Thread: _beginthread()

When I use _beginthread(), it doesn't run the thread everytime. Is there a way to be sure the call to another thread will run?

Thanks,
Matt

Code:

...
else if((!bRewarded) && (bICTA) && (bInRef)) {
ldHotClk = ldStateCtr - ldHotRef;
if(ldHotClk > iTime)	{						
bRewarded = true;
++iRewardNum;
bICTA = false;
ldColdClk = 0;
ldHoldColdClk = 0;
ldHoldEndColdClk = 0;
bOutRef = false;				
_beginthread(SignalPlacePref, 0, NULL);
}
...

/*****************************************************/
void SignalPlacePref(void)
{
	bThreadFunctCalled = true;
	if(!bRewardiscontinue)	{
		cbDBitOut(iBoardNum, iPortType, iBitNum1, 1);	//	Raise digital bit 1 to set Enable Hi
		Sleep(5);										//	Wait to besure Enable is Hi before next step
		cbDBitOut(iBoardNum, iPortType, iBitNum0, 1);	//	Raise digital bit 0 to trigger plt fdr
		Sleep(10);										//	Ensure long pulse for triggering plt fdr
		cbDBitOut(iBoardNum, iPortType, iBitNum0, 0);	//	Bring bits down
		cbDBitOut(iBoardNum, iPortType, iBitNum1, 0);
	}
	_endthread();
}
/*******************************************************/

How have you determined that it does not run the thread everytime? A test case would be appreciated:

http://jcatki.no-ip.org/fncpp/TestCase

Also, what are you doing that requires threads. The major problem with threads is peopel seem to use them in places that they deffinatly shouldn't. Are you sure you ened threads here? They mostly complicate programs instead of make them simpler.

Thanks for the reply. In the code for the thread, I set bThreadFunctCalled = true. If the thread was not called, then bThreadFunctCalled = false. I look in an output file that writes out variables so I can see when bThreadFunctCalled = true. This coordinates with some of the other variables, but it doesn't work right (i.e. I no longer see bThreadFunctCalled = true)
The code in the thread sets a bit HI on a PCI digital IO board which will trigger a pellet feeder. The feeder beeps when it is triggered. This isn't working because there is no pellet or beep.
I need to do this because this is a real-time video tracking program and I need to process each frame within a small window of time or I'll drop a frame.

If you need to process each frame within a window then threads are probably going to give you worse performance. The context switch between threads takes time. Especially if you are spawning a lot you are going to be spending more time goign between threads than actually processing. You can probably do this much simpler by breaking your algorithm into logical, short, chunks and swiching between them in a single thread. You avoid the threading here, thus context switches. You also don't have to worry about any issues that come with threads such as synchronization and deadlocks. Debugging will also most likely be much simpler. The hardest part is probably going to be deciding how much time to give each chunk at a time.