1lib(3pm)               Perl Programmers Reference Guide               lib(3pm)
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NAME

6       lib - manipulate @INC at compile time
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SYNOPSIS

9           use lib LIST;
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11           no lib LIST;
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DESCRIPTION

14       This is a small simple module which simplifies the manipulation of @INC
15       at compile time.
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17       It is typically used to add extra directories to perl's search path so
18       that later "use" or "require" statements will find modules which are
19       not located on perl's default search path.
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21       Adding directories to @INC
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23       The parameters to "use lib" are added to the start of the perl search
24       path. Saying
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26           use lib LIST;
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28       is almost the same as saying
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30           BEGIN { unshift(@INC, LIST) }
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32       For each directory in LIST (called $dir here) the lib module also
33       checks to see if a directory called $dir/$archname/auto exists.  If so
34       the $dir/$archname directory is assumed to be a corresponding architec‐
35       ture specific directory and is added to @INC in front of $dir.
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37       To avoid memory leaks, all trailing duplicate entries in @INC are
38       removed.
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40       Deleting directories from @INC
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42       You should normally only add directories to @INC.  If you need to
43       delete directories from @INC take care to only delete those which you
44       added yourself or which you are certain are not needed by other modules
45       in your script.  Other modules may have added directories which they
46       need for correct operation.
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48       The "no lib" statement deletes all instances of each named directory
49       from @INC.
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51       For each directory in LIST (called $dir here) the lib module also
52       checks to see if a directory called $dir/$archname/auto exists.  If so
53       the $dir/$archname directory is assumed to be a corresponding architec‐
54       ture specific directory and is also deleted from @INC.
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56       Restoring original @INC
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58       When the lib module is first loaded it records the current value of
59       @INC in an array @lib::ORIG_INC. To restore @INC to that value you can
60       say
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62           @INC = @lib::ORIG_INC;
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CAVEATS

65       In order to keep lib.pm small and simple, it only works with Unix
66       filepaths.  This doesn't mean it only works on Unix, but non-Unix users
67       must first translate their file paths to Unix conventions.
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69           # VMS users wanting to put [.stuff.moo] into
70           # their @INC would write
71           use lib 'stuff/moo';
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NOTES

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

80       FindBin - optional module which deals with paths relative to the source
81       file.
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AUTHOR

84       Tim Bunce, 2nd June 1995.
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88perl v5.8.8                       2001-09-21                          lib(3pm)
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