ReleaseSemaphore does not release the semaphore

Question

(In short: main()\'s WaitForSingleObject hangs in the program below).

I\'m trying to write a piece of code that dispatches threads and waits for them to finish befor

Answer 1

I don't understand the code, but the threading sync is definitely bad. You assume that threads will call SuspendThread() in a certain order. A succeeded WaitForSingleObject() call doesn't tell you which thread called ReleaseSemaphore(). You'll thus call ReleaseThread() on a thread that wasn't suspended. This quickly deadlocks the program.

Another bad assumption is that a thread already called SuspendThread after the WFSO returned. Usually yes, not always. The thread could be pre-empted right after the RS call. You'll again call ReleaseThread() on a thread that wasn't suspended. That one usually takes a day or so to deadlock your program.

And I think there's one ReleaseSemaphore call too many. Trying to unwedge it, no doubt.

You cannot control threading with Suspend/ReleaseThread(), don't try.