Xterm works find under root but getting error on other accounts.
 

I recently setup FC3 on my computer at home. I have a 700 Mghz computer I built myself. My problem is that I have decided to set it up as a server running Linux. I have been trying to install Oracle 9i on it and it lead me to a problem I am having with xterm under accounts other than root. When I am logged in as root, xterm works just fine. When I try to run it as any other account (after I have suse'd into it), I get the error unable to open display "localhost:0.0". Do I need to log in as the other account from the login screen to make it work?

As a security feature, X11 does not allow other users to start a window in an active display.

As a simple example of why this is a good idea imagine a malicious user starting up a Firefox browser pointed at a porn site on *your* X11 screen just as your boss walked past.

There are ways to disable this feature, but the best things to do are:

(a) Not log into X as root, it's bad for security

(b) Start up a new Xterm and use the "su" command to switch to the other user when necessary.

Thanks. Of course right now, this machine does not have access to the internet but I hope to have that issue resolved soon also. I will keep that in mind. Of course the instructions I had for installing Oracle said to SU in as the oracle id. I will try logging in as another account and see how that goes.

Of course, if you do want other users to be able to pop up windows in your X session then you can do this from a terminal: