If I include the following in factorial_recurse.pl:

printf("perl5lib = $ENV{PERL5LIB}");
[download]

It prints:

perl5lib = /home/user/perl_modules/lib/perl5/x86_64-linux/
[download]

and nothing else. I don't see a path to either perl version referenced in my previous post (/tool/bin/perl

or

). Is that a problem?

The issue is that the libraries under that path are compiled for one of your perls, but not the other.

You need to have a separate directory for each perl version, each of which has a version of the libraries you are using. This is what Corion was recommending in 11136089.

A slightly more involved, but well tested and used, way to achieve this is to use local::lib to handle the different directories.

How do module directories get associated with specific installation locations of perl? When I install a module, I just do the following (as an example):

cd /home/user/perl_modules
cpanm -L$PWD Devel::NYTProf
[download]