The WM_ENTERMENULOOP message informs an application's main window procedure that a menu modal loop has been entered.
WM_ENTERMENULOOP
wParam = (BOOL) fIsTrackPopupMenu // flags a shortcut menu
lParam = 0 ; // not used; must be zero
An application should return zero if it processes this message.
The DefWindowProc function returns zero.
Windows NT: Requires version 3.1 or later.
Windows: Requires Windows 95 or later.
Windows CE: Requires version 1.0 or later.
Header: Declared in winuser.h.
Menus Overview, Menu Messages, DefWindowProc, WM_EXITMENULOOP