Subject: Re: X11, wsmouse, and scroll wheels
To: Matthias Scheler <>
From: Nathan J. Williams <>
List: tech-x11
Date: 07/14/2002 03:19:58 (Matthias Scheler) writes:

> > 	    Option      "ZAxisMapping" "4 5"
> > 	would have scrollwheels working out of the box. This doesn't
> > 	seem to cause any problems to non-scrollwheel mice...
> Are there mice with five normal buttons? For these mice people woudn't
> be able to use the extra buttons any more.

There are; for example, I have a Kensington USB mouse with five
buttons and a scroll wheel. I'm not sure I can get everything to work
at all; without the ZAxisMapping line, rolling the scroll wheel does
nothing, but the two outermost buttons are 4 and 5 by default, so they
will make X applications scroll. With the ZAxisMapping line the wheel
generates button 4 and 5 events which scroll, and the outer two
buttons don't seem to get to the X event layer at all.

I believe X has a 5-button limit internally - I'll admit I don't know
whether this is fundamental to the protocol or "just" to the
programming layer, but the definitions of button-related things in X.h
only go up to 5.

        - Nathan