::can’t start X

There’s a problem I see posted to the Ubuntu forums on a fairly regular basis that has to do with not being able to start an X session.  A user will report an error message that reads something like “no write access to /home/user/.ICEauthority…”

How does this happen?

You’ll get this error when you improperly run some graphical applications as Root.  Say you want to move some files to or from a directory in which you don’t have write access.  You fire up for favorite file manager as Root, do your stuff, and all is right with the world. 

If you’re like a lot of users, it might be days or weeks before you log out of your current X session, in which case you don’t remember performing the unhappy action above. The issue could be lurking for quite a long time, waiting for the next time you log in.

Well fear not, we can fix this in a jiffy.

From your login screen, either drop to a console session or log into failsafe.  You’ll be able to login here, but all you’ll have is a command prompt. From here, you’ll want to check the ownership of your files and try to see what Root has gone and taken ownership of.

$ ls -al |less

ls will list the contents of your directory (home, in this case), with two switches thrown in for flavor.  -a lists all files, and l (or -l if you want to do it all by itself) will give you the ownership and permissions.  Piping the command through less will pause the output a screen at time so you can actually see what you’re looking at. 

Depending on the application you ran as Root, there may be one or more files that is now owned by root.  You can take ownership of them individually, or you can reclaim ownership of all files in the directory at once.  Kind of like a dog pissing on his favorite tree.  Either way, the command is almost the same.

To reclaim ownership of an individual file:

sudo chown yourusername:yourusername filename (or in my case, something like sudo chown jim:jim .ICEauthority)

chown allows you change ownership of a file, with the first yourusername setting the user and the second yourusername setting the group. 

If you want to piss on the tree and make sure everyone knows that the whole yard is yours, simply modify the command like this:

sudo chown yourusername:yourusername *.*

Either entry will prompt you for your password–and remember–Ubuntu doesn’t enable the Root account by default, so you enter your username.

You should return to your command prompt without error.  Now you should be able to log out and log back in to your favorite X session.

And all is right with the world.

or something.

But sometimes I really want to run a graphical app as Root, what do I do?

You don’t have to fix files every time you want or need to run a graphical app as root.  If you’re using KDE, you will replace use of sudo with kdesu.  If you’re running Gnome, you’ll use gksudo instead of sudo.

so there it is…my first technical post.  Couple questions for those of you unlucky enough to come across my blog and bored enough to have read all the way down to this point:

1) Was it helpful?  If you came across this entry because you’re actually having this error, did it help you fix the problem?  Do you think it might help you in the future?

2) Was it easy to understand?

3) Was it easy to tell what was a command and what wasn’t?  Did you know what you had to enter at the command line, or did you have to muddle through the bold, italics, and bold italics until you figured out what was what?

4) What’s your favorite color?

Sometime in the next few days I’ll update the blog with some helpful links and resources I’ve found.  I know you’re giddy with anticipation now. 

kisses,

jimbo