xorg.conf(5) (xorg-server 1.20.11) xorg.conf(5)
NAME
xorg.conf, xorg.conf.d - configuration files for Xorg X
server
INTRODUCTION
Xorg supports several mechanisms for supplying/obtaining
configuration and run-time parameters: command line options,
environment variables, the xorg.conf and xorg.conf.d config-
uration 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 avail-
able 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.
DESCRIPTION
Xorg uses a configuration file called xorg.conf and files
ending in the suffix .conf from the directory xorg.conf.d
for its initial setup. The xorg.conf configuration file is
searched for in the following places when the server is
started as a normal user:
/etc/X11/<cmdline>
/usr/etc/X11/<cmdline>
/etc/X11/$XORGCONFIG
/usr/etc/X11/$XORGCONFIG
/etc/X11/xorg.conf
/etc/xorg.conf
/usr/etc/X11/xorg.conf.<hostname>
/usr/etc/X11/xorg.conf
/usr/lib/X11/xorg.conf.<hostname>
/usr/lib/X11/xorg.conf
where <cmdline> is a relative path (with no lq..rq components)
specified with the -config command line option, $XORGCONFIG
is the relative path (with no lq..rq components) specified by
that environment variable, and <hostname> is the machine's
hostname as reported by gethostname(3).
When the Xorg server is started by the lqrootrq user, the con-
fig file search locations are as follows:
<cmdline>
/etc/X11/<cmdline>
/usr/etc/X11/<cmdline>
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$XORGCONFIG
/etc/X11/$XORGCONFIG
/usr/etc/X11/$XORGCONFIG
/etc/X11/xorg.conf
/etc/xorg.conf
/usr/etc/X11/xorg.conf.<hostname>
/usr/etc/X11/xorg.conf
/usr/lib/X11/xorg.conf.<hostname>
/usr/lib/X11/xorg.conf
where <cmdline> is the path specified with the -config com-
mand line option (which may be absolute or relative),
$XORGCONFIG is the path specified by that environment vari-
able (absolute or relative), $HOME is the path specified by
that environment variable (usually the home directory), and
<hostname> is the machine's hostname as reported by
gethostname(3).
Additional configuration files are searched for in the fol-
lowing directories when the server is started as a normal
user:
/etc/X11/<cmdline>
/etc/X11/<cmdline>
/etc/X11/xorg.conf.d
/etc/X11/xorg.conf.d
where <cmdline> is a relative path (with no lq..rq components)
specified with the -configdir command line option.
When the Xorg server is started by the lqrootrq user, the con-
fig directory search locations are as follows:
<cmdline>
/etc/X11/<cmdline>
/etc/X11/<cmdline>
/etc/X11/xorg.conf.d
/etc/X11/xorg.conf.d
where <cmdline> is the path specified with the -configdir
command line option (which may be absolute or relative).
Finally, configuration files will also be searched for in a
directory reserved for system use. This is to separate con-
figuration files from the vendor or 3rd party packages from
those of local administration. These files are found in the
following directory:
/usr/share/X11/xorg.conf.d
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
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use default configuration values. Each section has the
form:
Section 34SectionName34
SectionEntry
...
EndSection
The section names are:
Files File pathnames
ServerFlags Server flags
Module Dynamic module loading
Extensions Extension enabling
InputDevice Input device description
InputClass Input class description
OutputClass Output class description
Device Graphics device description
VideoAdaptor Xv video adaptor description
Monitor Monitor description
Modes Video modes descriptions
Screen Screen configuration
ServerLayout Overall layout
DRI DRI-specific configuration
Vendor Vendor-specific configuration
The following obsolete section names are still recognised
for compatibility purposes. In new config files, the
InputDevice section should be used instead.
Keyboard Keyboard configuration
Pointer Pointer/mouse configuration
The old XInput section is no longer recognised.
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 moni-
tors are described in the Monitor sections.
Config file keywords are case-insensitive, and lq_rq charac-
ters are ignored. Most strings (including Option names) are
also case-insensitive, and insensitive to white space and
lq_rq characters.
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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:
Integer an integer number in decimal, hex or octal
Real a floating point number
String a string enclosed in double quote marks (34)
Note: hex integer values must be prefixed with lq0xrq, and
octal values with lq0rq.
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 argu-
ment is the option value. Some commonly used option value
types include:
Integer an integer number in decimal, hex or octal
Real a floating point number
String a sequence of characters
Boolean a boolean value (see below)
Frequency a frequency value (see below)
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 fol-
lowing boolean option values are recognised as TRUE:
1, on, true, yes
and the following boolean option values are recognised as
FALSE:
0, off, false, no
If an option name is prefixed with 34No34, then the option
value is negated.
Example: the following option entries are equivalent:
Option 34Accel34 34Off34
Option 34NoAccel34
Option 34NoAccel34 34On34
Option 34Accel34 34false34
Option 34Accel34 34no34
Frequency option values consist of a real number that is
optionally followed by one of the following frequency units:
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Hz, k, kHz, M, MHz
When the unit name is omitted, the correct units will be
determined from the value and the expectations of the appro-
priate 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.
FILES SECTION
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.
The entries that can appear in this section are:
FontPath 34path34
sets the search path for fonts. This path is a comma
separated list of font path elements which the Xorg
server searches for font databases. Multiple
FontPath entries may be specified, and they will be
concatenated to build up the fontpath used by the
server. Font path elements can be absolute directory
paths, catalogue directories or a font server identi-
fier. The formats of the later two are explained
below:
Catalogue directories:
Catalogue directories can be specified using the
prefix catalogue: before the directory name. The
directory can then be populated with symlinks
pointing to the real font directories, using the
following syntax in the symlink name:
<identifier>:[attribute]:pri=<priority>
where <identifier> is an alphanumeric identifier,
[attribute] is an attribute which will be passed
to the underlying FPE and <priority> is a number
used to order the fontfile FPEs. Examples:
75dpi:unscaled:pri=20 -> /usr/share/X11/fonts/75dpi
gscript:pri=60 -> /usr/share/fonts/default/ghostscript
misc:unscaled:pri=10 -> /usr/share/X11/fonts/misc
Font server identifiers:
Font server identifiers have the form:
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<trans>/<hostname>:<port-number>
where <trans> is the transport type to use to
connect to the font server (e.g., unix for
UNIX-domain sockets or tcp for a TCP/IP connec-
tion), <hostname> is the hostname of the machine
running the font server, and <port-number> is the
port number that the font server is listening on
(usually 7100).
When this entry is not specified in the config file,
the server falls back to the compiled-in default font
path, which contains the following font path elements
(which can be set inside a catalogue directory):
/usr/share/fonts/X11/misc/
/usr/share/fonts/X11/TTF/
/usr/share/fonts/X11/OTF/
/usr/share/fonts/X11/Type1/
/usr/share/fonts/X11/100dpi/
/usr/share/fonts/X11/75dpi/
Font path elements that are found to be invalid are
removed from the font path when the server starts up.
