| LRESULT CALLBACK WindowProc(hwnd, msg, wParam, lParam) | |||||
| HWND hwnd; | /* handle of window, */ | ||||
| UINT msg; | /* message | */ | |||
| WPARAM wParam; | /* first message parameter | */ | |||
| LPARAM lParam; | /* second message parameter | */ | |||
The WindowProc function is an application-defined callback function that processes messages sent to a window.
hwnd
Identifies the window.
msg
Specifies the message.
wParam
Specifies 16 bits of additional message-dependent information.
lParam
Specifies 32 bits of additional message-dependent information.
The return value is the result of the message processing. The value depends on the message being processed.
The WindowProc name is a placeholder for the application-defined function name. The actual name must be exported by including it in an EXPORTS statement in the application's module-definition file.