Subject: Re: wscons and multiple wsdisplays
To: port-sparc64@NetBSD.org, <tech-kern@NetBSD.org>
From: Erik E. Fair <fair@netbsd.org>
List: tech-kern
Date: 05/18/2005 12:24:38
Once upon a time, computers were attached to "terminals" which had 
both keyboard and display on one I/O device: the serial port, so it 
was easy to associate input with the corresponding output (and vice 
versa).

Now, we have keyboards, mice, and frame buffers (or GPUs with frame 
buffers) as separate devices with no obvious association.

The degenerate case (single user) is easy: one output (even if there 
are multiple monitors, the user can see them all, right?), and all 
input gets muxed together so that you don't care where it came from 
(hence wsmux(4)).

Kerrnel configuration gets much more interesting if you want multiple 
users of a single computer (N frame buffers, N keyboards, N mice, for 
N > 1), you have to figure out a way to associate the inputs devices 
with the output devices.

It was my understanding of the discussions when wscons(4) was 
designed that it was supposed to be capable of supporting the N > 1 
case, even in the presence of  hot plug systems like USB. Is there an 
example kernel config(8) that does this?

	curious,

	Erik <fair@netbsd.org>