ModulePath 34path34
sets the search path for loadable Xorg server mod-
ules. This path is a comma separated list of direc-
tories which the Xorg server searches for loadable
modules loading in the order specified. Multiple
ModulePath entries may be specified, and they will be
concatenated to build the module search path used by
the server. The default module path is
/usr/lib/xorg/modules
XkbDir 34path34
sets the base directory for keyboard layout files.
The -xkbdir command line option can be used to over-
ride this. The default directory is
/usr/share/X11/xkb
SERVERFLAGS SECTION
In addition to options specific to this section (described
below), the ServerFlags section is used to specify some glo-
bal Xorg server options. All of the entries in this section
are Options, although for compatibility purposes some of the
old style entries are still recognised. Those old style
entries are not documented here, and using them is discour-
aged. The ServerFlags section is optional, as are the
entries that may be specified in it.
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Options specified in this section (with the exception of the
34DefaultServerLayout34 Option) may be overridden by Options
specified in the active ServerLayout section. Options with
command line equivalents are overridden when their command
line equivalent is used. The options recognised by this
section are:
Option 34Debug34 34string34
This comma-separated list provides a way to control
various debugging switches from the config file. At
the moment the only defined value is dmabuf_capable
which instructs glamor to enable some unstable buffer
management code.
Option 34DefaultServerLayout34 34layout-id34
This specifies the default ServerLayout section to
use in the absence of the -layout command line
option.
Option 34NoTrapSignals34 34boolean34
This prevents the Xorg server from trapping a range
of unexpected fatal signals and exiting cleanly.
Instead, the Xorg server will die and drop core where
the fault occurred. The default behaviour is for the
Xorg server to exit cleanly, but still drop a core
file. In general you never want to use this option
unless you are debugging an Xorg server problem and
know how to deal with the consequences.
Option 34DontVTSwitch34 34boolean34
This disallows the use of the Ctrl+Alt+Fn sequence
(where Fn refers to one of the numbered function
keys). That sequence is normally used to switch to
another 34virtual terminal34 on operating systems that
have this feature. When this option is enabled, that
key sequence has no special meaning and is passed to
clients. Default: off.
Option 34DontZap34 34boolean34
This disallows the use of the Terminate_Server XKB
action (usually on Ctrl+Alt+Backspace, depending on
XKB options). This action is normally used to termi-
nate the Xorg server. When this option is enabled,
the action has no effect. Default: off.
Option 34DontZoom34 34boolean34
This disallows the use of the Ctrl+Alt+Keypad-Plus
and Ctrl+Alt+Keypad-Minus sequences. These sequences
allows you to switch between video modes. When this
option is enabled, those key sequences have no spe-
cial meaning and are passed to clients. Default:
off.
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Option 34DisableVidModeExtension34 34boolean34
This disables the parts of the VidMode extension used
by the xvidtune client that can be used to change the
video modes. Default: the VidMode extension is
enabled.
Option 34AllowNonLocalXvidtune34 34boolean34
This allows the xvidtune client (and other clients
that use the VidMode extension) to connect from
another host. Default: off.
Option 34AllowMouseOpenFail34 34boolean34
This tells the mousedrv(4) and vmmouse(4) drivers to
not report failure if the mouse device can't be
opened/initialised. It has no effect on the evdev(4)
or other drivers. Default: false.
Option 34BlankTime34 34time34
sets the inactivity timeout for the blank phase of
the screensaver. time is in minutes. This is equiv-
alent to the Xorg server's -s flag, and the value can
be changed at run-time with xset(1). Default: 10
minutes.
Option 34StandbyTime34 34time34
sets the inactivity timeout for the standby phase of
DPMS mode. time is in minutes, and the value can be
changed at run-time with xset(1). Default: 10 min-
utes. This is only suitable for VESA DPMS compatible
monitors, and may not be supported by all video
drivers. It is only enabled for screens that have
the 34DPMS34 option set (see the MONITOR section
below).
Option 34SuspendTime34 34time34
sets the inactivity timeout for the suspend phase of
DPMS mode. time is in minutes, and the value can be
changed at run-time with xset(1). Default: 10 min-
utes. This is only suitable for VESA DPMS compatible
monitors, and may not be supported by all video
drivers. It is only enabled for screens that have
the 34DPMS34 option set (see the MONITOR section
below).
Option 34OffTime34 34time34
sets the inactivity timeout for the off phase of DPMS
mode. time is in minutes, and the value can be
changed at run-time with xset(1). Default: 10 min-
utes. This is only suitable for VESA DPMS compatible
monitors, and may not be supported by all video
drivers. It is only enabled for screens that have
the 34DPMS34 option set (see the MONITOR section
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below).
Option 34MaxClients34 34integer34
Set the maximum number of clients allowed to connect
to the X server. Acceptable values are 64, 128, 256
or 512.
Option 34NoPM34 34boolean34
Disables something to do with power management
events. Default: PM enabled on platforms that sup-
port it.
Option 34Xinerama34 34boolean34
enable or disable XINERAMA extension. Default is
disabled.
Option 34IndirectGLX34 34boolean34
enable or disable indirect GLX contexts. Indirect GLX
contexts are disabled by default.
Option 34DRI234 34boolean34
enable or disable DRI2. DRI2 is disabled by default.
Option 34GlxVisuals34 34string34
This option controls how many GLX visuals the GLX
modules sets up. The default value is typical, which
will setup up a typical subset of the GLXFBConfigs
provided by the driver as GLX visuals. Other options
are minimal, which will set up the minimal set
allowed by the GLX specification and all which will
setup GLX visuals for all GLXFBConfigs.
Option 34UseDefaultFontPath34 34boolean34
Include the default font path even if other paths are
specified in xorg.conf. If enabled, other font paths
are included as well. Enabled by default.
Option 34IgnoreABI34 34boolean34
Allow modules built for a different, potentially
incompatible version of the X server to load. Dis-
abled by default.
Option 34AutoAddDevices34 34boolean34
If this option is disabled, then no devices will be
added from the HAL or udev backends. Enabled by
default.
Option 34AutoEnableDevices34 34boolean34
If this option is disabled, then the devices will be
added (and the DevicePresenceNotify event sent), but
not enabled, thus leaving policy up to the client.
Enabled by default.
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Option 34AutoAddGPU34 34boolean34
If this option is disabled, then no GPU devices will
be added from the udev backend. Enabled by default.
(May need to be disabled to setup Xinerama).
Option 34Log34 34string34
This option controls whether the log is flushed
and/or synced to disk after each message. Possible
values are flush or sync. Unset by default.
MODULE SECTION
The Module section is used to specify which Xorg server mod-
ules should be loaded. This section is ignored when the
Xorg server is built in static form. The type of modules
normally loaded in this section are Xorg server extension
modules. Most other module types are loaded automatically
when they are needed via other mechanisms. The Module sec-
tion is optional, as are all of the entries that may be
specified in it.
Entries in this section may be in two forms. The first and
most commonly used form is an entry that uses the Load key-
word, as described here:
Load 34modulename34
This instructs the server to load the module called
modulename. The module name given should be the
module's standard name, not the module file name.
The standard name is case-sensitive, and does not
include the lqlibrq or lqcygrq prefixes, or the lq.sorq or
lq.dllrq suffixes.
