Rewlad's links

Hi,

I have dual-head ATI card and want to configure dual-seat for me and Vika.
So that when working alone to use 2 monitors, but when she comes to give the second one to her.
Usually multi-seat implies display manager configuration and multiply instances of Xorg server.
But there was problem to share the card between servers,
and no really need to maintain security between me and her.

So I found, that nested X server can be used here.
Nested X server is a (fullscreen) client of the main one.
Second keyboard and mouse need to be used by the nested server and ignored by the main one

------- actions -------------------------------------------------------------
configure the card, 2 screens for single user, and restart to apply changes:
$ aticonfig --initial=dual-head --resolution=1,1024x768
$ servise gdm restart
install xserver-xephyr
see, what input devices do we have:
$ hal-device
compose /etc/hal/fdi/policy/input.fdi to disable chosen devices
restart hal
replug devices
add .../bin/Xep.sh
use or make shortcut with gksu:
$ sudo Xep.sh
---------- input.fdi -----------------------------------------------------------
<?xml version="1.0" encoding="UTF-8"?>
<deviceinfo version="0.2">
<device>
<match key="info.capabilities" contains="input.mouse">
<match key="info.product" contains="Converter">
<merge key="input.x11_driver" type="string"></merge>
</match>
</match>
<match key="info.capabilities" contains="input.keys">
<match key="info.product" contains="Converter">
<merge key="input.x11_driver" type="string"></merge>
</match>
</match>
</device>
</deviceinfo>
------------- Xep.sh -----------------------------------------------------------
#!/bin/bash
DISPLAY=:0.1
Xephyr :1 -fullscreen \
-mouse evdev,,device=/dev/input/by-id/usb-Composite_USB_PS2_Converter_USB_to_PS2_Adaptor_v1.12-event-mouse \
-keybd evdev,,device=/dev/input/by-id/usb-Composite_USB_PS2_Converter_USB_to_PS2_Adaptor_v1.12-event-kbd &
DISPLAY=:1
DBUS_SESSION_BUS_ADDRESS=''
HOME=/home/vika
sleep 2
sudo -u vika startkde
-------------- explain ---------------------------------------------------------
in .fdi we need to reset input.x11_driver from 'evdev' to '',
so Xorg will ignore the device

:0.1 is xserver_number.screen_number --
Xephyr starts as client on :0.1 (main Xorg server) and then serves on :1

/dev/input/eventX are changing,
.../by-id/...-event-... are stable (at least if all devices are different)

kde needed DBUS_SESSION_BUS_ADDRESS and HOME reset and delay to start

test xephyr with input devices by:
$ xeyes -display :1

not yet seen, what is #XAUTHORITY="/var/lib/gdm/:0.Xauth"

not yet able to stop xephyr without killall

not yet tried: xfce4-session

also useful:
cat /proc/bus/input/devices

--------- links ----------------------------------------------------------------

idea to use xephyr for multiseat:
http://netpatia.blogspot.com/search/label/multiseat

xephyr mouse options:
http://lists.freedesktop.org/archives/xorg/2008-November/040253.html

mdm ready solution (not tried):
http://wiki.c3sl.ufpr.br/multiseat/index.php/Live-CD

very good story about xorg, hal, fdi:
http://who-t.blogspot.com/2008/07/input-configuration-in-nutshell.html