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IPinConnection::NotifyEndOfStream

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Microsoft DirectShow 9.0

IPinConnection::NotifyEndOfStream

The NotifyEndOfStream method requests notification from the pin when the next end-of-stream condition occurs.

Syntax

  HRESULT NotifyEndOfStream(
  HANDLE hNotifyEvent
);

Parameters

hNotifyEvent

[in] Handle to an event object that the pin will signal.

Return Value

Returns an HRESULT value. Possible values include the following.

Value Description
S_FALSE Event handle was NULL, but there was no existing event handle to reset.
S_OK Event handle was set. (If event handle was NULL, event notification was canceled.)

Remarks

This method enables the caller to push data through a portion of the filter graph ending with this pin.

For example, suppose the caller is pushing data from an output pin called "A" on one filter, to an input pin called "B" on another filter, possibly with intermediate filters connecting them. The following sequence of events would take place.

  1. The caller blocks the data flow at pin A.
  2. It calls NotifyEndOfStream on pin B.
  3. It calls IPin::EndOfStream on the input pin connected to pin A.
  4. As the remaining data travels downstream through any intermediate filters, those filters propagate the end-of-stream notification.
  5. When pin B receives the end-of-stream notification, it signals the event given in the hNotifyEvent parameter. At that point, the caller can safely reconfigure the graph between pin A and pin B.

Because the purpose of this method is to enable the caller to rebuild the graph dynamically and then restart the connection, the end-of-stream notification does not represent the actual end of the stream. Therefore, pin B does not propagate the end-of-stream condition or signal EC_COMPLETE. This is an exception to the usual rules for data flow in the filter graph.

It is the caller's responsibility to cancel notification by calling this method again with a NULL event handle.

The filter graph calls this method inside the IGraphConfig::Reconnect method. If an application or filter does any specialized dynamic reconfiguration to the graph (using the IGraphConfig::Reconfigure method), it might call this method first in order to push data through the portion of the graph that is being reconfigured.

Requirements

Header: Declared in Strmif.h; include Dshow.h.

Library: Use Strmiids.lib.

See Also