Example: the DRI extension module can be loaded with
the following entry:
Load 34dri34
Disable 34modulename34
This instructs the server to not load the module
called modulename. Some modules are loaded by default
in the server, and this overrides that default. If a
Load instruction is given for the same module, it
overrides the Disable instruction and the module is
loaded. The module name given should be the module's
standard name, not the module file name. As with the
Load instruction, the standard name is case-
sensitive, and does not include the "lib" prefix, or
the ".a", ".o", or ".so" suffixes.
The second form of entry is a SubSection, with the subsec-
tion name being the module name, and the contents of the
SubSection being Options that are passed to the module when
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it is loaded.
Example: the extmod module (which contains a miscellaneous
group of server extensions) can be loaded, with the
XFree86-DGA extension disabled by using the following entry:
SubSection 34extmod34
Option 34omit XFree86-DGA34
EndSubSection
Modules are searched for in each directory specified in the
ModulePath search path, and in the drivers, extensions,
input, internal, and multimedia subdirectories of each of
those directories. In addition to this, operating system
specific subdirectories of all the above are searched first
if they exist.
To see what extension modules are available, check the
extensions subdirectory under:
/usr/lib/xorg/modules
The lqextmodrq, lqdberq, lqdrirq, lqdri2rq, lqglxrq, and lqrecordrq
extension modules are loaded automatically, if they are pre-
sent, unless disabled with 34Disable34 entries. It is recom-
mended that at very least the lqextmodrq extension module be
loaded. If it isn't, some commonly used server extensions
(like the SHAPE extension) will not be available.
EXTENSIONS SECTION
The Extensions section is used to specify which X11 protocol
extensions should be enabled or disabled. The Extensions
section is optional, as are all of the entries that may be
specified in it.
Entries in this section are listed as Option statements with
the name of the extension as the first argument, and a
boolean value as the second. The extension name is
case-sensitive, and matches the form shown in the output of
34Xorg -extension ?34.
Example: the MIT-SHM extension can be disabled with
the following entry:
Section 34Extensions34
Option 34MIT-SHM34 34Disable34
EndSection
INPUTDEVICE SECTION
The config file may have multiple InputDevice sections.
Recent X servers employ HAL or udev backends for input
device enumeration and input hotplugging. It is usually not
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necessary to provide InputDevice sections in the xorg.conf
if hotplugging is in use (i.e. AutoAddDevices is enabled).
If hotplugging is enabled, InputDevice sections using the
mouse, kbd and vmmouse driver will be ignored.
If hotplugging is disabled, there will normally be at least
two: one for the core (primary) keyboard and one for the
core pointer. If either of these two is missing, a default
configuration for the missing ones will be used. In the
absence of an explicitly specified core input device, the
first InputDevice marked as CorePointer (or CoreKeyboard) is
used. If there is no match there, the first InputDevice
that uses the lqmouserq (or lqkbdrq) driver is used. The final
fallback is to use built-in default configurations. Cur-
rently the default configuration may not work as expected on
all platforms.
InputDevice sections have the following format:
Section 34InputDevice34
Identifier 34name34
Driver 34inputdriver34
options
...
EndSection
The Identifier and Driver entries are required in all
InputDevice sections. All other entries are optional.
The Identifier entry specifies the unique name for this
input device. The Driver entry specifies the name of the
driver to use for this input device. When using the load-
able server, the input driver module 34inputdriver34 will be
loaded for each active InputDevice section. An InputDevice
section is considered active if it is referenced by an
active ServerLayout section, if it is referenced by the
-keyboard or -pointer command line options, or if it is
selected implicitly as the core pointer or keyboard device
in the absence of such explicit references. The most com-
monly used input drivers are evdev(4) on Linux systems, and
kbd(4) and mousedrv(4) on other platforms.
InputDevice sections recognise some driver-independent
Options, which are described here. See the individual input
driver manual pages for a description of the device-specific
options.
Option 34AutoServerLayout34 34boolean34
Always add the device to the ServerLayout section
used by this instance of the server. This affects
implied layouts as well as explicit layouts specified
in the configuration and/or on the command line.
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Option 34CorePointer34
Deprecated, see Floating
Option 34CoreKeyboard34
Deprecated, see Floating
Option 34AlwaysCore34 34boolean34
Deprecated, see Floating
Option 34SendCoreEvents34 34boolean34
Deprecated, see Floating
Option 34Floating34 34boolean34
When enabled, the input device is set up floating and
does not report events through any master device or
control a cursor. The device is only available to
clients using the X Input Extension API. This option
is disabled by default. The options CorePointer,
CoreKeyboard, AlwaysCore, and SendCoreEvents, are the
inverse of option Floating (i.e. SendCoreEvents 34on34
is equivalent to Floating 34off34 ).
This option controls the startup behavior only, a
device may be reattached or set floating at runtime.
Specifies the 3x3 transformation matrix for absolute
input devices. The input device will be bound to the
area given in the matrix. In most configurations,
"a" and "e" specify the width and height of the area
the device is bound to, and "c" and "f" specify the x
and y offset of the area. The value range is 0 to 1,
where 1 represents the width or height of all root
windows together, 0.5 represents half the area, etc.
The values represent a 3x3 matrix, with the first,
second and third group of three values representing
the first, second and third row of the matrix,
respectively. The identity matrix is "1 0 0 0 1 0 0
0 1".
POINTER ACCELERATION
For pointing devices, the following options control how the
pointer is accelerated or decelerated with respect to physi-
cal device motion. Most of these can be adjusted at runtime,
see the xinput(1) man page for details. Only the most impor-
tant acceleration options are discussed here.
Option 34AccelerationProfile34 34integer34
Select the profile. In layman's terms, the profile
constitutes the "feeling" of the acceleration. More
formally, it defines how the transfer function
(actual acceleration as a function of current device
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velocity and acceleration controls) is constructed.
This is mainly a matter of personal preference.
0 classic (mostly compatible)
-1 none (only constant deceleration is applied)
1 device-dependent
2 polynomial (polynomial function)
3 smooth linear (soft knee, then linear)
4 simple (normal when slow, otherwise accelerated)
5 power (power function)
6 linear (more speed, more acceleration)
7 limited (like linear, but maxes out at threshold)
Option 34ConstantDeceleration34 34real34
Makes the pointer go deceleration times slower than
normal. Most useful for high-resolution devices. A
value between 0 and 1 will speed up the pointer.
Option 34AdaptiveDeceleration34 34real34
Allows to actually decelerate the pointer when going
slow. At most, it will be adaptive deceleration times
slower. Enables precise pointer placement without
sacrificing speed.
Option 34AccelerationScheme34 34string34
Selects the scheme, which is the underlying algo-
rithm.
predictable default algorithm (behaving more predictable)
lightweight old acceleration code (as specified in the X protocol spec)
none no acceleration or deceleration
Option 34AccelerationNumerator34 34integer34
Option 34AccelerationDenominator34 34integer34
Set numerator and denominator of the acceleration
factor. The acceleration factor is a rational which,
together with threshold, can be used to tweak pro-
files to suit the users needs. The simple and limited
profiles use it directly (i.e. they accelerate by the
factor), for other profiles it should hold that a
higher acceleration factor leads to a faster pointer.
