The official info is in the Bash Manual, http://www.gnu.org/software/bash/manual/bashref.html#Programmable-Completion . A lot of distros come with a large collection of completion scripts, but where those are located depends a bit on the distro. For example, on my system it's /etc/bash_completion.d . If your system is different, check your ~/.bashrc, that usually calls some scripts in /etc, of which one will hopefully handle completion. Without digging into the completion script for Perl, it might be possible for you to just copy over the script from a "working" computer to one where it doesn't work - provided it's compatible with whatever version of bash is running there.