The system broadcasts the DBT_DEVNODES_CHANGED device event when a device has been added to or removed from the system. Applications that maintain lists of devices in the system should refresh their lists.
To broadcast this device event, the system uses the WM_DEVICECHANGE message with wParam set to DBT_DEVNODES_CHANGED and lParam set to zero.
LRESULT CALLBACK WindowProc( HWND hwnd, // handle to window UINT uMsg, // WM_DEVICECHANGE WPARAM wParam, // device-change event LPARAM lParam // event-specific data );
A handle to a window.
The WM_DEVICECHANGE message identifier.
Set to DBT_DEVNODES_CHANGED.
Set to zero.
There is no additional information about which device has been added to or removed from the system. Applications that require more information should register for device notification using the RegisterDeviceNotification function.
Minimum supported client
Minimum supported server
|Windows Server 2003|