REFERENCE GUIDE

WM_QUERVENDSESSIONWM_QUERYENDSESSIONThis message is sent when the user chooses the End Session command. Ifany application returns zero, the session is not ended. Windows stopssending WM_QUERYENDSESSION messages as soon as one applicationreturns zero, and sends WM_ENDSESSION messages, with the wParamparameter set to zero, to any applications that have already returnednonzero.Parameters wParam Is not used.Return valueDefault actionIParamIs not used.The return value is nonzero if the application can be conveniently shutdown. Otherwise, it is zero.The DefWindowProc function returns nonzero.WM_ QU ERYN EWPALETIE 3.0This message informs a window that it is about to receive input focus. Ifthe window realizes its logical palette when it receives input focus, thewindow should return TRUE; otherwise, it should return FALSE.Parameters wParam Is not used.Return valueIParamIs not used.The return value is TRUE if the window realizes its logical palette.Otherwise, it is FALSE.This message is sent to an icon when the user requests that it be openedinto a window.Parameters wParam Is not used.Return valueDefault actionIParamIs not used.The return value is zero when the application prevents the icon frombeing opened. It is nonzero when the icon can be opened.The DefWindowProc function returns nonzero.Chapter 6, Messages directory 681