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CMsgThread::ThreadMessageProc

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Microsoft DirectShow 9.0

CMsgThread::ThreadMessageProc

Processes requests. This is a pure virtual member function.

Syntax

  virtual LRESULT ThreadMessageProc(
    UINT uMsg,
    DWORD dwFlags,
    LPVOID lpParam,
    CAMEvent *pEvent
);

Parameters

uMsg

Request code.

dwFlags

Optional flag parameter to request.

lpParam

Optional pointer to extra data or a return data block.

pEvent

Optional pointer to an event object.

Return Value

Any nonzero return causes the thread to exit. Returns zero unless an exit request has been processed recently.

Remarks

This pure virtual function must be overridden in your derived class. It will be called once for each request queued by a call to the CMsgThread::PutThreadMsg member function.

The member function defines the four parameters. Typically, use the uMsg parameter to indicate the request, and the other three parameters will be optional additional parameters. The calling application can supply a pointer to a CAMEvent object in the pEvent parameter if your application requires it. You must set this event after processing the event by using an expression such as:

pEvent->SetEvent

One request code must be set aside to tell the worker thread to exit. Upon receiving this request, return 1 from this member function. Return 0 if you do not want the worker thread to exit.

Requirements

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

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

See Also