Code review comment for lp:~justin-fathomdb/nova/check-subprocess-exit-code

Sure - the primary case I was trying to fix when messing with the Twisted code (which is what I think you're questioning), is the one in this comment:

# NOTE(termie): current behavior means if error_ok is True
# we won't throw an error even if the process
# exited with a non-0 status, so you can't be
# okay with stderr output and not with bad exit
# codes.

I cleaned up the logic so that we can still check the exit code, whether or not the process outputs on stderr.