Perl – How to automate CPAN configuration

This is answered in the Perl FAQ, the answer which can be quickly found with perldoc -q installed. In short, it comes down to using ExtUtils::Installed or using File::Find, variants of both of which have been covered previously in this thread.

You can also find the FAQ entry "How do I find which modules are installed on my system?" in perlfaq3. You can see a list of all FAQ answers by looking in perlfaq

If you want to install the Perl distribution in the current directory, use the dot instead of a filename:

 cpan .

If you are using one of the latest versions of the cpan program (not the one that currently comes with CPAN.pm), you can use the -j switch to specify an alternate configuration file where you can set the --install_base or INSTALL_BASE directives, and also set values for options like connect_to_internet_ok.

 cpan -j /path/to/Config.pm Foo::Bar

If you want to modify your current config to make your alternate config file, use -J to get the file text:

 cpan -J

Ideally, instead for giving you superuser priveleges, that sysadmin would have created a group for Perl admins, would have specified a directory for module installations owned by that group, and added you to that group. You wouldn't need any special powers then.