Debugging X

Most likely, X started just fine for you. If you have a graphics card and monitor that were in the menus during installation and you selected them correctly, then there should be no problem. If not, then it's difficult to tell what's wrong and you may have to call technical support for whichever distribution you are using. Or you can read the FAQs listed at the end of this article. If you don't find an answer there, you can also try posting a question to the appropriate Usenet newsgroup. Diagnosing X in detail is certainly more than I can cover in this short column.

There are two commands that you can try, however, if X is not working. While logged in as "root", type Xconfigurator at the command lineprompt. This will lead you through a procedure much like the one you went through at installation, and you can try again to select your proper card and monitor.

Another useful command is XF86Setup. This one is much more powerful and gives you much better control over what you are changing. If you select the "Card" button at the top of the screen, then a "Card List" button will appear in the bottom third of the screen.

If your card is not listed, don't despair; there still might be a version of the XFree86 server available that will work for your system. When I first installed X, my graphics card was not listed, but another one with a similar name from the same manufacturer was. I selected it during the installation, but it didn't work and I found that my card was not supported. There was a new XFree86 available on Red Hat's site that did support my card, and I downloaded it. It works fine.

By the way, if you have trouble with your mouse, you can use "mouseconfig" to change your mouse setup.

The First Desktop

Now you know how to start X, how to stop it in a hurry, and how to change screen resolutions.

FIGURE 2

If you're using Red Hat Linux, your display should look something like Figure 2. There is a terminal window in the center of the screen and the "Red Hat Control Panel" along the side. On the bottom-right there's a box with a grid and a graph. The graph shows the system "load average", which is just a measure of how busy the computer is. The grid shows you which "virtual desktop" you are using. With X you can have multiple desktops available to you, with some of them hidden off screen. To select a different desktop, just click on its grid box.

Pressing each mouse button while the mouse pointer is over the background area will bring up distinct "floating" menus. Note that X originated on systems that used a mouse with three buttons, not a two-button mouse like the ones most PCs come with. The third button is not required, but can be quite useful. So, if your mouse has only two buttons, pressing both buttons together tells X that you mean the third mouse button (the one you don't have.)

If you click on the right button, a menu labeled "Programs" will come up, which has lots of useful applications and utilities in it. Clicking the middle button (or both buttons together) shows you all the windows that you currently have opened. If any are "iconized", you can reopen them through this menu. (X allows you to "iconize" windows. This means that you can close a window without quitting the program that's running in that window. Clicking on the icon will also re-open that window.)

At the bottom of the screen there's a toolbar much like the one in Windows, with a "Start" button on the left. If you click on that button you'll see the same menu that you would get if you position the mouse over the "desktop" (which is really called the "root window") and click the left mouse button (see Figure 3).

FIGURE 3

You'll find that as long as you keep the mouse pointer within the floating menu, you don't have to keep the button pressed. If you want to peruse your files, you can click the right mouse button (Programs) and move to "Utilities". Move to "File Management" in the menu that "Utilities" brought up and select "xfm". This will start the "X File Manager", which behaves a bit like Windows Explorer.

Window Managers (Part Two)

I mentioned earlier that you could change your window manager. To do this, click the left mouse button to bring up the "Start" menu. Selecting "Exit Fvwm" will bring up more options. Now select the "Switch To..." option and you should have a choice of four window managers. Each of these will look and behave a little differently. They will each have the "Switch To..." option so that you can try them all. Notice that when you change window managers, your windows remain the same; they just look different and have different menus. That's because the windows are maintained by the X server and the clients have requested that they be displayed. Changing the window manager does not affect that. The window manager only worries about the look and feel of the actual windows.

As you already know, "ctl-alt-back" is the quick way of exiting windows. The "polite" way, however, is to choose the "Exit Fvwm" option from the left mouse button (Start) menu and select the option "Yes, Really Quit".

Until Next Time...

You have now installed Linux and have X running. Find out which window manager you like and explore the utilities available. If you get yourself into trouble just get out of X (the quick way if you have to) and restart it. No need to restart the computer.

If you have Internet access and have trouble (or are just curious), you can check out http//www.xfree.org/ FAQ for help with X and http//www. linux.org/help/faq.html (or http:// www.linux.org/help/index.html) for general Linux questions. That should keep you entertained for a while. Or at least until next month.

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Hal Moroff has been developing UNIX systems and applications for 20+ years. He's new enough to Linux that he's finding new things every day. He can be reached at .