In the most recent release of Ubuntu (9.04) the developers decided (after a very lengthy discussion) that the old tried-and-true Ctrl-Al-Backspace key combination would no longer kill the X server. Their justification for this (in a nutshell) was that this combination could be accidentally hit causing the user to lose data. This was not something they wanted on their hands. To me this is a feature that I would miss. There have been instances where a poorly written application decided it needed to take up all of my memory thereby making the desktop unusable. Of course you could always go to a virtual terminal (as shown in my article "How a virtual console can keep you from losing work") but for new users this is more of a hassle than just being able to hit Ctrl-Alt-Backspace.
Now the problem with Ctrl-Alt-Backspace is that you can, in fact, lose data. But as a last resort, having this behavior back can really be helpful. And fortunately, it is possible to get the old standby behavior back. This tutorial will show you how.
There are two ways to get this behavior back into Ubuntu. You can either install the dontzap application or you can edit your /etc/X11/xorg.conf file. We'll examine both.
The dontzap application does one thing - it sets the DontZap value in xorg.conf so you don't have to. To install the application open up a terminal window and issue the following command:
sudo apt-get install dontzap
Now to set the value in your xorg.conf file you have to run the command with one of two switches:
To enable the Ctrl-Alt-Backspace behavior you use the --disable switch and to disable the Ctrl-Alt-Backspace behavior use the --enable switch. It seems backwards, but remember the command is dontzap not zap.
So the full command would be either:
sudo dontzap --enable
to disable Ctrl-Alt-Backspace. Or
sudo dontzap --disable
to enable Ctrl-Alt-Backspace.
Once you have run this command you will need to log out of X and log back in, in order for the behavior to finalize.
If you don't want to install the dontzap application you can hand-edit your xorg.conf file to include the correct DontZap entry. To do this enter the following command to open up your xorg.conf file for editing:
sudo nano /etc/X11/xorg.conf
What you want to do is add the following lines to the end of your file:
Option "DontZap" "off"
Just as you would have to using the dontzap command, you will have to log out of X and log back in for this to take effect.
There was a lot of thought and discussion that went into the decision to disable the Ctrl-Alt-Backspace behavior by default. I give the Ubuntu developers a hand for really going out on a limb and thinking more of the new end users than of the old school users like myself. I guess the developers figured it would only be a matter of time before the old school guys would figure out a way to enable this behavior on their systems.
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Ghacks is a technology news blog that was founded in 2005 by Martin Brinkmann. It has since then become one of the most popular tech news sites on the Internet with five authors and regular contributions from freelance writers.