Typically, 1 is unaccelerated and values up to 5 are
sensible.
Option 34AccelerationThreshold34 34integer34
Set the threshold, which is roughly the velocity
(usually device units per 10 ms) required for accel-
eration to become effective. The precise effect
varies with the profile however.
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INPUTCLASS SECTION
The config file may have multiple InputClass sections.
These sections are optional and are used to provide configu-
ration for a class of input devices as they are automati-
cally added. An input device can match more than one
InputClass section. Each class can override settings from a
previous class, so it is best to arrange the sections with
the most generic matches first.
InputClass sections have the following format:
Section 34InputClass34
Identifier 34name34
entries
...
options
...
EndSection
The Identifier entry is required in all InputClass sections.
All other entries are optional.
The Identifier entry specifies the unique name for this
input class. The Driver entry specifies the name of the
driver to use for this input device. After all classes have
been examined, the 34inputdriver34 module from the first
Driver entry will be enabled when using the loadable server.
When an input device is automatically added, its character-
istics are checked against all InputClass sections. Each
section can contain optional entries to narrow the match of
the class. If none of the optional entries appear, the
InputClass section is generic and will match any input
device. If more than one of these entries appear, they all
must match for the configuration to apply.
There are two types of match entries used in InputClass sec-
tions. The first allows various tokens to be matched against
attributes of the device. An entry can be constructed to
match attributes from different devices by separating argu-
ments with a '|' character. Multiple entries of the same
type may be supplied to add multiple matching conditions on
the same attribute. For example:
Section 34InputClass34
Identifier 34My Class34
# product string must contain example and
# either gizmo or gadget
MatchProduct 34example34
MatchProduct 34gizmo|gadget34
NoMatchDriver 34drivername34
...
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EndSection
MatchProduct 34matchproduct34
This entry can be used to check if the substring
34matchproduct34 occurs in the device's product name.
MatchVendor 34matchvendor34
This entry can be used to check if the substring
34matchvendor34 occurs in the device's vendor name.
MatchDevicePath 34matchdevice34
This entry can be used to check if the device file
matches the 34matchdevice34 pathname pattern.
MatchOS 34matchos34
This entry can be used to check if the operating sys-
tem matches the case-insensitive 34matchos34 string.
This entry is only supported on platforms providing
the uname(2) system call.
MatchPnPID 34matchpnp34
The device's Plug and Play (PnP) ID can be checked
against the 34matchpnp34 shell wildcard pattern.
MatchUSBID 34matchusb34
The device's USB ID can be checked against the
34matchusb34 shell wildcard pattern. The ID is con-
structed as lowercase hexadecimal numbers separated
by a ':'. This is the same format as the lsusb(8)
program.
MatchDriver 34matchdriver34
Check the case-sensitive string 34matchdriver34 against
the currently configured driver of the device. Order-
ing of sections using this entry is important since
it will not match unless the driver has been set by
the config backend or a previous InputClass section.
MatchTag 34matchtag34
This entry can be used to check if tags assigned by
the config backend matches the 34matchtag34 pattern. A
match is found if at least one of the tags given in
34matchtag34 matches at least one of the tags assigned
by the backend.
MatchLayout 34matchlayout34
Check the case-sensitive string 34matchlayout34 against
the currently active ServerLayout section. The empty
string "" matches an implicit layout which appears if
no named ServerLayout sections have been found.
The above directives have equivalents for negative matching
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with the NoMatchProduct, NoMatchVendor, NoMatchDevicePath,
NoMatchOS, NoMatchPnPID, NoMatchUSBID, NoMatchDriver,
NoMatchTag, and NoMatchLayout directives. These NoMatch
directives match if the subsequent match is not met by the
device.
The second type of entry is used to match device types.
These entries take a boolean argument similar to Option
entries.
MatchIsKeyboard 34bool34
MatchIsPointer 34bool34
MatchIsJoystick 34bool34
MatchIsTablet 34bool34
MatchIsTabletPad 34bool34
MatchIsTouchpad 34bool34
MatchIsTouchscreen 34bool34
When an input device has been matched to the InputClass sec-
tion, any Option entries are applied to the device. One
InputClass specific Option is recognized. See the
InputDevice section above for a description of the remaining
Option entries.
Option 34Ignore34 34boolean34
This optional entry specifies that the device should
be ignored entirely, and not added to the server.
This can be useful when the device is handled by
another program and no X events should be generated.
OUTPUTCLASS SECTION
The config file may have multiple OutputClass sections.
These sections are optional and are used to provide configu-
ration for a class of output devices as they are automati-
cally added. An output device can match more than one
OutputClass section. Each class can override settings from
a previous class, so it is best to arrange the sections with
the most generic matches first.
OutputClass sections have the following format:
Section 34OutputClass34
Identifier 34name34
entries
...
EndSection
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The Identifier entry is required in all OutputClass sec-
tions. All other entries are optional.
The Identifier entry specifies the unique name for this out-
put class. The Driver entry specifies the name of the
driver to use for this output device. After all classes
have been examined, the 34outputdriver34 module from the first
Driver entry will be enabled when using the loadable server.
When an output device is automatically added, its character-
istics are checked against all OutputClass sections. Each
section can contain optional entries to narrow the match of
the class. If none of the optional entries appear, the
OutputClass section is generic and will match any output
device. If more than one of these entries appear, they all
must match for the configuration to apply.
The following list of tokens can be matched against
attributes of the device. An entry can be constructed to
match attributes from different devices by separating argu-
ments with a '|' character.
For example:
Section 34OutputClass34
Identifier 34My Class34
# kernel driver must be either foo or bar
MatchDriver 34foo|bar34
...
EndSection
MatchDriver 34matchdriver34
Check the case-sensitive string 34matchdriver34 against
the kernel driver of the device.
When an output device has been matched to the OutputClass
section, any Option entries are applied to the device. One
OutputClass specific Option is recognized. See the Device
section below for a description of the remaining Option
entries.
Option 34PrimaryGPU34 34boolean34
This option specifies that the matched device should
be treated as the primary GPU, replacing the selec-
tion of the GPU used as output by the firmware. If
multiple output devices match an OutputClass section
with the PrimaryGPU option set, the first one enumer-
ated becomes the primary GPU.
A OutputClass Section may contain ModulePath entries. When
an output device matches an OutputClass section, any
ModulePath entries in that OutputClass are pre-pended to the
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search path for loadable Xorg server modules. See ModulePath
in the Files section for more info.
DEVICE SECTION
The config file may have multiple Device sections. There
must be at least one, for the video card being used.
Device sections have the following format:
Section 34Device34
Identifier 34name34
Driver 34driver34
entries
...
EndSection
The Identifier and Driver entries are required in all Device
sections. All other entries are optional.
The Identifier entry specifies the unique name for this
graphics device. The Driver entry specifies the name of the
driver to use for this graphics device. When using the
loadable server, the driver module 34driver34 will be loaded
for each active Device section. A Device section is consid-
ered active if it is referenced by an active Screen section.
