Xorg/Keyboard configuration

Related articles

• X keyboard extension
• Keyboard configuration in console
• Extra keyboard keys
• Xorg
• Keyboard shortcuts

This article describes the basics of Xorg keyboard configuration. For advanced topics such as keyboard layout modification or additional key mappings, see X keyboard extension or Extra keyboard keys respectively.

The Xorg server uses the X keyboard extension (XKB) to define keyboard layouts. Optionally, xmodmap can be used to access the internal keymap table directly, although this is not recommended for complex tasks. Also systemd's localectl can be used to define the keyboard layout for both the Xorg server and the virtual console.

Note: XKB options can be overridden by the tools provided by some desktop environments such as GNOME and KDE.

Viewing keyboard settings

You can use the following command to see the actual XKB settings:

$ setxkbmap -print -verbose 10

Setting verbose level to 10
locale is C
Applied rules from evdev:
model:      evdev
layout:     us
options:    terminate:ctrl_alt_bksp
Trying to build keymap using the following components:
keycodes:   evdev+aliases(qwerty)
types:      complete
compat:     complete
symbols:    pc+us+inet(evdev)+terminate(ctrl_alt_bksp)
geometry:   pc(pc104)
xkb_keymap {
        xkb_keycodes  { include "evdev+aliases(qwerty)" };
        xkb_types     { include "complete"      };
        xkb_compat    { include "complete"      };
        xkb_symbols   { include "pc+us+inet(evdev)+terminate(ctrl_alt_bksp)"    };
        xkb_geometry  { include "pc(pc104)"     };
};

Third party utilities

There are some "unofficial" utilities which allow to print specific information about the currently used keyboard layout.

• xkb-switch-git^AUR:

$ xkb-switch

us

• xkblayout-state^{AUR[broken link: package not found]}:

$ xkblayout-state print "%s"

de

Setting keyboard layout

Keyboard layout in Xorg can be set in multiple ways. Here is an explanation of used options:

• XkbModel selects the keyboard model. This has an influence only for some extra keys your keyboard might have. The safe fallback are pc104 or pc105. But for instance laptops usually have some extra keys, and sometimes you can make them work by simply setting a proper model.
• XkbLayout selects the keyboard layout. Multiple layouts may be specified in a comma-separated list, e.g. if you want to quickly switch between layouts.
• XkbVariant selects a specific layout variant. For instance, the default sk variant is qwertz, but you can manually specify qwerty, etc.
• XkbOptions contains some extra options. Used for specifying layout switching, notification LED, compose mode etc. See the #Frequently used XKB options section for examples.

Note: You must specify as many variants as the number of specified layouts. If you want the default variant, specify an empty string as the variant (the comma must stay). For example, to have the default us layout as primary and the dvorak variant of us layout as secondary, specify us,us as XkbLayout and ,dvorak as XkbVariant.

The layout name is usually a 2-letter country code. To see a full list of keyboard models, layouts, variants and options, along with a short description, open /usr/share/X11/xkb/rules/base.lst. Alternatively, you may use one of the following commands to see a list without a description:

• localectl list-x11-keymap-models
• localectl list-x11-keymap-layouts
• localectl list-x11-keymap-variants [layout]
• localectl list-x11-keymap-options

Examples in the following subsections will have the same effect, they will set pc104 model, cz as primary layout, us as secondary layout, dvorak variant for us layout and the Alt+Shift combination for switching between layouts. See xkeyboard-config(7) for more detailed information.

Using setxkbmap

setxkbmap sets the keyboard layout for the current X session only, but can be made persistent in xinitrc or xprofile. This overrides system-wide configuration specified following #Using X configuration files.

The usage is as follows (see setxkbmap(1)):

$ setxkbmap [-model xkb_model] [-layout xkb_layout] [-variant xkb_variant] [-option xkb_options]

To change just the layout (-layout is the default flag):

$ setxkbmap xkb_layout

For multiple customizations:

$ setxkbmap -model pc104 -layout cz,us -variant ,dvorak -option grp:alt_shift_toggle

Using X configuration files

Note: xorg.conf is parsed by the X server at start-up. To apply changes, restart X.

The syntax of X configuration files is explained in Xorg#Configuration. This method creates system-wide configuration which is persistent across reboots.

