The X Window System
What Is (And Isn't) X Eons ago computer terminals came with a screen and a keyboard and not much else. Mice hadn't come into common use and everything was menu driven. Then came the Graphical User Interface (GUI) and the world was changed. Today users are accustomed to moving a mouse around a screen, clicking on icons and running tasks with fancy images and animation, but UNIX systems predated this and so GUIs were added almost as an afterthought. For many years, Linux and its UNIX brethren were primarily used without graphics of any sort, but today it is perhaps more common than not for users to prefer their Linux computers come with shiney, flashy, clickable GUIs, and all these GUIs run on X(7). So what is X? Is it the desktop with the icons? Is it the menus? Is it the window manager? Does it mark the spot? The answer to all these is a resounding "no". There are many parts to a GUI, but X is the most fundamental. X is that application that receives input from the mouse, keyboard, and possibly other devices. X is that application that tells the graphics card what to do. In short, X is the application that talks to your computer's hardware from graphical purposes; all other graphical applications simply talk to X. Let's stop for a moment and talk about nomenclature. X is just one of a dozen names that you may encounter. It is also called X11, the X Window System, X Window, X11R6, X Version 11, and several others. Whatever you hear it called, simply understand that the speakers are referring to X.
Configuring the X Server As powerful as Slackware Linux is, configuring X can be daunting and is often one of the first real challenges a new user faces. Don't be overly concerned if you find this a bit difficult. While many changes have been made over the years that make this much easier, there are still computers out there that don't properly auto-detect, or you'll wish to make some change to some setting and it might not be immediately apparent what to do. Just remember that when I started using X, it was far more primitive than it is today, took far more work to configure, and often crashed without telling the user what was wrong. If I and thousands of others got this working back then, you can do it today. Fortunately, with X.Org 1.6.3 an /etc/X11/xorg.conf does not even need to be present for X to attempt a working display, further, Slackware includes a default configuration file that works for most computers by using the VESA standard. This offers only the most basic functions and may not allow your graphics card to operate at its full potential. You may be limited to low resolutions, fewer colors, and X will be slower. Still, this is an option for users, particularly those who only want to occassionally run X. You can try it out now simply by running startx(1) from a command prompt. There are many ways to configure X, but the easiest is to use xorgsetup. This will attempt to probe probe your computer's hardware and write a working xorg.conf file. This option is not garaunteed to work; there are some platforms that it is known not to work with, and there are probably others as well. Still, it is worth trying first as it is the quickest and least complicated for a new user to attempt. The second most popular way to configure X on your system is the handy xorgconfig(1). This application asks you a series of questions about your computer's hardware and writes out a config file based on your choices. Unless you know exactly what your hardware is, we recommend that you try xorgsetup first. Additionally, the X has flags available to let X attempt to detect hardware and render an xorg.conf.new that should work with the hardware present. From a virtual terminal call X -configure, and the resulting file will be either /root/xorg.conf.new or $HOME/xorg.conf.new. Before moving this new configuration to /etc/X11/, it can be tested by calling X -config /root/xorg.conf.new, then you can exit this X session with <CTRL>+<ALT>+<Backspace>. Lastly, you can manually configure your X server by modifying /etc/X11/xorg.conf with a text editor. This is not normally a task for the faint of heart, but is often the easiest way to make minor changes.
Choosing a Window Manager Slackware Linux includes many different window managers and desktop environments. Window managers are the applications responsible for painting application windows on the screen, resizing these windows, and similar tasks. Desktop environments include a window manager, but also add task bars, menus, icons, and more. Slackware includes both the KDE and XFCE desktop environments and several additional window managers. Which you use is entirely your own decision, but in general, window managers tend to be faster than desktop environments and more suitable to older systems with less memory and slower processors. Desktop environments will be more comfortable for users accustomed to Microsoft Windows. The easiest way to choose a window manager is xwmconfig(1), included with Slackware Linux. This application allows a user to choose what window manager to run with startx.
Setting Up A Graphical Login By default, when you boot your Slackware Linux system you are presented with a login prompt on a virtual terminal. This is more than adequate for most people's needs. If you need to run commandline applications, you may login and do so right away. If you want to run X, simply executing startx will do that for you nicely. But suppose you almost exclusively use your system for graphical duties like many laptop owners? Wouldn't it be nice for Slackware to take you straight into a GUI? Fortunately, there's an easy way to do just that. Slackware uses the System V init system which allows the administrator to boot into or change to different runlevels, which are really just different "states" the computer can be in. In fact, shutting down the computer is really only a case of changing to a runlevel which accomplishes just that. Runlevels can be rather complicated, so we won't delve into them any further than necessary. Runlevels are configured in inittab(5). The most common ones are runlevel 3 (Slackware's default) and runlevel 4 (GUI). In order to tell Slackware to boot to a GUI screen, simply open /etc/inittab with your favorite editor of choice. (You may wish to refer to one of the chapters on vi or emacs at this point.) Near the top, you'll see the relevant entries. # These are the default runlevels in Slackware: # 0 = halt # 1 = single user mode # 2 = unused (but configured the same as runlevel 3) # 3 = multiuser mode (default Slackware runlevel) # 4 = X11 with KDM/GDM/XDM (session managers) # 5 = unused (but configured the same as runlevel 3) # 6 = reboot # Default runlevel. (Do not set to 0 or 6) id:3:initdefault: In this file (along with most configuration files) anything following a hash symbol # is a comment and not interpreted by init(8). Don't worry if you don't understand everything about inittab, as many veteran users don't either. The only line we are interested in is the last on above. Simply change the 3 to a 4 and reboot. # These are the default runlevels in Slackware: # 0 = halt # 1 = single user mode # 2 = unused (but configured the same as runlevel 3) # 3 = multiuser mode (default Slackware runlevel) # 4 = X11 with KDM/GDM/XDM (session managers) # 5 = unused (but configured the same as runlevel 3) # 6 = reboot # Default runlevel. (Do not set to 0 or 6) id:4:initdefault: