I wonder how setevent is handled internally within Windows.

I have the following situation

Std::thread thread loop which executes while std::atomic == true Inside the loop is a waitforsingleObject which sleeps infinite in alertable state.

A function stopThread() which does the following: - Clears the atomic bool - Calls Setevent on the event object - Calls thread.join

This often hangs, I get the impression that setevent has still some work to do in the current thread, while join blocks the current thread.

If I add an additional Boolean in the thread which is set after waitforsinlgleObject and I wait for this to be set before calling join() Everything seems to work ok.

Code (error checking omitted here)

Init code/declarations:

 HANDLE m_WakeupThreadEvent;
 std::atomic<bool> m_ReceiverEnabled;
 m_WakeupThreadEvent = CreateEvent(NULL, false, false, "RxThreadWakeupEvent" );

Thread code:

while(m_ReceiverEnabled)
{
    DWORD rslt = WaitForSingleObjectEx(m_WakeupThreadEvent, INFINITE, true);
    // Here some checking for rslt;
}

function code:

m_ReceiverEnabled = true;
SetEvent( m_WakeupThreadEvent )
m_Thread.join()

Is there some explanation for this behavior ? I could not find any details about the operation of setEvent()