Manfred Spraul <manfred@colorfullife.com> writes:
>> return false; /* No threading, so we can't be in send() */
> Why not? Signal delivery can interrupt send() even with single-threaded
> users.
It looks like Bruce left the old logic in place for unthreaded
implementations: we just replace the signal handler during every send().
So there's no need for PQinSend() to do anything useful.
regards, tom lane