If the return value is zero, the specified thread was not suspended. If the return value is 1, the specified thread was suspended but was restarted. If the return value is greater than 1, the specified thread is still suspended.
BOOL GetExitCodeThread(
HANDLE hThread, // handle to the thread
LPDWORD lpExitCode // address to receive termination status
);
//
If the specified thread has not terminated, the termination status returned is STILL_ACTIVE.