Output holds and windows

[Howard I. Cannon <HIC at MIT-MC>]

cc: AGRE at MIT-AI, BUG-LISPM at MIT-AI

Yes, it would be possible to see which window the process that the
wholine reflects is waiting for.  (It would require symevaling self
in that process' stack group, I believe).  RMS may know a kludge to do
it in the current window system.  On the other hand, this is a kludge.
The problem is that there may be an arbitrary number of processes in
output-hold, and output-hold is a legitimate state for a process to
be in!  Therefore, it is not clear what the right thing to do is.