DWORD DefHookProc(code,wParam,lParam,lplpfnNextHook)
This function calls the next function in a chain of hook functions. A hook function is a function that processes events before they are sent to an application's message-processing loop in the WinMain function. When an application defines more than one hook function by using the SetWindowsHook function, Windows forms a linked list or hook chain. Windows places functions of the same type in a chain.
| Parameter | Type/Description |
| code | int Specifies a code used by the Windows hook function (also called the message filter function) to determine how to process the message. | |
| wParam | WORD Specifies the word parameter of the message that the hook function is processing. | |
| lParam | DWORD Specifies the long parameter of the message that the hook function is processing. | |
| lplpfnNextHook | FARPROC FAR * Points to a memory location that contains the FARPROC structure returned by the SetWindowsHook function. Windows changes the value at this location after an application calls the UnhookWindowsHook function. |
The return value specifies a value that is directly related to the code parameter.