File::HomeDir(3) User Contributed Perl Documentation File::HomeDir(3)NAMEFile::HomeDir - Find your home and other directories, on any platform
SYNOPSIS
use File::HomeDir;
# Modern Interface (Current User)
$home = File::HomeDir->my_home;
$desktop = File::HomeDir->my_desktop;
$docs = File::HomeDir->my_documents;
$music = File::HomeDir->my_music;
$pics = File::HomeDir->my_pictures;
$videos = File::HomeDir->my_videos;
$data = File::HomeDir->my_data;
# Modern Interface (Other Users)
$home = File::HomeDir->users_home('foo');
$desktop = File::HomeDir->users_desktop('foo');
$docs = File::HomeDir->users_documents('foo');
$music = File::HomeDir->users_music('foo');
$pics = File::HomeDir->users_pictures('foo');
$video = File::HomeDir->users_videos('foo');
$data = File::HomeDir->users_data('foo');
# Legacy Interfaces
print "My dir is ", home(), " and root's is ", home('root'), "\n";
print "My dir is $~{''} and root's is $~{root}\n";
# These both print the same thing, something like:
# "My dir is /home/user/mojo and root's is /"
DESCRIPTIONFile::HomeDir is a module for dealing with issues relating to the
location of directories that are "owned" by a user, primarily your
user, and to solve these issues consistently across a wide variety of
platforms.
Thus, a single API is presented that can find your resources on any
platform.
This module provides two main interfaces.
The first is a modern File::Spec-style interface with a consistent OO
API and different implementation modules to support various platforms.
You are strongly recommended to use this interface.
The second interface is for legacy support of the original 0.07
interface that exported a "home()" function by default and tied the
"%~" variable.
It is generally not recommended that you use this interface, but due to
back-compatibility reasons they will remain supported until at least
2010.
After this date, the home() function will remain, but we will consider
deprecating the (namespace-polluting) "%~" tied hash, to be removed by
2015 (maintaining the general Perl convention of a 10 year support
period for legacy APIs potentially or actually in common use).
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 File::HomeDir, you should thus
always try to use the most specific method you can. User documents
should be saved in "my_documents", data that supports an application
but isn't normally editing by the user directory should go into
"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 File::HomeDir will always try to Do The Right
Thing(tm).
METHODS
Two types of methods are provided. The "my_method" series of methods
for finding resources for the current user, and the "users_method"
(read as "user's method") series for finding resources for arbitrary
users.
This split is necesary, as on most platforms it is 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 "users_desktop" at
all, due to security restrictions.
All methods will double check (using a "-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 "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.
my_home
The "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, "undef" if the current user
does not have a home directory, or dies on error.
my_desktop
The "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 "my_desktop" is not going to be implemented.
That said, I am extremely interested in code to implement "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, "undef" if the current user
does not have a desktop directory, or dies on error.
my_documents
The "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, "undef" if the current user
does not have a documents directory, or dies on error.
my_music
The "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, "undef" if the current user
does not have a suitable directory, or dies on error.
my_pictures
The "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, "undef" if the current user
does not have a suitable directory, or dies on error.
my_videos
The "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, "undef" if the current user
does not have a suitable directory, or dies on error.
my_data
The "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 ".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 "~/.foo" and on Win32 you get "~/Local
Settings/Application Data/.foo"
Returns the directory path as a string, "undef" if the current user
does not have a data directory, or dies on error.
users_home
$home = File::HomeDir->users_home('foo');
The "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, "undef" if that user does not
have a home directory, or dies on error.
users_documents
$docs = File::HomeDir->users_documents('foo');
Returns the directory path as a string, "undef" if that user does not
have a documents directory, or dies on error.
users_data
$data = File::HomeDir->users_data('foo');
Returns the directory path as a string, "undef" if that user does not
have a data directory, or dies on error.
FUNCTIONS
home
use File::HomeDir;
$home = home();
$home = home('foo');
$home = File::HomeDir::home();
$home = File::HomeDir::home('foo');
The "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.
TIED INTERFACE
%~
$home = $~{""};
$home = $~{undef};
$home = $~{$user};
$home = $~{username};
print "... $~{''} ...";
print "... $~{$user} ...";
print "... $~{username} ...";
This calls "home($user)" or "home('username')" -- except that if you
ask for $~{some_user} and there is no such user, it will die.
Note that this is especially useful in double-quotish strings, like:
print "Jojo's .newsrc is ", -s "$~{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
"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 "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.
TO DO
· Become generally clearer on situations in which a user might not
have a particular resource.
· Merge remaining edge case code in File::HomeDir::Win32
· Add more granularity to Unix, and add support to VMS and other
esoteric platforms, so we can consider going core.
· Add consistent support for users_* methods
SUPPORT
This module is stored in an Open Repository at the following address.
<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 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.
<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.
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.
AUTHORS
Adam Kennedy <adamk@cpan.org>
Sean M. Burke <sburke@cpan.org>
Chris Nandor <cnandor@cpan.org>
Stephen Steneker <stennie@cpan.org>
SEE ALSO
File::ShareDir, File::HomeDir::Win32 (legacy)
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.
perl v5.10.0 2007-08-25 File::HomeDir(3)
