CAMThread.CallWorker method
[The feature associated with this page, DirectShow, is a legacy feature. It has been superseded by MediaPlayer, IMFMediaEngine, and Audio/Video Capture in Media Foundation. Those features have been optimized for Windows 10 and Windows 11. Microsoft strongly recommends that new code use MediaPlayer, IMFMediaEngine and Audio/Video Capture in Media Foundation instead of DirectShow, when possible. Microsoft suggests that existing code that uses the legacy APIs be rewritten to use the new APIs if possible.]
The CallWorker method signals the thread with a request.
Syntax
DWORD CallWorker(
DWORD dwParam
);
Parameters
-
dwParam
-
Request parameter. The derived class defines the meaning of the parameter.
Return value
Returns a value that is defined by the derived class.
Remarks
The CAMThread::GetRequest and CAMThread::CheckRequest methods retrieve the value of the dwParam parameter. The GetRequest method blocks until CallWorker is called.
This method blocks until the CAMThread::Reply method is called. The return value is the parameter given to Reply.
This method holds the CAMThread::m_AccessLock lock to serialize requests. Therefore, do call this method from the thread itself or from any member function that executes in the context of the thread.
Requirements
| Requirement | Value |
|---|---|
| Header |
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| Library |
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