title: Who is the calling thread of the callback function set by CreateTimerQueueTimer()?
body: <p>I guess it's the thread, say A, on which the timer was created. But I can't figure out how exactly the callback function is called. Assume the timer expires, and then what happens? Does this happen when this thread gets its time slice? And if this is the case, I think the function should be called by the scheduler or what before the context is finally switched to A, then can I say A is the caller? </p>
  
  <p>Thanks.</p>