Device sections recognise some driver-independent entries
and Options, which are described here. Not all drivers make
use of these driver-independent entries, and many of those
that do don't require them to be specified because the
information is auto-detected. See the individual graphics
driver manual pages for further information about this, and
for a description of the device-specific options. Note that
most of the Options listed here (but not the other entries)
may be specified in the Screen section instead of here in
the Device section.
BusID 34bus-id34
This specifies the bus location of the graphics card.
For PCI/AGP cards, the bus-id string has the form
PCI:bus@domain:device (e.g., lqPCI:1@0:0:0rq might be
appropriate for an AGP card). The "@domain" part can
be left out for PCI domain 0. This field is usually
optional in single-head configurations when using the
primary graphics card. In multi-head configurations,
or when using a secondary graphics card in a single-
head configuration, this entry is mandatory. Its
main purpose is to make an unambiguous connection
between the device section and the hardware it is
representing. This information can usually be found
by running the pciaccess tool scanpci.
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Screen number
This option is mandatory for cards where a single PCI
entity can drive more than one display (i.e., multi-
ple CRTCs sharing a single graphics accelerator and
video memory). One Device section is required for
each head, and this parameter determines which head
each of the Device sections applies to. The legal
values of number range from 0 to one less than the
total number of heads per entity. Most drivers
require that the primary screen (0) be present.
Chipset 34chipset34
This usually optional entry specifies the chipset
used on the graphics board. In most cases this entry
is not required because the drivers will probe the
hardware to determine the chipset type. Don't spec-
ify it unless the driver-specific documentation rec-
ommends that you do.
Ramdac 34ramdac-type34
This optional entry specifies the type of RAMDAC used
on the graphics board. This is only used by a few of
the drivers, and in most cases it is not required
because the drivers will probe the hardware to deter-
mine the RAMDAC type where possible. Don't specify
it unless the driver-specific documentation recom-
mends that you do.
DacSpeed speed
DacSpeed speed-8 speed-16 speed-24 speed-32
This optional entry specifies the RAMDAC speed rating
(which is usually printed on the RAMDAC chip). The
speed is in MHz. When one value is given, it applies
to all framebuffer pixel sizes. When multiple values
are given, they apply to the framebuffer pixel sizes
8, 16, 24 and 32 respectively. This is not used by
many drivers, and only needs to be specified when the
speed rating of the RAMDAC is different from the
defaults built in to driver, or when the driver can't
auto-detect the correct defaults. Don't specify it
unless the driver-specific documentation recommends
that you do.
Clocks clock ...
specifies the pixel that are on your graphics board.
The clocks are in MHz, and may be specified as a
floating point number. The value is stored inter-
nally to the nearest kHz. The ordering of the clocks
is important. It must match the order in which they
are selected on the graphics board. Multiple Clocks
lines may be specified, and each is concatenated to
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form the list. Most drivers do not use this entry,
and it is only required for some older boards with
non-programmable clocks. Don't specify this entry
unless the driver-specific documentation explicitly
recommends that you do.
ClockChip 34clockchip-type34
This optional entry is used to specify the clock chip
type on graphics boards which have a programmable
clock generator. Only a few Xorg drivers support
programmable clock chips. For details, see the
appropriate driver manual page.
VideoRam mem
This optional entry specifies the amount of video ram
that is installed on the graphics board. This is
measured in kBytes. In most cases this is not
required because the Xorg server probes the graphics
board to determine this quantity. The driver-
specific documentation should indicate when it might
be needed.
MemBase baseaddress
This optional entry specifies the memory base address
of a graphics board's linear frame buffer. This
entry is not used by many drivers, and it should only
be specified if the driver-specific documentation
recommends it.
IOBase baseaddress
This optional entry specifies the IO base address.
This entry is not used by many drivers, and it should
only be specified if the driver-specific documenta-
tion recommends it.
ChipID id
This optional entry specifies a numerical ID repre-
senting the chip type. For PCI cards, it is usually
the device ID. This can be used to override the
auto-detection, but that should only be done when the
driver-specific documentation recommends it.
ChipRev rev
This optional entry specifies the chip revision num-
ber. This can be used to override the auto-
detection, but that should only be done when the
driver-specific documentation recommends it.
MatchSeat seat-id
Only apply this Device section if X server was
started with -seat seat-id option.
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Option 34ModeDebug34 34boolean34
Enable printing of additional debugging information
about modesetting to the server log.
Option 34PreferCloneMode34 34boolean34
If enabled, bring up monitors of a screen in clone
mode instead of horizontal extended layout by
default. (Defaults to off; the video driver can
change the default value, but this option can always
override it)
Options
Option flags may be specified in the Device sections.
These include driver-specific options and
driver-independent options. The former are described
in the driver-specific documentation. Some of the
latter are described below in the section about the
Screen section, and they may also be included here.
VIDEOADAPTOR SECTION
Nobody wants to say how this works. Maybe nobody knows ...
MONITOR SECTION
The config file may have multiple Monitor sections. There
should normally be at least one, for the monitor being used,
but a default configuration will be created when one isn't
specified.
Monitor sections have the following format:
Section 34Monitor34
Identifier 34name34
entries
...
EndSection
The only mandatory entry in a Monitor section is the
Identifier entry.
The Identifier entry specifies the unique name for this mon-
itor. The Monitor section may be used to provide informa-
tion about the specifications of the monitor, monitor-
specific Options, and information about the video modes to
use with the monitor.
With RandR 1.2-enabled drivers, monitor sections may be tied
to specific outputs of the video card. Using the name of
the output defined by the video driver plus the identifier
of a monitor section, one associates a monitor section with
an output by adding an option to the Device section in the
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following format:
Option 34Monitor-outputname34 34monitorsection34
(for example, Option 34Monitor-VGA34 34VGA monitor34 for a VGA
output)
In the absence of specific association of monitor sections
to outputs, if a monitor section is present the server will
associate it with an output to preserve compatibility for
previous single-head configurations.
Specifying video modes is optional because the server will
use the DDC or other information provided by the monitor to
automatically configure the list of modes available. When
modes are specified explicitly in the Monitor section (with
the Mode, ModeLine, or UseModes keywords), built-in modes
with the same names are not included. Built-in modes with
different names are, however, still implicitly included,
when they meet the requirements of the monitor.
The entries that may be used in Monitor sections are
described below.
VendorName 34vendor34
This optional entry specifies the monitor's manufac-
turer.
ModelName 34model34
This optional entry specifies the monitor's model.
HorizSync horizsync-range
gives the range(s) of horizontal sync frequencies
supported by the monitor. horizsync-range may be a
comma separated list of either discrete values or
ranges of values. A range of values is two values
separated by a dash. By default the values are in
units of kHz. They may be specified in MHz or Hz if
MHz or Hz is added to the end of the line. The data
given here is used by the Xorg server to determine if
video modes are within the specifications of the mon-
itor. This information should be available in the
monitor's handbook. If this entry is omitted, a
default range of 28-33kHz is used.
