Living With Software: Ubuntu 11.04 (Day Four)

Well, to be honest, I did not use the computer much at all on Day 4 as I had other real life commitments. I did however make a big breakthrough in fixing the annoyingly possessed mouse cursor issue I experienced on my Dell Latitude XT tablet. Thanks to the awesome folks over at the Desktop Linux Reviews forum (I don’t shamelessly plug these guys enough. If you’re interested in getting started with Linux-anything, I can wholeheartedly recommend you check them out as they are an awesome community), I was able to refine my “google-fu” enough to find possible solutions.

Unfortunately, there is not much information yet regarding the Dell Latitude XT (or any laptop for that matter) and Ubuntu 11.04 specifically. Most of the forum threads and blog postings that I was able to find addressed mouse issues with Ubuntu 10.10. At first I was led to believe that it was the IBM-esque eraser pointer/TrackPoint pointing stick that was causing the seemingly random mouse drifting and clicking. People even went so far as to open up the computer and disconnect the TrackPoint’s ribbon cable. Before voiding the warranty and cracking open my computer, I decided to do some more testing. Thanks to a bit of luck and trial and error, I was able to figure out that the terminal command “xinput” would list all the input devices connected to the laptop. I then included that in my Google searches and found a forum post recommending me to use the “set-prop” aspect of the command to turn an input device off. I then turned off the TrackPoint. No luck, the mouse still spazzed out. I then turned off the TrackPad, but again no luck. Turning off the Pen also did nothing to fix the issue. I then determined that the problem had to be with the multitouch/touch drivers. I turned off the multitouch device… and the issue was gone! Finally!

Unfortunately, this is one of the drawbacks of Linux. That same powerful nature that results from a 1:1 CLI to GUI setup also makes it extremely difficult to people used to the way Windows operates to fix problems without help of those more versed in the ways of Linux. Things are improving though, slowly but surely. I still like Ubuntu and will continue to mess around with Linux. Without user adoption, their’s no hope of documentation and ease of use improvements ;). When Linux works, it does work well so I’m not going to mark this Ubuntu release down much even though the issue was extremely annoying.

Speaking of better documentation, if you’re running into mouse cursor errors on the Dell Latitude XT in Ubuntu 11.04, I’d encourage you to try the above mentioned steps of using xinput and turning each device off and on in turn to narrow down the culprit. If it turns out to be the touchscreen as is the case with my machine, here is how to fix it. Note that using xinput will only disable the input device for the current session. The setting is not persistent across log-ins without a small tweak which I’ll detail below.

So here goes:

You’ll need to log into Ubuntu and start up the terminal. If you are using Unity, click the Application button, search for “Terminal” and hit enter. You will now need to enter commands. Type or copy and paste the following commands (so only the light blue text). When you see (Enter), this means you need to hit enter (do not type (enter) ).

xinput list (Enter)

This will bring up a list of input devices in your terminal. Find the ID of the “N-Trig Multitouch” device. Now type:

xinput set-prop ID “Device Enabled” 0 (Enter)

This will fix the problem long enough for you to perform the persistent fix. Now that the mouse is under control, type:

cd (Enter)

gedit notouch (Enter)

A new window will appear. In this new window, type:

#!/bin/bash (Enter)

xinput set ‘N-Trig MultiTouch’ ‘Device Enabled’ 0 (Enter)

Now save that file.

Go back to the terminal window you were using previously and enter:

chmod 744 notouch (Enter)

Now close the terminal window. Navigate to System>Preferences>Startup Applications if you are using the classic interface or the Power/Log-out menu>System Settings>Startup Applications (you can search for Startup in the search box if you can not see it in the list). Once you have a window of all the startup applications on your system, hit the “Add” button. You’ll then be presented with a dialog box asking for a Name, Command, and Comment. In name field, enter “Touch Off”. In the Command field, browse to and select the “notouch” file that you created earlier in the gedit window. It should be located in your user’s home folder. In the Comment field, enter something helpful such as “Turns off touch input”. Save your settings.

Now, everytime you log out and back in (or restart), your xinput setting will be automatically applied. While this fix is by no means pretty, it does work well. I hope that it helps someone. If you are not confident in creating a “notouch” file, you can download the one I created here. You will need to mark that file as executable once you’ve downloaded it (either using the chmod 744 terminal command as above or right clicking the file and setting the permissions in the GUI. Then follow the instructions for opening the Startup Applications and adding the notouch file.

I hope that this helps someone