A Handy Thread Synchronization Object Chart

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The following chart summarizes how the various kernel objects behave with respect to thread synchronization.

Object	When Nonsignaled	When Signaled	Successful Wait Side Effect
Process	While process is still active	When process terminates (ExitProcess, TerminateProcess)	None
Thread	While thread is still active	When thread terminates (ExitThread, TerminateThread)	None
Job	When job's time has not expired	When job time expires	None
File	When I/O request is pending	When I/O request completes	None
Console input	No input exists	When input is available	None
File change notifications	No files have changed	When file system detects changes	Resets notification
Auto-reset event	ResetEvent, PulseEvent, or successful wait	When SetEvent/PulseEvent is called	Resets event
Manual-reset event	ResetEvent or PulseEvent	When SetEvent/PulseEvent is called	None
Auto-reset waitable timer	CancelWaitableTimer or successful wait	When time comes due (SetWaitableTimer)	Resets timer
Manual-reset waitable timer	CancelWaitableTimer	When time comes due (SetWaitableTimer)	None
Semaphore	Successful wait	When count > 0 (ReleaseSemaphore)	Decrements count by 1
Mutex	Successful wait	When unowned by a thread (ReleaseMutex)	Gives ownership to thread
Critical section (user-mode)	Successful wait ((Try)EnterCriticalSection)	When unowned by a thread (LeaveCriticalSection)	Gives ownership to thread

Interlocked (user-mode) functions never cause a thread to be unschedulable; they alter a value and return immediately.