CAMMsgEvent Class

CAMMsgEvent class hierarchy

The CAMMsgEvent class is a wrapper for event objects that do message processing. This class adds one method to the CAMEvent object to enable sent messages to be processed while waiting.

Member Functions

WaitMsg Enables sent messages to be processed while waiting for an event to be signaled or for the indicated time-out to occur.

CAMMsgEvent::WaitMsg

CAMMsgEvent Class

Enables sent messages to be processed while waiting for an event to be signaled or for the indicated time-out to occur.

Syntax

BOOL WaitMsg(
    DWORD dwTimeOut = INFINITE
    );

Parameters

dwTimeOut
Optional time-out value, represented in milliseconds.

Return Value

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

Remarks

Call CAMMsgEvent::WaitMsg rather than CAMEvent::Wait if you want to block on a time-out or a signaled event and continue to process sent messages. If you do not process messages and another thread sends you a message, deadlock could occur. For example, if you create a thread by way of the Win32 CreateThread function and then block until the thread can initialize, deadlock will occur if the thread sends a message to your window using the Win32 SendMessage function. This is because SendMessage does not return until the message has been processed. CAMMsgEvent::WaitMsg allows SendMessage to return to the caller by using a Win32 PeekMessage loop to do message processing.