what actually happens when sending a message out of a repeat loop?

[Richard Gaskin]

Sivakatirswami wrote:

> Aloha, Richard:
> 
> I got to see your picture from Andre's camera as you roamed the dry zone 
> in Nevada. We had a center in Virginia City for years.  I loved the 
> silence of the desert!

After living in Los Angeles for so long, I consider it invaluable. :)

> Anyway, I can now put a face to your name. The man who told me about 
> metacard years ago and i never looked back...(smile) 

It's been a good journey, eh?

But if I'm not mistaken, didn't we first meet at a SuperCard conference 
in '96?  Or was that another gentleman from your ashram?

> I have an interest in the above "send" issues... 
> 
> You say "...then the repeat loop will continue, and DoSomething (like 
> all timer messages) will only be fired once the engine hits idle."
> 
> But, are they not piling up in the MessageQueue, to be executed, one 
> after another, never the less? And if params are sent along with the 
> cmd, are they also queued up?

That's my understanding:  all pending messages are queued until idle, 
which can raise concerns about the sort of race conditions the original 
poster mentioned.

One of the best ways I've found to reduce CPU usage is to turn down the 
frequency of any polling timers (timers that call themselves); for the 
user there's often not much difference between 1/100th of a second and 
1/20th, but it can take a huge load off the CPU to turn it down.

Also, in polling timers I've found it very helpful to first check to see 
if a message is already queued before queueing it again, e.g.:

  on DoPolling
    DoSomething
    if "DoPolling" is not in the pendingMessages then
      send "DoPolling" to me in 200 millisecs
    end if
  end DoPolling

Without that check, if the time between idle exceeds the time to your 
next pending message you can queue up redundant calls.

-- 
  Richard Gaskin
  Fourth World Media Corporation
  ___________________________________________________________
  Ambassador at FourthWorld.com       http://www.FourthWorld.com