Here is an example:

/etc/X11/xorg.conf.d/00-keyboard.conf

Section "InputClass"
        Identifier "system-keyboard"
        MatchIsKeyboard "on"
        Option "XkbLayout" "cz,us"
        Option "XkbModel" "pc104"
        Option "XkbVariant" ",dvorak"
        Option "XkbOptions" "grp:alt_shift_toggle"
EndSection

Using localectl

For convenience, the tool localectl may be used instead of manually editing X configuration files. It will save the configuration in /etc/X11/xorg.conf.d/00-keyboard.conf, this file should not be manually edited, because localectl will overwrite the changes on next start.

The usage is as follows:

$ localectl [--no-convert] set-x11-keymap layout [model [variant [options]]]

To set a model, variant or options, all preceding fields need to be specified, but the preceding fields can be skipped by passing an empty string with "". Unless the --no-convert option is passed, the specified keymap is also converted to the closest matching console keymap and applied to the console configuration in vconsole.conf. See localectl(1) for more information.

To create a /etc/X11/xorg.conf.d/00-keyboard.conf like the above:

$ localectl --no-convert set-x11-keymap cz,us pc104 ,dvorak grp:alt_shift_toggle

Frequently used XKB options

Switching between keyboard layouts

To be able to easily switch keyboard layouts, first specify multiple layouts between which you want to switch (the first one is the default). Then specify a key (or key combination), which will be used for switching. For example, to switch between a US and a Swedish layout using the CapsLock key, use us,se as an argument of XkbLayout and grp:caps_toggle as an argument of XkbOptions.

You can use other key combinations than CapsLock, they are listed in /usr/share/X11/xkb/rules/base.lst, start with grp: and end with toggle. To get the full list of available options, run the following command:

$ grep "grp:.*toggle" /usr/share/X11/xkb/rules/base.lst

Terminating Xorg with Ctrl+Alt+Backspace

By default, the key combination Ctrl+Alt+Backspace is disabled. You can enable it by passing terminate:ctrl_alt_bksp to XkbOptions. This can also be done by binding a key to Terminate_Server in xmodmap (which undoes any existing XkbOptions setting). In order for either method to work, one also needs to have DontZap set to "off" in ServerFlags; however, from at least version R6.8.0 (year 2004) [1] this is the default.

Swapping Caps Lock with Left Control

To swap Caps Lock with Left Control key, add ctrl:swapcaps to XkbOptions. Run the following command to see similar options along with their descriptions:

$ grep -E "(ctrl|caps):" /usr/share/X11/xkb/rules/base.lst

Enabling mouse keys

Mouse keys is disabled by default and has to be manually enabled by passing keypad:pointerkeys to XkbOptions. This will make the Shift+NumLock shortcut toggle mouse keys.

See also X keyboard extension#Mouse control for advanced configuration.

Configuring compose key

Though typically not on traditional keyboards, a Compose key can be configured to an existent key.

The Compose key begins a keypress sequence that involves (usually two) additional keypresses. Usage is typically either for entering characters in a language that the keyboard was not designed for, or for other less-used characters that are not covered with the AltGr modifier. For example, pressing Compose ' e produces é, or Compose - - will produce an "em dash": —.

Though a few more eccentric keyboards feature a Compose key, its availability is usually through substituting an already existing key to it. For example, to make the Menu key a Compose key use the Desktop environment configuration, or pass compose:menu to XkbOptions (or setxkbmap: setxkbmap -option compose:menu). Allowed key substitutions are defined in /usr/share/X11/xkb/rules/base.lst:

$ grep "compose:" /usr/share/X11/xkb/rules/base.lst

If the desired mapping is not found in that file, an alternative is to use xmodmap to map the desired key to the Multi_key keysym, which acts as a compose key by default (note that xmodmap settings are reset by setxkbmap).

Key combinations

The default combinations for the compose keys depend on the locale configured for the session and are stored in /usr/share/X11/locale/used_locale/Compose, where used_locale is for example en_US.UTF-8.

You can define your own compose key combinations by copying the default file to ~/.XCompose and editing it. The compose key works with any of the thousands of valid Unicode characters, including those outside the Basic Multilingual Plane. Take a look at the Compose(5) man page, it explains the format of the XCompose files.

However, GTK does not use XIM by default and therefore does not follow ~/.XCompose keys. This can be fixed by forcing GTK to use XIM by adding export GTK_IM_MODULE=xim and/or export XMODIFIERS="@im=none" to ~/.xprofile.

Tip: XIM is very old, you might have better luck with other input methods: SCIM, UIM, IBus, etc. See Localization#Input methods for details.

