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PeekMessage and PostQuitMessage

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Join Date: Jan 2008

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Icebone1000 Icebone1000 is offline

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PeekMessage and PostQuitMessage

Jun 17th, 2009

Im kind confuse about how PostQuitMessage works..

Im using like this:

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case WM_CLOSE :		DestroyWindow( hWnd );	break;	//send WM_DESTROY
 
case WM_DESTROY :	CleanUp();
			gsp_quit = true;
			PostQuitMessage( 0 );			//send WM_QUIT
 
					break;
case WM_CLOSE :		DestroyWindow( hWnd );	break;	//send WM_DESTROY

case WM_DESTROY :	CleanUp();
			gsp_quit = true;
			PostQuitMessage( 0 );			//send WM_QUIT

					break;

That is on my WndProc function.

My message loop is like that:

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while ( !gsp_quit ){
 
		if( PeekMessage( &gsp_msg, NULL, NULL, NULL, PM_REMOVE ) ){
 
			TranslateMessage( &gsp_msg );
			DispatchMessage	( &gsp_msg );
 
		}//while F PeekMessage()
 
	}//F while !gsp_quit
 
	//***
 
	return gsp_msg.wParam;//it should return 0
while ( !gsp_quit ){
	
		if( PeekMessage( &gsp_msg, NULL, NULL, NULL, PM_REMOVE ) ){

			TranslateMessage( &gsp_msg );
			DispatchMessage	( &gsp_msg );

		}//while F PeekMessage()

	}//F while !gsp_quit

	//***

	return gsp_msg.wParam;//it should return 0

The problem is that it just returns 0 (zero) if I use while( PeekMessage() ) instead of 'If', or if I call PeekMessage again at //***

So, i guess theres some overheads on PostQuitMessage before it send your exit code given on its param..what are those overheads?

And where can I search for exit codes info? I was trying to find it at MSDN but I didnt..

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Join Date: Oct 2008

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adatapost

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Re: PeekMessage and PostQuitMessage

Jun 18th, 2009

Do you know the difference between GetMessage and PickMessage function?

Here is a text for you.

You can use the PeekMessage function to examine a message queue during a lengthy operation. PeekMessage is similar to the GetMessage function; both check a message queue for a message that matches the filter criteria and then copy the message to an MSG structure. The main difference between the two functions is that GetMessage does not return until a message matching the filter criteria is placed in the queue, whereas PeekMessage returns immediately regardless of whether a message is in the queue.

Failure is not fatal, but failure to change might be. - John Wooden

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Join Date: Jan 2008

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Icebone1000 Icebone1000 is offline

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Re: PeekMessage and PostQuitMessage

Jun 19th, 2009

I knew..but I think I just figure out my stupid mistake,
Im quiting the loop before proccessing the WM_QUIT( because gsp_quit became true and the message is not processed )..-_-"