- (djm) [regress/multiplex.sh] Skip test for non-OpenBSD netcat. We need
   a better solution, but this will have to do for now.
 - (djm) [regress/multiplex.sh] Instruct nc not to quit as soon as stdin
   is closed; avoid regress failures when stdin is /dev/null
 - (djm) [regress/multiplex.sh] Use -d (detach stdin) flag to disassociate
   nc from stdin, it's more portable