🚀 go-pugleaf

>>If that's not the case, i.e. as long as the processing time less than the
>>interval I can rely on the timer(?)
> Depends on how you are invoking the timer. If you are using a WM_TIMER
> message (SetTimer), then it is just pulled out of your windows application
> message queue like any other message. It won't be processed until your
> message loop runs. If your program is busy doing something else when

It's even worst than that - not only will the WM_TIMER message not be
dealt with until the message queue is processed, it won't be processed
until the message queue is *empty*. It is really just a flag that the
message queue processor in Windows checks for when there are no more
messages on an application's queue. If it is set, the processor sends
your app the WM_TIMER message.

> If you are worried about accuracy (and it sounds like you are), you need to
> use the multi-media timer functions (see timeSetEvent) and use a callback

You can also use a component to do this. Just drop it on your format, and
set the event handler. There are a few out there, but I recommend the
shareware ZieglerCollection, which includes this, buttons, app events, and
a whole bunch more:

http://www.zieglersoft.com

-- 
Jonathan Arnold         C/C++/CBuilder Keen Advice:
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    Comprehensive C++Builder link site:
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