Changing Window Procedure

[vinayak4gargya]

Hi
Is this code for changing an application's window procedure correct , cuz im having trouble with it

while(TRUE)
	{
	hwnd = GetForegroundWindow();
	if((WNDPROC)GetWindowLong(hwnd,GWL_WNDPROC) != NULL)
		OldWindowProc = (WNDPROC)GetWindowLong(hwnd,GWL_WNDPROC);
	SetWindowLong(hwnd,GWL_WNDPROC,(LONG)fakeWinProc);
	Sleep(5000);
	}

[Skizmo]

cuz im having trouble with it

What's the trouble ?

[vinayak4gargya]

well basically i want to log all keystroke events...
From the debugger it is evident that i get the foreground window... (a call to showwindow(hwnd,SW_HIDE) works)
But the keystroke events in wndproc are not logged.. And the value in the OldWndProc is always 0x0000000.

[Chris_F]

Have you looked into SetWindowsHookEx? If a keyboard hook is what you want, then why not set it up the usual way?

[Igor Vartanov]

From the debugger it is evident that i get the foreground window... (a call to showwindow(hwnd,SW_HIDE) works)...
But the keystroke events in wndproc are not logged.. And the value in the OldWndProc is always 0x0000000.

I presume the said code is executed in some process other than the foreground window belongs to. Well, to do that correct, the new window procedure must reside in the window's process. Otherwise the quoted code makes no sense.

well basically i want to log all keystroke events...

Well basically they do that some other way...

[vinayak4gargya]

oooh thanks a lot! So i need to hook into a process first?? Could somebody please elaborate on 'hooking'.. Or link to an article probably?

[VictorN]

Hooks