Remote display

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Revision as of 22:33, 23 February 2007 by Wad (talk | contribs) (Added caveats, and info on how to get bare X under debian)
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If you are trying to project the XO's user interface, this page describes how to do it using another computer running X11.

There may be additional refinements, these are just quick notes detailing one way of doing this.

Changes to the XO (the forwarding or source computer)

Due to current limitations of Sugar, there can only be copy of Sugar running on any given XO. This will mean that you need to shut down Sugar and X on the XO on which you want to forward your X session or display. There are several ways you can do this. There are several ways you can do this:

Change to the console (control + alt + F1) and change the runlevel of the XO to runlevel 3:

init 3

You will also need to assign a password to the olpc user on the XO. As root, run:

passwd olpc

Now change to the /home/olpc directory, and:

cd /home/olpc
cp .xinitrc remotedisplay
chmod a+x remotedisplay
vi remotedisplay

You need to add the following to the beginning of the remotedisplay file:

#!/bin/sh

Reboot (to downgrade the init level). At this point, the XO will reboot to the login prompt, but won't have networking running properly. You need to manually bring up the network using:

iwconfig eth0 essid "some local wifi SSID"
dhclient eth0

You can get a list of the local WiFi networks using iwlist. Remember the network address assigned to the XO by DHCP, you will need it for the next steps.

Bringing up the display remotely

At this point, you will need a version of X which is running bare (no display manager). The easiest way seems to be to create a new user, and give them an .xinitrc (or .xsession file under Debian) which consists simply of:

exec xterm

Log in as the new user, and from that single xterm, you should be able to bring up the display remotely using:

ssh olpc@xo-ip-address -C -X /home/olpc/remotedisplay

Caveats

Whatever you do, don't click on the WiFi signal strength when using the remote display. Even if you select the network you are already using, you will freeze the display.