if ref $CHILDREN{$child} eq 'CODE';

I believe this checks to see if the reference type of $CHILDREN{$child} is CODE -- that is, is it a coderef.

kill TERM => keys %CHILDREN;

Again, from the reference section of v3 of the Camel, kill takes a SIGNAL and a LIST. The => is a substitue for a comma.

ps I'm not crazy about the use of ALL CAPS variable names, but am I gonna argue with Lincoln Stein?

--t. alex

"Mud, mud, glorious mud. Nothing quite like it for cooling the blood!"
--Michael Flanders and Donald Swann