From mboxrd@z Thu Jan  1 00:00:00 1970
Date: Sun,  1 Dec 1996 14:09:21 +0000
From: miller@hamnavoe.demon.co.uk miller@hamnavoe.demon.co.uk
Subject: 3-button mice and clearing dtr
Topicbox-Message-UUID: 52e8f45e-eac8-11e9-9e20-41e7f4b1d025
Message-ID: <19961201140921.azhfblCGsl1TRh3YNDuVbvUwS6uF-gvzY4ijcjkMYH4@z>

If your mouse is like mine, and reverts to 2-button behaviour
if dtr is reasserted, you'll find that the suggestion from
forsyth@plan9.cs.york.ac.uk:

> change aux/mouse.c
>
> add a timedwrite(ctl, "d0", 2)

doesn't do the trick.  aux/mouse finishes by writing a "serial ..."
command to /dev/mousectl, which causes the kernel to raise dtr
and then lock the serial port so it can't be changed again.

A sensible solution would probably require adding a new parameter
to aux/mouse, and to routines serialmouse() and uartspecial() in the
kernel.  Or buying a proper three-button mouse.

A quicker and dirtier way is:

1. Insert at the end of uartspecial() in /sys/src/9/pc/devuart.c:
		{ char *p;
		  if (iq == &mouseq && (p = getconf("mousedtr")))
			uartdtr(up, strtoul(p, 0, 0));
		}
   and rebuild the kernel.

2. Insert into the plan9.ini configuration file the line
		mousedtr=0

3. In the /bin/termrc shell script, replace the line
		aux/mouse $mouseport
   with
		echo serial$mouseport >'#b/mousectl'

This works for me.

-- Richard Miller