, and the C<users_method> (read as
"user's method") series for finding resources for arbitrary users.

This split is necesary, as on most platforms it is B<much> easier to find
information about the current user compared to other users, and indeed
on a number you cannot find out information such as C<users_desktop> at
all, due to security restrictions.

All methods will double check (using a C<-d> test) that a directory
actually exists before returning it, so you may trust in the values
that are returned (subject to the usual caveats of race conditions of
directories being deleted at the moment between a directory being returned
and you using it).

However, because in some cases platforms may not support the concept of home
directories at all, any method may return C<undef> (both in scalar and list
context) to indicate that there is no matching directory on the system.

For example, most untrusted 'nobody'-type users do not have a home
directory. So any modules that are used in a CGI application that
at some level of recursion use your code, will result in calls to
File::HomeDir returning undef, even for a basic home() call.

=head2 my_home

The C<my_home> method takes no arguments and returns the main home/profile
directory for the current user.

If the distinction is important to you, the term "current" refers to the
real user, and not the effective user.

This is also the case for all of the other "my" methods.

Returns the directory path as a string, C<undef> if the current user
does not have a home directory, or dies on error.

=head2 my_desktop

The C<my_desktop> method takes no arguments and returns the "desktop"
directory for the current user.

Due to the diversity and complexity of implementions required to deal with
implementing the required functionality fully and completely, for the moment
C<my_desktop> is B<not> going to be implemented.

That said, I am extremely interested in code to implement C<my_desktop> on
Unix, as long as it is capable of dealing (as the Windows implementation
does) with internationalisation. It should also avoid false positive
results by making sure it only returns the appropriate directories for the
appropriate platforms.

Returns the directory path as a string, C<undef> if the current user
does not have a desktop directory, or dies on error.

=head2 my_documents

The C<my_documents> method takes no arguments and returns the directory (for
the current user) where the user's documents are stored.

Returns the directory path as a string, C<undef> if the current user
does not have a documents directory, or dies on error.

=head2 my_music

The C<my_music> method takes no arguments and returns the directory
where the current user's music is stored.

No bias is made to any particular music type or music program, rather the
concept of a directory to hold the user's music is made at the level of the
underlying operating system or (at least) desktop environment.

Returns the directory path as a string, C<undef> if the current user
does not have a suitable directory, or dies on error.

=head2 my_pictures

The C<my_pictures> method takes no arguments and returns the directory
where the current user's pictures are stored.

No bias is made to any particular picture type or picture program, rather the
concept of a directory to hold the user's pictures is made at the level of the
underlying operating system or (at least) desktop environment.

Returns the directory path as a string, C<undef> if the current user
does not have a suitable directory, or dies on error.

=head2 my_videos

The C<my_videos> method takes no arguments and returns the directory
where the current user's videos are stored.

No bias is made to any particular video type or video program, rather the
concept of a directory to hold the user's videos is made at the level of the
underlying operating system or (at least) desktop environment.

Returns the directory path as a string, C<undef> if the current user
does not have a suitable directory, or dies on error.

=head2 my_data

The C<my_data> takes no arguments and returns the directory where
local applications should stored their internal data for the current
user.

Generally an application would create a subdirectory such as C<.foo>,
beneath this directory, and store its data there. By creating your
directory this way, you get an accurate result on the maximum number
of platforms.

For example, on Unix you get C<~/.foo> and on Win32 you get
C<~/Local Settings/Application Data/.foo>

Returns the directory path as a string, C<undef> if the current user
does not have a data directory, or dies on error.

=head2 users_home

  $home = File::HomeDir->users_home('foo');

The C<users_home> method takes a single param and is used to locate the
parent home/profile directory for an identified user on the system.

While most of the time this identifier would be some form of user name,
it is permitted to vary per-platform to support user ids or UUIDs as
applicable for that platform.

Returns the directory path as a string, C<undef> if that user
does not have a home directory, or dies on error.

=head2 users_documents

  $docs = File::HomeDir->users_documents('foo');

Returns the directory path as a string, C<undef> if that user
does not have a documents directory, or dies on error.

