PulseEvent info  Overview  Group

The PulseEvent function provides a single operation that sets (to signaled) the state of the specified event object and then resets it (to nonsignaled) after releasing the appropriate number of waiting threads.

BOOL PulseEvent(

Parameters

hEvent

Identifies the event object. The CreateEvent or OpenEvent function returns this handle.

Windows NT: The handle must have EVENT_MODIFY_STATE access. For more information, see Interprocess Synchronization Objects.

Return Values

If the function succeeds, the return value is nonzero.

If the function fails, the return value is zero. To get extended error information, call GetLastError.

Remarks

For a manual-reset event object, all waiting threads that can be released immediately are released. The function then resets the event object’s state to nonsignaled and returns.

For an auto-reset event object, the function resets the state to nonsignaled and returns after releasing a single waiting thread, even if multiple threads are waiting.

If no threads are waiting, or if no thread can be released immediately, PulseEvent simply sets the event object’s state to nonsignaled and returns.

Note that for a thread using the multiple-object wait functions to wait for all specified objects to be signaled, PulseEvent can set the event object’s state to signaled and reset it to nonsignaled without causing the wait function to return. This happens if not all of the specified objects are simultaneously signaled.

See Also

CreateEvent, OpenEvent, ResetEvent, SetEvent