Returns a handle to the active window when it has changed or when its title contains a given string. Can be used to wait until a certain window or dialog becomes active.
title - STRING* or char*, part of the window title, or NULL for returning the handle only when the active window has changed.
HWND of the active window when it either partially matches the given title, or has changed since the last sys_active call. Otherwise, NULL.
- Normally the engine window is the active window, unless another application was started with exec or a Windows dialog became active.