CAMMsgEvent::WaitMsg

 
Microsoft DirectShow 9.0

CAMMsgEvent::WaitMsg

The WaitMsg method waits for the event to be signaled, while dispatching sent messages.

Syntax

  BOOL WaitMsg(
    DWORD dwTimeOut = INFINITE
);

Parameters

dwTimeOut

Optional time-out value, in milliseconds.

Return Value

Returns TRUE if the event is signaled, or FALSE if the time-out occurred.

Remarks

This method calls the PeekMessage function to process messages. Call this method instead of CAMEvent::Wait if your thread needs to process messages while waiting for an event. If the thread does not process messages and another thread sends a message, deadlock could occur.

For example, suppose you create a thread and then block until the thread initializes. If the thread sends a message to your window by calling the SendMessage function, it will result in a deadlock. This is because SendMessage does not return until the message has been processed. Calling WaitMsg allows the SendMessage call to return, preventing the deadlock.

Requirements

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

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

See Also