Problem solved. ID-10-T error.
Lesson #1: strace is your friend.
Lesson #2: Man pages are your friends. I wasn't aware that strace could
attach to currently
running processes.
Lesson #3: Never never never never never never never assume your variables
have been
pre-initialized. I was neglecting to make sure that the list of sockets
that select() listens
to was empty before I started adding to it.
The problem wasn't with svscan/supervise at all, but you all probably knew
that already.
Thanks for the insight, Charles, it helped. I'm going to go bang my head
on the wall for a bit, now.
---Kris Kelley