A little thought?

From: Robert Oliver (reply_at_newsgroup.only)
Date: 03/30/05 

Date: Tue, 29 Mar 2005 19:17:54 -0500
To:  dan.j@comcast.net

Dan,

Sorry to bug you about your old job, but we have a curious problem you
might have some insight into.

I've got a small SEL file. Display, FlightDatabase, Playback (File to
Message) running on some combination of 2 machines. All combinations
work, including all on either machine.

Add Autohandoff to the same machine as the display, and bad things
happen. Put it on the other machine and OK.

Remove Autohandoff and add ConflictAlert to the same machine as the
display, and bad things happen. Put it on the other machine and OK.

Run both Autohandoff and ConflictAlert and only one needs to be on the
other machine from the display.

When I say bad things happen, here's the deal:

We have a message queue to gate messages into the display. The first
message is sent directly to the display, subsequent messages are put in
   a queue. After sending, an event (sentinal) is sent to the display.
  When this comes back (via a callback) we send the next message in the
same way. The messages of concern are those that update aircraft
position. We seem to have a sentinal in the queue that is not processed
and therefore chokes the queue.

Targets are created but they fail to update for a long time. However,
if x events are generated, such as moving the mouse in the window, these
events allow the sentinals to propagate through the ODS event queue
(queue0) and everything works as it should. For example, if you wait 3
or 4 scans before generating x events, you will quickly get 3 or 4 scans
worth of updates. Either problem is odd in itself. The combination is
befuddling.

Any thoughts?

BTW: How is the legacy code comming? Did you get the book yet?

Thanks,

Bob

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