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NAME
    lib - manipulate @INC at compile time

SYNOPSIS
        use lib LIST;

        no lib LIST;

DESCRIPTION
    This is a small simple module which simplifies the manipulation of @INC
    at compile time.

    It is typically used to add extra directories to perl's search path so
    that later "use" or "require" statements will find modules which are not
    located on perl's default search path.

  Adding directories to @INC
    The parameters to "use lib" are added to the start of the perl search
    path. Saying

        use lib LIST;

    is *almost* the same as saying

        BEGIN { unshift(@INC, LIST) }

    For each directory in LIST (called $dir here) the lib module also checks
    to see if a directory called $dir/$archname/auto exists. If so the
    $dir/$archname directory is assumed to be a corresponding architecture
    specific directory and is added to @INC in front of $dir. lib.pm also
    checks if directories called $dir/$version and $dir/$version/$archname
    exist and adds these directories to @INC.

    The current value of $archname can be found with this command:

        perl -V:archname

    The corresponding command to get the current value of $version is:

        perl -V:version

    To avoid memory leaks, all trailing duplicate entries in @INC are
    removed.

  Deleting directories from @INC
    You should normally only add directories to @INC. If you need to delete
    directories from @INC take care to only delete those which you added
    yourself or which you are certain are not needed by other modules in
    your script. Other modules may have added directories which they need
    for correct operation.

    The "no lib" statement deletes all instances of each named directory
    from @INC.

    For each directory in LIST (called $dir here) the lib module also checks
    to see if a directory called $dir/$archname/auto exists. If so the
    $dir/$archname directory is assumed to be a corresponding architecture
    specific directory and is also deleted from @INC.

  Restoring original @INC
    When the lib module is first loaded it records the current value of @INC
    in an array @lib::ORIG_INC. To restore @INC to that value you can say

        @INC = @lib::ORIG_INC;

CAVEATS
    In order to keep lib.pm small and simple, it only works with Unix
    filepaths. This doesn't mean it only works on Unix, but non-Unix users
    must first translate their file paths to Unix conventions.

        # VMS users wanting to put [.stuff.moo] into 
        # their @INC would write
        use lib 'stuff/moo';

NOTES
    In the future, this module will likely use File::Spec for determining
    paths, as it does now for Mac OS (where Unix-style or Mac-style paths
    work, and Unix-style paths are converted properly to Mac-style paths
    before being added to @INC).

    If you try to add a file to @INC as follows:

      use lib 'this_is_a_file.txt';

    "lib" will warn about this. The sole exceptions are files with the
    ".par" extension which are intended to be used as libraries.

SEE ALSO
    FindBin - optional module which deals with paths relative to the source
    file.

    PAR - optional module which can treat ".par" files as Perl libraries.

AUTHOR
    Tim Bunce, 2nd June 1995.

    "lib" is maintained by the perl5-porters. Please direct any questions to
    the canonical mailing list. Anything that is applicable to the CPAN
    release can be sent to its maintainer, though.

    Maintainer: The Perl5-Porters <[email protected]>

    Maintainer of the CPAN release: Steffen Mueller <[email protected]>

COPYRIGHT AND LICENSE
    This package has been part of the perl core since perl 5.001. It has
    been released separately to CPAN so older installations can benefit from
    bug fixes.

    This package has the same copyright and license as the perl core.