VertRefresh vertrefresh-range
gives the range(s) of vertical refresh frequencies
supported by the monitor. vertrefresh-range may be a
comma separated list of either discrete values or
ranges of values. A range of values is two values
separated by a dash. By default the values are in
units of Hz. They may be specified in MHz or kHz if
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MHz or kHz is added to the end of the line. The data
given here is used by the Xorg server to determine if
video modes are within the specifications of the mon-
itor. This information should be available in the
monitor's handbook. If this entry is omitted, a
default range of 43-72Hz is used.
DisplaySize width height
This optional entry gives the width and height, in
millimetres, of the picture area of the monitor. If
given this is used to calculate the horizontal and
vertical pitch (DPI) of the screen.
Gamma gamma-value
Gamma red-gamma green-gamma blue-gamma
This is an optional entry that can be used to specify
the gamma correction for the monitor. It may be
specified as either a single value or as three sepa-
rate RGB values. The values should be in the range
0.1 to 10.0, and the default is 1.0. Not all drivers
are capable of using this information.
UseModes 34modesection-id34
Include the set of modes listed in the Modes section
called modesection-id. This makes all of the modes
defined in that section available for use by this
monitor.
Mode 34name34
This is an optional multi-line entry that can be used
to provide definitions for video modes for the moni-
tor. In most cases this isn't necessary because the
built-in set of VESA standard modes will be suffi-
cient. The Mode keyword indicates the start of a
multi-line video mode description. The mode descrip-
tion is terminated with the EndMode keyword. The
mode description consists of the following entries:
DotClock clock
is the dot (pixel) clock rate to be used for the
mode.
HTimings hdisp hsyncstart hsyncend htotal
specifies the horizontal timings for the mode.
VTimings vdisp vsyncstart vsyncend vtotal
specifies the vertical timings for the mode.
Flags 34flag34 ...
specifies an optional set of mode flags, each of
which is a separate string in double quotes.
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34Interlace34 indicates that the mode is inter-
laced. 34DoubleScan34 indicates a mode where each
scanline is doubled. 34+HSync34 and 34-HSync34 can
be used to select the polarity of the HSync sig-
nal. 34+VSync34 and 34-VSync34 can be used to select
the polarity of the VSync signal. 34Composite34
can be used to specify composite sync on hardware
where this is supported. Additionally, on some
hardware, 34+CSync34 and 34-CSync34 may be used to
select the composite sync polarity.
HSkew hskew
specifies the number of pixels (towards the right
edge of the screen) by which the display enable
signal is to be skewed. Not all drivers use this
information. This option might become necessary
to override the default value supplied by the
server (if any). lqRovingrq horizontal lines indi-
cate this value needs to be increased. If the
last few pixels on a scan line appear on the left
of the screen, this value should be decreased.
VScan vscan
specifies the number of times each scanline is
painted on the screen. Not all drivers use this
information. Values less than 1 are treated as
1, which is the default. Generally, the
34DoubleScan34 Flag mentioned above doubles this
value.
ModeLine 34name34 mode-description
This entry is a more compact version of the Mode
entry, and it also can be used to specify video modes
for the monitor. This is a single line format for
specifying video modes. In most cases this isn't
necessary because the built-in set of VESA standard
modes will be sufficient.
The mode-description is in four sections, the first
three of which are mandatory. The first is the dot
(pixel) clock. This is a single number specifying
the pixel clock rate for the mode in MHz. The second
section is a list of four numbers specifying the hor-
izontal timings. These numbers are the hdisp,
hsyncstart, hsyncend, and htotal values. The third
section is a list of four numbers specifying the ver-
tical timings. These numbers are the vdisp,
vsyncstart, vsyncend, and vtotal values. The final
section is a list of flags specifying other charac-
teristics of the mode. Interlace indicates that the
mode is interlaced. DoubleScan indicates a mode
where each scanline is doubled. +HSync and -HSync
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can be used to select the polarity of the HSync sig-
nal. +VSync and -VSync can be used to select the
polarity of the VSync signal. Composite can be used
to specify composite sync on hardware where this is
supported. Additionally, on some hardware, +CSync
and -CSync may be used to select the composite sync
polarity. The HSkew and VScan options mentioned
above in the Mode entry description can also be used
here.
Option 34DPMS34 34bool34
This option controls whether the server should enable
the DPMS extension for power management for this
screen. The default is to enable the extension.
Option 34SyncOnGreen34 34bool34
This option controls whether the video card should
drive the sync signal on the green color pin. Not
all cards support this option, and most monitors do
not require it. The default is off.
Option 34Primary34 34bool34
This optional entry specifies that the monitor should
be treated as the primary monitor. (RandR 1.2-
supporting drivers only)
Option 34PreferredMode34 34name34
This optional entry specifies a mode to be marked as
the preferred initial mode of the monitor. (RandR
1.2-supporting drivers only)
Option 34ZoomModes34 34name name ...
This optional entry specifies modes to be marked as
zoom modes. It is possible to switch to the next and
previous mode via Ctrl+Alt+Keypad-Plus and
Ctrl+Alt+Keypad-Minus. All these keypad available
modes are selected from the screen mode list. This
list is a copy of the compatibility output monitor
mode list. Since this output is the output connected
to the lowest dot-area monitor, as determined from
its largest size mode, that monitor defines the
available zoom modes. (RandR 1.2-supporting drivers
only)
Option 34Position34 34x y34
This optional entry specifies the position of the
monitor within the X screen. (RandR 1.2-supporting
drivers only)
Option 34LeftOf34 34output34
This optional entry specifies that the monitor should
be positioned to the left of the output (not monitor)
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of the given name. (RandR 1.2-supporting drivers
only)
Option 34RightOf34 34output34
This optional entry specifies that the monitor should
be positioned to the right of the output (not moni-
tor) of the given name. (RandR 1.2-supporting
drivers only)
Option 34Above34 34output34
This optional entry specifies that the monitor should
be positioned above the output (not monitor) of the
given name. (RandR 1.2-supporting drivers only)
Option 34Below34 34output34
This optional entry specifies that the monitor should
be positioned below the output (not monitor) of the
given name. (RandR 1.2-supporting drivers only)
Option 34Enable34 34bool34
This optional entry specifies whether the monitor
should be turned on at startup. By default, the
server will attempt to enable all connected monitors.
(RandR 1.2-supporting drivers only)
Option 34DefaultModes34 34bool34
This optional entry specifies whether the server
should add supported default modes to the list of
modes offered on this monitor. By default, the server
will add default modes; you should only disable this
if you can guarantee that EDID will be available at
all times, or if you have added custom modelines
which the server can use. (RandR 1.2-supporting
drivers only)
Option 34MinClock34 34frequency34
This optional entry specifies the minimum dot clock,
in kHz, that is supported by the monitor.
Option 34MaxClock34 34frequency34
This optional entry specifies the maximum dot clock,
in kHz, that is supported by the monitor.
Option 34Ignore34 34bool34
This optional entry specifies that the monitor should
be ignored entirely, and not reported through RandR.
This is useful if the hardware reports the presence
of outputs that don't exist. (RandR 1.2-supporting
drivers only)
Option 34Rotate34 34rotation34
This optional entry specifies the initial rotation of
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the given monitor. Valid values for rotation are
34normal34, 34left34, 34right34, and 34inverted34. (RandR
1.2-supporting drivers only)
MODES SECTION
The config file may have multiple Modes sections, or none.
