Xorg.conf - Red Hat ENTERPRISE LINUX 5 - DEPLOYMENT Deployment Manual

Chapter 31. The X Window System
To load optional modules, they must be specified in the X server configuration file, /etc/X11/
xorg.conf. For more information about loading modules, refer to
When Red Hat Enterprise Linux 5.2 is installed, the configuration files for X are created using
information gathered about the system hardware during the installation process.

31.3.1. xorg.conf

While there is rarely a need to manually edit the /etc/X11/xorg.conf file, it is useful to understand
the various sections and optional parameters available, especially when troubleshooting.
31.3.1.1. The Structure
The /etc/X11/xorg.conf file is comprised of many different sections which address specific
aspects of the system hardware.
Each section begins with a Section "<section-name>" line (where <section-name> is the title
for the section) and ends with an EndSection line. Each section contains lines that include option
names and one or more option values. These are sometimes enclosed in double quotes (").
Lines beginning with a hash mark (#) are not read by the X server and are used for human-readable
comments.
Some options within the /etc/X11/xorg.conf file accept a boolean switch which turns the feature
on or off. Acceptable boolean values are:
• 1, on, true, or yes — Turns the option on.
• 0, off, false, or no — Turns the option off.
The following are some of the more important sections in the order in which they appear in a typical
/etc/X11/xorg.conf file. More detailed information about the X server configuration file can be
found in the xorg.conf man page.
31.3.1.2. ServerFlags
The optional ServerFlags section contains miscellaneous global X server settings. Any settings
in this section may be overridden by options placed in the ServerLayout section (refer to
Section 31.3.1.3, "ServerLayout"
Each entry within the ServerFlags section is on its own line and begins with the term Option
followed by an option enclosed in double quotation marks (").
The following is a sample ServerFlags section:
Section "ServerFlags" Option "DontZap" "true" EndSection
The following lists some of the most useful options:
• "DontZap" "<boolean>" — When the value of <boolean> is set to true, this setting prevents
the use of the Ctrl+Alt+Backspace key combination to immediately terminate the X server.
• "DontZoom" "<boolean>" — When the value of <boolean> is set to true, this setting
prevents cycling through configured video resolutions using the Ctrl+Alt+Keypad-Plus and
Ctrl+Alt+Keypad-Minus key combinations.
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for details).
Section 31.3.1.5, "Module".