Exit function question...MFC

Anyone know which mfc function is called when exiting via the "x" in top right?

No MFC exit function is called when an application is exited by clicking the (X) button. Instead a WM_QUIT message is posted in the message queue in the "WM_CLOSE" message handler of the main window. On encountering the WM_QUIT message, the message loop is exited and the control is returned to the OS.

Ok, that makes sense...but gives rise to two more questions. Is the same message posted with a double-click on the upper-right corner icon? If so, is it possible to override the process so that a mfc function IS called? We are having memory leaks on exit if not through the file-->exit menu path...Any and all help will be greatly appreciated...

Double-clicking the icon in the top-left or the cross in the top-right routes through WM_SYSCOMMAND (OnSysCommand() ) with an ID of SC_CLOSE. It then goes through WM_CLOSE, WM_DESTROY (OnDestroy() ) and WM_QUIT. The best place to catch this is OnDestroy(), because closing the window via any means (including File - Exit) goes through that route (since the window is always destroyed!) If this routine is not called, this is one reason for memory leaks - a window is not being destroyed.

When your program exits, DevStudio usually lists the leaks and the lines at which the leaked objects were created. Although this isn't 100% useful, it may help to remove many of the problems.

A common source of leaks is resources - calling GetXXX() but not ReleaseXXX(), or CreateXXX() but not DeleteXXX(), etc.

Thanks...I think that will help...(I'm completely new to windows programming, so I truly do appreciate it...)