These sections provide a way of defining sets of video modes
independently of the Monitor sections. Monitor sections may
include the definitions provided in these sections by using
the UseModes keyword. In most cases the Modes sections are
not necessary because the built-in set of VESA standard
modes will be sufficient.
Modes sections have the following format:
Section 34Modes34
Identifier 34name34
entries
...
EndSection
The Identifier entry specifies the unique name for this set
of mode descriptions. The other entries permitted in Modes
sections are the Mode and ModeLine entries that are
described above in the Monitor section.
SCREEN SECTION
The config file may have multiple Screen sections. There
must be at least one, for the lqscreenrq being used. A
lqscreenrq represents the binding of a graphics device (Device
section) and a monitor (Monitor section). A Screen section
is considered lqactiverq if it is referenced by an active
ServerLayout section or by the -screen command line option.
If neither of those is present, the first Screen section
found in the config file is considered the active one.
Screen sections have the following format:
Section 34Screen34
Identifier 34name34
Device 34devid34
GPUDevice 34devid34
Monitor 34monid34
entries
...
SubSection 34Display34
entries
...
EndSubSection
...
EndSection
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The Identifier entry is mandatory. All others are optional.
The Identifier entry specifies the unique name for this
screen. The Screen section provides information specific to
the whole screen, including screen-specific Options. In
multi-head configurations, there will be multiple active
Screen sections, one for each head. The entries available
for this section are:
Device 34device-id34
This entry specifies the Device section to be used
for this screen. When multiple graphics cards are
present, this is what ties a specific card to a
screen. The device-id must match the Identifier of a
Device section in the config file.
GPUDevice 34device-id34
This entry specifies the Device section to be used as
a secondary GPU device for this screen. When multi-
ple graphics cards are present, this is what ties a
specific secondary card to a screen. The device-id
must match the Identifier of a Device section in the
config file. This can be specified up to 4 times for
a single screen.
Monitor 34monitor-id34
specifies which monitor description is to be used for
this screen. If a Monitor name is not specified, a
default configuration is used. Currently the default
configuration may not function as expected on all
platforms.
VideoAdaptor 34xv-id34
specifies an optional Xv video adaptor description to
be used with this screen.
DefaultDepth depth
specifies which color depth the server should use by
default. The -depth command line option can be used
to override this. If neither is specified, the
default depth is driver-specific, but in most cases
is 8.
DefaultFbBpp bpp
specifies which framebuffer layout to use by default.
The -fbbpp command line option can be used to over-
ride this. In most cases the driver will chose the
best default value for this. The only case where
there is even a choice in this value is for depth 24,
where some hardware supports both a packed 24 bit
framebuffer layout and a sparse 32 bit framebuffer
layout.
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MatchSeat seat-id
Only apply this Screen section if X server was
started with -seat seat-id option.
Options
Various Option flags may be specified in the Screen
section. Some are driver-specific and are described
in the driver documentation. Others are
driver-independent, and will eventually be described
here.
Option 34Accel34
Enables 2D hardware acceleration. This option is on
by default, but it may be necessary to turn it off if
there are bugs in the driver. There are many options
to disable specific accelerated operations, listed
below. Note that disabling an operation will have no
effect if the operation is not accelerated (whether
due to lack of support in the hardware or in the
driver).
Option 34GlxVendorLibrary34 34string34
This option specifies a space-separated list of
OpenGL vendor libraries to use for the screen. This
may be used to select an alternate implementation for
development, debugging, or alternate feature sets.
Default: mesa.
Option 34InitPrimary34 34boolean34
Use the Int10 module to initialize the primary graph-
ics card. Normally, only secondary cards are soft-
booted using the Int10 module, as the primary card
has already been initialized by the BIOS at boot
time. Default: false.
Option 34NoInt1034 34boolean34
Disables the Int10 module, a module that uses the
int10 call to the BIOS of the graphics card to ini-
tialize it. Default: false.
Each Screen section may optionally contain one or more
Display subsections. Those subsections provide depth/fbbpp
specific configuration information, and the one chosen
depends on the depth and/or fbbpp that is being used for the
screen. The Display subsection format is described in the
section below.
DISPLAY SUBSECTION
Each Screen section may have multiple Display subsections.
The lqactiverq Display subsection is the first that matches
the depth and/or fbbpp values being used, or failing that,
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the first that has neither a depth or fbbpp value specified.
The Display subsections are optional. When there isn't one
that matches the depth and/or fbbpp values being used, all
the parameters that can be specified here fall back to their
defaults.
Display subsections have the following format:
SubSection 34Display34
Depth depth
entries
...
EndSubSection
Depth depth
This entry specifies what colour depth the Display
subsection is to be used for. This entry is usually
specified, but it may be omitted to create a
match-all Display subsection or when wishing to match
only against the FbBpp parameter. The range of depth
values that are allowed depends on the driver. Most
drivers support 8, 15, 16 and 24. Some also support
1 and/or 4, and some may support other values (like
30). Note: depth means the number of bits in a pixel
that are actually used to determine the pixel colour.
32 is not a valid depth value. Most hardware that
uses 32 bits per pixel only uses 24 of them to hold
the colour information, which means that the colour
depth is 24, not 32.
FbBpp bpp
This entry specifies the framebuffer format this
Display subsection is to be used for. This entry is
only needed when providing depth 24 configurations
that allow a choice between a 24 bpp packed frame-
buffer format and a 32bpp sparse framebuffer format.
In most cases this entry should not be used.
Weight red-weight green-weight blue-weight
This optional entry specifies the relative RGB
weighting to be used for a screen is being used at
depth 16 for drivers that allow multiple formats.
This may also be specified from the command line with
the -weight option (see Xorg(1)).
Virtual xdim ydim
This optional entry specifies the virtual screen res-
olution to be used. xdim must be a multiple of
either 8 or 16 for most drivers, and a multiple of 32
when running in monochrome mode. The given value
will be rounded down if this is not the case. Video
modes which are too large for the specified virtual
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size will be rejected. If this entry is not present,
the virtual screen resolution will be set to accommo-
date all the valid video modes given in the Modes
entry. Some drivers/hardware combinations do not
support virtual screens. Refer to the appropriate
driver-specific documentation for details.
ViewPort x0 y0
This optional entry sets the upper left corner of the
initial display. This is only relevant when the vir-
tual screen resolution is different from the resolu-
tion of the initial video mode. If this entry is not
given, then the initial display will be centered in
the virtual display area.
Modes 34mode-name34 ...
This optional entry specifies the list of video modes
to use. Each mode-name specified must be in double
quotes. They must correspond to those specified or
referenced in the appropriate Monitor section
(including implicitly referenced built-in VESA stan-
dard modes). The server will delete modes from this
list which don't satisfy various requirements. The
first valid mode in this list will be the default
display mode for startup. The list of valid modes is
converted internally into a circular list. It is
possible to switch to the next mode with
Ctrl+Alt+Keypad-Plus and to the previous mode with
Ctrl+Alt+Keypad-Minus. When this entry is omitted,
the valid modes referenced by the appropriate Monitor
section will be used. If the Monitor section con-
tains no modes, then the selection will be taken from
the built-in VESA standard modes.
