PGP file encryption

I've need to automate file encryption using PGP. Has anyone had any experiences with this that they can share? I'm having difficulty searching for this because of so many PGP signatures on posts. Thanks much.

I implemented PGP signing of outgoing mail in Perl, using the gpg binary directly. Sure, it won't work on windows, but I controlled the horizontal and vertical, and could mandate Unix-like OS.

--Michael