> >The kernel low level drivers and the userland programs that use them
> >communicate using a page of shared memory, for performance sake. This
> >page contains information such as the mouse button status
> Is that page mapped by default? Or you need to open a device to map it?

The process opens a driver, using IOKit methods (no UNIX driver open()
on a device file).

Does it helps?

-- 
Emmanuel Dreyfus
manu@netbsd.org