A somewhat simpler approach for a "semi-permanent" solution may be to set the PERL5LIB environment variable to the directories you want to always make available. See perlrun.

set the PERL5LIB environment variable

In my experience, ensuring that an environment variable is set for every possible process that might execute my script is pretty unlikely, not to mention that a setuid script ignores that variable.

-- Randal L. Schwartz, Perl hacker
Be sure to read my standard disclaimer if this is a reply.

I like to give people options. Not everyone feels comfortable recompiling perl. Given that the OP was looking in Super Search to find out about use lib, it seemed to me that a recompile or editing the binary might be the proverbial atomic bomb to swat a fly.

-xdg

Code written by xdg and posted on PerlMonks is public domain. It is provided as is with no warranties, express or implied, of any kind. Posted code may not have been tested. Use of posted code is at your own risk.

He could begin his script with

#!/usr/bin/perl -mlib=/path
[download]