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

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. lib.pm
       also checks if directories called $dir/$version and
       $dir/$version/$archname exist and deletes these directories 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 <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.

perl v5.32.0			  2020-08-08				lib(3)

NAME | SYNOPSIS | DESCRIPTION | CAVEATS | NOTES | SEE ALSO | AUTHOR | COPYRIGHT AND LICENSE

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