Strange Hangs on VNC for Win-95

James [Wez] Weatherall jnw "at"
Sat, 07 Mar 1998 16:17:15 +0000

On Fri, 6 Mar 1998, John C. Hayward wrote:

[snip - problems using Access-2.0 on Win95 with WinVNC]
> Anyone else see this kind of behavior?  Is it because Access-2.0 is a 16
> bit application?  It seems that the problem is that the server misses some
> mouse movement from the client because of the heavy activity of the
> 16 bit application and that moving the mouse on the server triggers some
> activity that the server can now respond to the pending requests from the
> client.

It's quite likely that this (a priority problem) is the cause of the
behaviour.  WinVNC also places some "registered" window messages into the
message queues of hooked applications in order to time updates properly,
so this may be confusing the program.  I'd be interested to know how the
same situation behaves on NT, since the scheduling system on NT differs
radically from '95 - '95 reverts to cooperative scheduling while running
16-bit applications, so WinVNC won't get scheduled AT ALL if such an
application goes into a tight loop.

Cheers for the feedback.  I'll look into it.

James "Wez" Weatherall
Olivetti & Oracle Research Laboratory, Cambridge, UK.
Tel : Work - 343000