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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.

       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).

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

AUTHOR
       Tim Bunce, 2nd June 1995.



perl v5.8.8                       2001-09-21                            lib(3)