Visual 34visual-name34
This optional entry sets the default root visual
type. This may also be specified from the command
line (see the Xserver(1) man page). The visual types
available for depth 8 are (default is PseudoColor):
StaticGray
GrayScale
StaticColor
PseudoColor
TrueColor
DirectColor
The visual type available for the depths 15, 16 and
24 are (default is TrueColor):
TrueColor
DirectColor
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Not all drivers support DirectColor at these depths.
The visual types available for the depth 4 are
(default is StaticColor):
StaticGray
GrayScale
StaticColor
PseudoColor
The visual type available for the depth 1 (mono-
chrome) is StaticGray.
Black red green blue
This optional entry allows the lqblackrq colour to be
specified. This is only supported at depth 1. The
default is black.
White red green blue
This optional entry allows the lqwhiterq colour to be
specified. This is only supported at depth 1. The
default is white.
Options
Option flags may be specified in the Display subsec-
tions. These may include driver-specific options and
driver-independent options. The former are described
in the driver-specific documentation. Some of the
latter are described above in the section about the
Screen section, and they may also be included here.
SERVERLAYOUT SECTION
The config file may have multiple ServerLayout sections. A
lqserver layoutrq represents the binding of one or more
screens (Screen sections) and one or more input devices
(InputDevice sections) to form a complete configuration. In
multi-head configurations, it also specifies the relative
layout of the heads. A ServerLayout section is considered
lqactiverq if it is referenced by the -layout command line
option or by an Option 34DefaultServerLayout34 entry in the
ServerFlags section (the former takes precedence over the
latter). If those options are not used, the first
ServerLayout section found in the config file is considered
the active one. If no ServerLayout sections are present,
the single active screen and two active (core) input devices
are selected as described in the relevant sections above.
ServerLayout sections have the following format:
Section 34ServerLayout34
Identifier 34name34
Screen 34screen-id34
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...
InputDevice 34idev-id34
...
options
...
EndSection
Each ServerLayout section must have an Identifier entry and
at least one Screen entry.
The Identifier entry specifies the unique name for this
server layout. The ServerLayout section provides informa-
tion specific to the whole session, including
session-specific Options. The ServerFlags options
(described above) may be specified here, and ones given here
override those given in the ServerFlags section.
The entries that may be used in this section are described
here.
Screen screen-num 34screen-id34 position-information
One of these entries must be given for each screen
being used in a session. The screen-id field is
mandatory, and specifies the Screen section being
referenced. The screen-num field is optional, and
may be used to specify the screen number in
multi-head configurations. When this field is omit-
ted, the screens will be numbered in the order that
they are listed in. The numbering starts from 0, and
must be consecutive. The position-information field
describes the way multiple screens are positioned.
There are a number of different ways that this infor-
mation can be provided:
x y
Absolute x y
These both specify that the upper left corner's
coordinates are (x,y). The Absolute keyword is
optional. Some older versions of XFree86 (4.2
and earlier) don't recognise the Absolute key-
word, so it's safest to just specify the coordi-
nates without it.
RightOf 34screen-id34
LeftOf 34screen-id34
Above 34screen-id34
Below 34screen-id34
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Relative 34screen-id34 x y
These give the screen's location relative to
another screen. The first four position the
screen immediately to the right, left, above or
below the other screen. When positioning to the
right or left, the top edges are aligned. When
positioning above or below, the left edges are
aligned. The Relative form specifies the offset
of the screen's origin (upper left corner) rela-
tive to the origin of another screen.
InputDevice 34idev-id34 34option34 ...
One of these entries should be given for each input
device being used in a session. Normally at least
two are required, one each for the core pointer and
keyboard devices. If either of those is missing,
suitable InputDevice entries are searched for using
the method described above in the INPUTDEVICE sec-
tion. The idev-id field is mandatory, and specifies
the name of the InputDevice section being referenced.
Multiple option fields may be specified, each in dou-
ble quotes. The options permitted here are any that
may also be given in the InputDevice sections. Nor-
mally only session-specific input device options
would be used here. The most commonly used options
are:
34CorePointer34
34CoreKeyboard34
34SendCoreEvents34
and the first two should normally be used to indicate
the core pointer and core keyboard devices respec-
tively.
MatchSeat seat-id
Only apply this ServerLayout section if X server was
started with -seat seat-id option.
Options
In addition to the following, any option permitted in
the ServerFlags section may also be specified here.
When the same option appears in both places, the
value given here overrides the one given in the
ServerFlags section.
Option 34IsolateDevice34 34bus-id34
Restrict device resets to the specified bus-id. See
the BusID option (described in DEVICE SECTION, above)
for the format of the bus-id parameter. This option
overrides SingleCard, if specified. At present, only
PCI devices can be isolated in this manner.
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Option 34SingleCard34 34boolean34
As IsolateDevice, except that the bus ID of the first
device in the layout is used.
Here is an example of a ServerLayout section for a dual
headed configuration with two mice:
Section 34ServerLayout34
Identifier 34Layout 134
Screen 34MGA 134
Screen 34MGA 234 RightOf 34MGA 134
InputDevice 34Keyboard 134 34CoreKeyboard34
InputDevice 34Mouse 134 34CorePointer34
InputDevice 34Mouse 234 34SendCoreEvents34
Option 34BlankTime34 34534
EndSection
DRI SECTION
This optional section is used to provide some information
for the Direct Rendering Infrastructure. Details about the
format of this section can be found on-line at
<https://dri.freedesktop.org/>.
VENDOR SECTION
The optional Vendor section may be used to provide
vendor-specific configuration information. Multiple Vendor
sections may be present, and they may contain an Identifier
entry and multiple Option flags. The data therein is not
used in this release.
SEE ALSO
General: X(7), Xserver(1), Xorg(1), cvt(1), gtf(1).
Not all modules or interfaces are available on all
platforms.
Display drivers: apm(4), ati(4), chips(4), cirrus(4),
cyrix(4), fbdev(4), glide(4), glint(4), i128(4), i740(4),
imstt(4), intel(4), mga(4), neomagic(4), nv(4),
openchrome(4), r128(4), radeon(4), rendition(4), savage(4),
s3virge(4), siliconmotion(4), sis(4), sisusb(4), sunbw2(4),
suncg14(4), suncg3(4), suncg6(4), sunffb(4), sunleo(4),
suntcx(4), tdfx(4), trident(4), tseng(4), vesa(4),
vmware(4), voodoo(4), wsfb(4), xgi(4), xgixp(4).
Input drivers: acecad(4), citron(4), elographics(4),
evdev(4), fpit(4), joystick(4), kbd(4), libinput(4),
mousedrv(4), mutouch(4), penmount(4), synaptics(4),
vmmouse(4), void(4), wacom(4).
Other modules and interfaces: exa(4), fbdevhw(4), v4l(4).
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AUTHORS
This manual page was largely rewritten by David Dawes
<dawes@xfree86.org>.
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