You are correct that the wait should be in a loop such as the reap_children function has. I was clearly not thinking clearly... Also, on SYS V systems IIRC CHLD or CLD signals are regenerated if you do not do wait on the clild so the race condidion you mention may not hold true there and wait by itself should work. I suppose I've been using SYS V-based systems too much to think of some of these issues. My bad.

tye is correct. To be portable you'll need to find another solution. I have used non-blocking waits in a timer loop to clean up children and that may work here. Of course, if you don't care about portability, use what works on your system and document that it isn't portable.