FindBin is a standard module that solves this problem. (sort of)

use FindBin qw($Bin);
use lib "$Bin/../lib";
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L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

Find::Lib appears to be exactly that.

use Find::Lib '../lib';
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By the way, you have abs_path (aka realpath) and dirname backwards.

use Cwd            qw( abs_path );
use File::Basename qw( dirname );

use lib dirname(abs_path($0)).'/../lib';
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The order in which you use them will fail if you create a symlink to the script.

Update: Find::Lib touts its handling of symlinks, but it fails to handle a symlink to the script.

$ find ! -type d -exec ls -l {} +
lrwxrwxrwx 1 eric users  8 Feb 22 17:04 ./a.pl -> bin/a.pl
-rwx------ 1 eric users 53 Feb 22 17:04 ./bin/a.pl
-rw------- 1 eric users 16 Feb 22 17:03 ./lib/Mod.pm

$ cat bin/a.pl
#!/usr/bin/env perl
use Find::Lib '../lib';
use Mod;

$ cat lib/Mod.pm
package Mod;
1;

$ bin/a.pl

$ a.pl
Can't locate Mod.pm in @INC (@INC contains: /home/eric/usr/perlbrew/pe
+rls/perl-5.12.2/lib/site_perl/5.12.2/i686-linux /home/eric/usr/perlbr
+ew/perls/perl-5.12.2/lib/site_perl/5.12.2 /home/eric/usr/perlbrew/per
+ls/perl-5.12.2/lib/5.12.2/i686-linux /home/eric/usr/perlbrew/perls/pe
+rl-5.12.2/lib/5.12.2 .) at ./a.pl line 3.
BEGIN failed--compilation aborted at ./a.pl line 3.
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I do the same thing in certain scripts, so would be curious if someone suggested another solution.

Also, I use __FILE__ instead, to ensure that it's relative to the current file instead of the executing script.

# use lib <Relative Directory>
use lib;
use Cwd qw(abs_path);
use File::Basename qw(dirname);
BEGIN {
    my $dirname = dirname(__FILE__);
    my $perl = abs_path("$dirname/../../perl");

    lib->import($perl);
}
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It seems very odd to me that you would want to add to @INC in anything but the executing script.

ikegami:

I think he meant it as a way to avoid something like:

$ mkdir -p TEST/{bin,sl}/lib

$ echo -e "package myLib;\nour \$VERSION=1.1;\n" >TEST/sl/lib/myLib.pm

$ echo -e "package myLib;\nour \$VERSION=1.7;\n" >TEST/bin/lib/myLib.p
+m

$ cp printval.pl TEST/bin

$ cd TEST/bin

$ ./printval.pl 
myLib version: 1.7
search path: /home/marco/TEST/bin/lib
/etc/perl
/usr/local/lib/perl/5.10.1
    . . .

$ cd ../sl

$ ln --symbolic ../bin/printval.pl printval

$ ./printval 
myLib version: 1.1
search path: /home/marco/TEST/sl/lib
/etc/perl
/usr/local/lib/perl/5.10.1
    . . .

$ cat ../bin/printval.pl 
#!/usr/bin/perl
use strict;
use warnings;
use File::Basename;
use Cwd 'abs_path';
my $f;
BEGIN {
    unshift(@INC, abs_path(dirname($0).'/lib'));
}
use myLib;
print "myLib version: ", $myLib::VERSION, "\n";
print "search path: ", join("\n", @INC[0 .. 2], "\t. . ."), "\n";
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...roboticus

When your only tool is a hammer, all problems look like your thumb.

I use lib with that sort of thing all the time by going through a variable...

my $rundir;
BEGIN { use File::Basename; $rundir = dirname($0); }
use lib "$rundir/lib";
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