Chapter 7. The X Window System
While the heart of Red Hat Enterprise Linux is the kernel, for many users, the face of the
operating system is the graphical environment provided by the X
Window System, also called X.
Various windowing environments have existed in the
UNIX™ world for decades, predating many of the
current mainstream operating systems. Through the years, X has become the
dominant graphical environment for UNIX-like operating systems.
The graphical environment for Red Hat Enterprise Linux is supplied by the X.Org
Foundation, an open source consortium created to manage
development and strategy for the X Window System and related
technologies. X.Org is a large scale, rapidly developing project with
hundreds of developers around the world. It features a wide degree of
support for a variety of hardware devices and architectures, and can run on
a variety of different operating systems and platforms. This release for
Red Hat Enterprise Linux specifically includes the X11R6.8 release of the X Window System.
The X Window System uses a client-server architecture. The X
server (the Xorg binary) listens for
connections from X client applications via a
network or local loopback interface. The server communicates with the
hardware, such as the video card, monitor, keyboard, and mouse. X client
applications exist in the user-space, creating a graphical user
interface (GUI) for the user and
passing user requests to the X server.
Red Hat Enterprise Linux 4 uses the X11R6.8 release as the base X Window
System, which includes many cutting edge X.Org technology enhancements,
such as 3D hardware acceleration support, the XRender extension for
anti-aliased fonts, a modular driver-based design, and support for
modern video hardware and input devices.
 | Important |
|---|
| | Red Hat Enterprise Linux no longer provides the XFree86™ server
packages. Before upgrading to the latest version of Red Hat Enterprise Linux, be sure
that the video card is compatible with the X11R6.8 release by checking
the Red Hat Hardware Compatibility List located online at https://hardware.redhat.com/.
|
The files related to the X11R6.8 release reside primarily in two locations:
- /usr/X11R6/
Contains X server and some client applications, as well as X header
files, libraries, modules, and documentation.
- /etc/X11/
Contains configuration files for X client and server
applications. This includes configuration files for the X server
itself, the fs font server, the X
display managers, and many other base components.
It is important to note that the configuration file for the
newer Fontconfig-based font architecture is
/etc/fonts/fonts.conf (which obsoletes the
/etc/X11/XftConfig file). For more on
configuring and adding fonts, refer to Section 7.4 Fonts.
Because the X server performs advanced tasks on a wide array of
hardware, it requires detailed configuration. The installation program
installs and configures X automatically, unless the X11R6.8 release
packages are not selected for installation. However, if the monitor or
video card changes, X must to be reconfigured. The best way
to do this is to use the X Configuration Tool
(system-config-display).
To start the X Configuration Tool while in an
active X session, go to the (on the
Panel) => =>
. After using the
X Configuration Tool during an X session, changes
takes effect after logging out and logging back in. For more about
using the X Configuration Tool, refer to the chapter
titled X Window System Configuration in the
Red Hat Enterprise Linux System Administration Guide.
In some situations, reconfiguring the X server may require
manually editing its configuration file,
/etc/X11/xorg.conf. For information about the
structure of this file, refer to Section 7.3 X Server Configuration Files.
