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CDynamicOutputPin::AsynchronousBlockOutputPin

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Microsoft DirectShow 9.0

CDynamicOutputPin::AsynchronousBlockOutputPin

The AsynchronousBlockOutputPin method blocks the pin. The method might return before the pin is blocked.

Syntax

  HRESULT AsynchronousBlockOutputPin(
    HANDLE hNotifyCallerPinBlockedEvent
);

Parameters

hNotifyCallerPinBlockedEvent

Handle to an event. The event is signaled when the output pin is blocked, or if the caller cancels the block operation.

Return Value

Returns an HRESULT value. Possible values include those shown in the following table.

Value Description
S_OK Success.
VFW_E_PIN_ALREADY_BLOCKED Pin is already blocked on another thread.
VFW_E_PIN_ALREADY_BLOCKED_ON_THIS_THREAD Pin is already blocked on the calling thread.

Remarks

Do not call this method from the streaming thread.

If no streaming thread is using the pin, this method immediately blocks the pin. Otherwise, it sets the pin status to "pending" and returns. When the streaming operation completes, the streaming thread calls the CDynamicOutputPin::StopUsingOutputPin method, which blocks the pin and signals the hNotifyCallerPinBlockedEvent event. To cancel a pending block, call the CDynamicOutputPin::UnblockOutputPin method.

Requirements

**  Header:** Declared in Amfilter.h; include Streams.h.

**  Library:** Use Strmbase.lib (retail builds) or Strmbasd.lib (debug builds).

See Also