=head2 users_data

  $data = File::HomeDir->users_data('foo');

Returns the directory path as a string, C<undef> if that user
does not have a data directory, or dies on error.

=head1 FUNCTIONS

=head2 home

  use File::HomeDir;
  $home = home();
  $home = home('foo');
  $home = File::HomeDir::home();
  $home = File::HomeDir::home('foo');

The C<home> function is exported by default and is provided for
compatibility with legacy applications. In new applications, you should
use the newer method-based interface above.

Returns the directory path to a named user's home/profile directory.

If provided no param, returns the directory path to the current user's
home/profile directory.

=head1 TIED INTERFACE

=head2 %~

  $home = $~{""};
  $home = $~{undef};
  $home = $~{$user};
  $home = $~{username};
  print "... $~{''} ...";
  print "... $~{$user} ...";
  print "... $~{username} ...";

This calls C<home($user)> or C<home('username')> -- except that if you
ask for C<$~{some_user}> and there is no such user, it will die.

Note that this is especially useful in double-quotish strings, like:

     print "Jojo's .newsrc is ", -s "$~{jojo}/.newsrc", "b long!\n";
      # (helpfully dies if there is no user 'jojo')

If you want to avoid the fatal errors, first test the value of
C<home('jojo')>, which will return undef (instead of dying) in case of
there being no such user.

Note, however, that if the hash key is "" or undef (whether thru being
a literal "", or a scalar whose value is empty-string or undef), then
this returns zero-argument C<home()>, i.e., your home directory:

Further, please note that because the %~ hash compulsorily modifies
a hash outside of it's namespace, and presents an overly simplistic
approach to home directories, it is likely to ultimately be removed.

The interface is currently expected to be formally deprecated from 2010
(but no earlier) and removed from 2015 (but no earlier). If very heavy
use is found in the wild, these plans may be pushed back.

=head1 TO DO

=over 4

=item * Become generally clearer on situations in which a user might not
have a particular resource.

=item * Merge remaining edge case code in File::HomeDir::Win32

=item * Add more granularity to Unix, and add support to VMS and other
esoteric platforms, so we can consider going core.

=item * Add consistent support for users_* methods 

=back

=head1 SUPPORT

This module is stored in an Open Repository at the following address.

L<http://svn.ali.as/cpan/trunk/File-HomeDir>

Write access to the repository is made available automatically to any
published CPAN author, and to most other volunteers on request.

If you are able to submit your bug report in the form of new (failing)
unit tests, or can apply your fix directly instead of submitting a patch,
you are B<strongly> encouraged to do so as the author currently maintains
over 100 modules and it can take some time to deal with non-Critical bug
reports or patches.

This will guarantee that your issue will be addressed in the next
release of the module.

If you cannot provide a direct test or fix, or don't have time to do so,
then regular bug reports are still accepted and appreciated via the CPAN
bug tracker.

L<http://rt.cpan.org/NoAuth/ReportBug.html?Queue=File-HomeDir>

For other issues, for commercial enhancement or support, or to have your
write access enabled for the repository, contact the author at the email
address above.

=head1 ACKNOWLEDGEMENTS

The biggest acknowledgement must go to Chris Nandor, who wielded his
legendary Mac-fu and turned my initial fairly ordinary Darwin
implementation into something that actually worked properly everywhere,
and then donated a Mac OS X license to allow it to be maintained properly.

=head1 AUTHORS

Adam Kennedy E<lt>[e-mail]<gt>

Sean M. Burke E<lt>[e-mail]<gt>

Chris Nandor E<lt>[e-mail]<gt>

Stephen Steneker E<lt>[e-mail]<gt>

=head1 SEE ALSO

L<File::ShareDir>, L<File::HomeDir::Win32> (legacy)

=head1 COPYRIGHT

Copyright 2005, 2006 Adam Kennedy.

Some parts copyright 2000 Sean M. Burke.

Some parts copyright 2006 Chris Nandor.

Some parts copyright 2006 Stephen Steneker.

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

The full text of the license can be found in the
LICENSE file included with this module.

=cut