I came up with a need to use regular expressions. In my case my goal was to get the just the filename from a full path. Here is my hack; ------------ #!/usr/bin/perl $_ = $ARGV[0]; $_ =~ s|^.*/([^/]*)$|$1|; print $_; ------------ Simply invoke the script via PD using ... | [/home/me/pd/filename.pl $1( | [shell] | [pack s] | ... andy