Task Manager technic

Hey guys,

From my understanding when your closing a window from Task Manager, it sends a WM_CLOSE or WM_QUIT (not sure). So I used : SendMessageA(hWin,WM_CLOSE,0,0); and it worked, but unfortunately it didn't work on my other window. It works when I close it from Task Manager but not from sending a SendMessage. So can anyone tell me the way that task manager closes windows and help me out with the coding thanks.

If you opened another window such as a child window, close those windows first then close the main program's window.

Thanks, but theres not child window. It's kinda weird because when I close it with Task Manager it works. When I send a SendMessage it doesn't work. Does Task Manager work by sending a SendMessage?

There are several messages sent when a window is beign closed. WM_QUIT, WM_DESTROY are the two most common. Typically you would want to PostMessage() , not SendMessage(). Post a WM_DESTROY message to the appropriate HWND then post a WM_QUIT to the same HWND and the application should exit.

I tried doing PostMessage(hWin,WM_DESTROY,0,0);
PostMessage(hWin,WM_QUIT,0,0);

It tried using this on another window it worked, but when I tried on my desired window it didn't work. Is there any program that can tell me if the application received the command?

There's a program, Spy++, that comes with Visual Studio. It allows you to monitor all messages a program receives.

You could monitor an application and then close it through task manager to find out what it does.

Quote:

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Originally Posted by NoFearXD

I tried doing PostMessage(hWin,WM_DESTROY,0,0);
PostMessage(hWin,WM_QUIT,0,0);

It tried using this on another window it worked, but when I tried on my desired window it didn't work. Is there any program that can tell me if the application received the command?

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There's also WM_CLOSE.
If messages don't work, try ExitProcess() then on last resort do TerminateProcess().

Well thanks guys, but this guy from msdn forum replied and told me that Task Manager uses "EndTask" to close the window. So I looked it up in msdn http://msdn2.microsoft.com/en-us/library/ms633492.aspx but when I compile it says 'EndTask' : undeclared identifier. I included windows.h and it doesn't work. Any help here?

And Queatrix thanks but I really don't want to use those. I hope the EndTask will eventually work.

Why don't you read the whole page?

Quote:

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Originally Posted by http://msdn2.microsoft.com/en-us/library/ms633492.aspx

Remarks

Although you can access this function by using LoadLibrary and GetProcAddress combined in Microsoft Windows versions prior to Windows XP, the function is not accessible using the standard Include file and library linkage. The header files included in Windows XP Service Pack 1 (SP1) and Windows Server 2003 document this function and make it accessible using the appropriate Include file and library linkage. However, this function is not intended for general use. It is recommended that you do not use it in new programs because it might be altered or unavailable in subsequent versions of Windows. a

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>> And Queatrix thanks but I really don't want to use those.
>> I hope the EndTask will eventually work.

You may have to though, as the window your closing may be locked up.

Yup, your right, I used this tool http://www.diamondcs.com.au/index.php?page=apt to see what method was working, and EndTask didn't but TerminateProcess did. But I don't understand how come its working since you need to have the process handle which you get by using OpenProcess, but in my case OpenProcess is hooked and returns an error.

Never call TerminateProcess on anything unless you
a) encounter a critical error in your own application and need to terminate it or
b) you know the target application cannot close normally.

TerminateProcess is brutal and will e.g. not allow the program to ask the user to save data.