On windows 7, thread appears to be hung at _endthreadex and Waitforsingleobject with a timeout doesn't signal

[Anju Maria]

hi All,


I need your help with a random hang issue we are facing with our desktop application.


We have a thread implemented to call Beep and Sleep APIs in a loop. So we start the thread to call these and then after some time, we break the loop, waitforsingleobject with a timeout in the main thread and come out of the thread. Just before returning from the thread function, we call _endthreadex. There is a hang here. Now I dont know whether the _endthreadex is failing and how it is stopping the waitforsingleobject from signalling after the timeout. The code is implemented pretty much similar to what is documented as an example for _beginthreadex. As I said, it occurs very randomly and on few machines.


unsigned __stdcall SecondThreadFunc( void* pArguments )

{

printf( "In second thread...\n" );

while( m_iBeepMode == iBEEPON )

{

Beep(600, 100);

Sleep(100);

}

//I added a logging here, which gets logged in hang case.

_endthreadex( 0 );

return 0;

}

int main()

{

HANDLE hThread;

unsigned threadID;

printf( "Creating second thread...\n" );

// Create the second thread.

hThread = (HANDLE)_beginthreadex( NULL, 16384, &SecondThreadFunc, this, 0, &threadID );


// the below code is not exactly in the same method. We call it at a later time to stop the beep.

m_iBeepMode = BEEPOFF;

WaitForSingleObject( hThread, 10000 );

// Added a logging here, which doesn't get logged.

// Destroy the thread object.

CloseHandle( hThread );

}

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