The Old New Thing

Dispelling the myths, rumors, and innuendo surrounding the QueryPerformanceCounter function

August 22, 2014 Aug 22, 2014 08/22/14

Raymond Chen

The function has been the subject of much rumor and innuendo. In response to all the confusion, the kernel folks put together a page which tries to settle the controversy once and for all. It discusses the history of QPC over the ages, the problems it had on earlier versions of Windows or older firmware (which is probably where a lot of the...

Why does the OpenThread function behave differently when the target thread belongs to another process?

August 22, 2014 Aug 22, 2014 08/22/14

Raymond Chen

A customer discovered strange behavior in the function and wondered whether it was expected. We use the function to obtain a thread handle with , passing in a valid thread ID. We later pass this handle to to get the thread exit code. We have found that the function succeeds if the thread in question belongs to another process, provided the...