xorg.conf

Xorg supports several mechanisms for supplying/obtaining configuration and run-time parameters: command line options, environment variables, the xorg.conf and xorg.conf.d configuration files, auto-detection, and fallback defaults. When the same information is supplied in more than one way, the highest precedence mechanism is used. The list of mechanisms is ordered from highest precedence to lowest. Note that not all parameters can be supplied via all methods. The available command line options and environment variables (and some defaults) are described in the Xserver (1) and Xorg (1) manual pages. Most configuration file parameters, with their defaults, are described below. Driver and module specific configuration parameters are described in the relevant driver or module manual page. where is the path specified with the −config command line option (which may be absolute or relative), $XORGCONFIG is the path specified by that environment variable (absolute or relative), $HOME is the path specified by that environment variable (usually the home directory), and is the machine’s hostname as reported by gethostname (3) . where is a relative path (with no “..” components) specified with the −configdir command line option. where is the path specified with the −configdir command line option (which may be absolute or relative). The xorg.conf and xorg.conf.d files are composed of a number of sections which may be present in any order, or omitted to use default configuration values. Each section has the form: The following obsolete section names are still recognised for compatibility purposes. In new config files, the InputDevice section should be used instead. The ServerLayout sections are at the highest level. They bind together the input and output devices that will be used in a session. The input devices are described in the InputDevice sections. Output devices usually consist of multiple independent components (e.g., a graphics board and a monitor). These multiple components are bound together in the Screen sections, and it is these that are referenced by the ServerLayout section. Each Screen section binds together a graphics board and a monitor. The graphics boards are described in the Device sections, and the monitors are described in the Monitor sections. Config file keywords are case−insensitive, and “ ” characters are ignored. Most strings (including Option names) are also case-insensitive, and insensitive to white space and “ ” characters. Each config file entry usually takes up a single line in the file. They consist of a keyword, which is possibly followed by one or more arguments, with the number and types of the arguments depending on the keyword. The argument types are: Note: hex integer values must be prefixed with “0x”, and octal values with “0”. A special keyword called Option may be used to provide free−form data to various components of the server. The Option keyword takes either one or two string arguments. The first is the option name, and the optional second argument is the option value. Some commonly used option value types include: Note that all Option values, not just strings, must be enclosed in quotes. Boolean options may optionally have a value specified. When no value is specified, the option’s value is TRUE . The following boolean option values are recognised as TRUE : When the unit name is omitted, the correct units will be determined from the value and the expectations of the appropriate range of the value. It is recommended that the units always be specified when using frequency option values to avoid any errors in determining the value. The Files section is used to specify some path names required by the server. Some of these paths can also be set from the command line (see Xserver (1) and Xorg (1) ). The command line settings override the values specified in the config file. The Files section is optional, as are all of the entries that may appear in it. Catalogue directories can be spec