r9619: Fix messages_pending_for_pid actually do what it's meant to do. This might be

r9619: Fix messages_pending_for_pid actually do what it's meant to do. This might be
a big relief on messages.tdb contention as ignoring processes with >1000
messages in printing/notify.c should work correctly now.

Jeremy, Jerry told me to ask you about printer scalability torture tests, this
might be a reason why you implemented the message_send_pid_with_timeout
using the signal (shudder) in the first place. :-)

While looking at that... Wouldn't it be better to not use the signal but have
an overall timeout for print_notify_send_messages using GetTimeOfDay & friends
and not use the alarm signal deep inside tdb.c?

Volker
(This used to be commit b5e82bb512d3425839e061e78f4d6fe0bd05b708)