Note: XIM will prevent insertion of Unicode characters with the Ctrl+Shift+u combination.

Currency sign on other key

Most European keyboards have a Euro sign (€) printed on on the 5 key. For example, to access it with Alt+5, use the lv3:lalt_switch and eurosign:5 options.

The Rupee sign (₹) can be used the same way with rupeesign:4.

Switching state immediately when Caps Lock is pressed

Those who prefer typing capital letters with the Caps Lock key may experience a short delay when Caps Lock state is switched, resulting in two or more capital letters (e.g. THe, ARch LInux). This behaviour stems from typewriters.

Some more popular operating systems have removed this behaviour, either voluntarily (as it can be confusing to some) or by mistake, however this is a question of preference. Bug reports have been filed on the Xserver bug tracker, as there is currently no easy way to switch to the behaviour reflected by those other operating systems. For anyone who would like to follow up the issue, bug reports and latest working progress can be found at [2] and [3].

Workaround

First, export your keyboard configurations to a file:

$ xkbcomp -xkb $DISPLAY xkbmap

In the file xkbmap, locate the Caps Lock section which begins with key <CAPS>:

 key <CAPS> {         [       Caps_Lock ] };

and replace whole section with the following code:

key <CAPS> {
    repeat=no,
    type[group1]="ALPHABETIC",
    symbols[group1]=[ Caps_Lock, Caps_Lock],
    actions[group1]=[ LockMods(modifiers=Lock), Private(type=3,data[0]=1,data[1]=3,data[2]=3)]
};

Save and reload keyboard configurations:

$ xkbcomp -w 0 xkbmap $DISPLAY

Consider making it a service launching after X starts, since reloaded configurations do not survive a system reboot.

Adjusting typematic delay and rate

The typematic delay indicates the amount of time (typically in miliseconds) a key needs to be pressed and held in order for the repeating process to begin. After the repeating process has been triggered, the character will be repeated with a certain frequency (usually given in Hz) specified by the typematic rate. Note that these settings are configured seperately for Xorg and for the virtual console.

Using xset

The tool xset can be used to set the typematic delay and rate for an active X server, certain actions during runtime tho may cause the XServer to reset these changes and revert instead to its seat defaults.

Usage:

$ xset r rate delay [rate]

For example to set a typematic delay to 200ms and a typematic rate to 30Hz, use the following command (use xinitrc to make it permanent):

$ xset r rate 200 30

Issuing the command without specifying the delay and rate will reset the typematic values to their respective defaults; a delay of 660ms and a rate of 25Hz:

$ xset r rate

Using XServer startup options

A more resistant way to set the typematic delay and rate is to make them the seat defaults by passing the desired settings to the X server on its startup using the following options:

• -ardelay miliseconds - sets the autorepeat delay (length of time in milliseconds that a key must be depressed before autorepeat starts).
• -arinterval miliseconds - sets the autorepeat interval (length of time in milliseconds that should elapse between autorepeat-generated keystrokes).

See Xserver(1) for a full list of X server options and refer to your display manager for information about how to pass these options.

Keybinding

When we are in a graphical environment we may want to execute a command when certain key combination is pressed (i.e. bind a command to a keysym). There are multiple ways to do that:

• The most portable way using low level tools, such as acpid. Not all keys are supported, but configuration in uniform way is possible for keyboard keys, power adapter connection and even headphone jack (un)plugging events. It is also difficult to run programs inside X session correctly.
• The universal way using Xorg utilities (e.g. xbindkeys) and eventually your desktop environment or window manager tools.
• The quicker way using a third-party program to do everything in GUI, such as the Gnome Control Center.

Third-party tools

sxhkd

A simple X hotkey daemon with a powerful and compact configuration syntax. See sxhkd for details.

actkbd

From actkbd home page:

actkbd^AUR (available in AUR) is a simple daemon that binds actions to keyboard events. It recognises key combinations and can handle press, repeat and release events. Currently it only supports the linux-2.6 evdev interface. It uses a plain-text configuration file which contains all the bindings.

A sample configuration and guide is available here.

xbindkeys

xbindkeys allows advanced mapping of keysyms to actions independently of the Desktop Environment.

Tip: If you find xbindkeys difficult to use, try the graphical manager xbindkeys_config-gtk2^AUR from the AUR.

See also

• Madduck guide on extending XKB^{[dead link 2018-06-01]}