


lib(3p)          Perl Programmers Reference Guide         lib(3p)


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.



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lib(3p)          Perl Programmers Reference Guide         lib(3p)


       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.




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lib(3p)          Perl Programmers Reference Guide         lib(3p)


       "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 <perl5-porters@perl.org>

       Maintainer of the CPAN release: Steffen Mueller
       <smueller@cpan.org>

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.








































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