in reply to "Single-machine IPC via sockets" and other things to say in the dark

Again, I can't overemphasize the advantage of using a well-known-protocol for the communication. In this case, my favorite round-trip of choice is HTTP. Look into creating a server with HTTP::Daemon, and then your client can perform transactactions with easily-generated LWP::UserAgent objects.

-- Randal L. Schwartz, Perl hacker