The WM_DEVMODECHANGE message is sent to all top-level windows whenever the user changes device-mode settings.
WM_DEVMODECHANGE lpszDev = (LPCTSTR) lParam; // address of device name
An application should return zero if it processes this message.
Windows NT: Calls to functions that change the WIN.INI file may be mapped to the registry instead. This mapping occurs when WIN.INI and the section being changed are specified in the registry under the following keys:
HKEY_LOCAL_MACHINE\Software\Description\Microsoft\
Windows NT\CurrentVersion\IniFileMapping
The change in the storage location has no effect on the behavior of this message.