Linux console/Keyboard configuration

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Keyboard mappings (keymaps), console fonts and console maps for the Linux console are provided by the kbd package (a dependency of systemd), which also provides many low-level tools for managing text console. In addition, systemd also provides the localectl tool, which can control both the system locale and keyboard layout settings for both the console and Xorg.

Viewing keyboard settings

Use localectl status to view the current keyboard configurations.

Keymaps

The keymap files are stored in the /usr/share/kbd/keymaps/ directory tree. Usually one keymap file corresponds to one keyboard layout (the include statement can be used to share common parts and a keymap file can contain multiple layouts with some key combination used for switching). For more details see keymaps(5).

Listing keymaps

The naming conventions of console keymaps are somewhat arbitrary, but usually they are based on:

For a list of all the available keymaps, use the command: 

$ localectl list-keymaps

To search for a keymap, use the following command, replacing search_term with the code for your language, country, or layout: 

$ localectl list-keymaps | grep -i search_term

Alternatively, using find: 

$ find /usr/share/kbd/keymaps/ -type f -name "*search_term*"

Loadkeys

It is possible to set a keymap just for current session. This is useful for testing different keymaps, solving problems etc.

The loadkeys tool is used for this purpose, it is used internally by systemd when loading the keymap configured in /etc/vconsole.conf. It can be used very simply for this purpose: 

# loadkeys keymap

See loadkeys(1) details.

Persistent configuration

A persistent keymap can be set in /etc/vconsole.conf, which is read by systemd on start-up. The KEYMAP variable is used for specifying the keymap. If the variable is empty or not set, the us keymap is used as default value. See vconsole.conf(5) for all options. For example: 

/etc/vconsole.conf
KEYMAP=uk
...

For convenience, localectl may be used to set console keymap. It will change the KEYMAP variable in /etc/vconsole.conf and also set the keymap for current session: 

# localectl set-keymap --no-convert keymap

The --no-convert option can be used to prevent localectl from automatically changing the Xorg keymap to the nearest match. See localectl(1) for more information.

If required, the keymap from /etc/vconsole.conf can be loaded during early userspace by the keymap mkinitcpio hook.

Tip: If you saved your custom keymap somewhere other than /usr/share/kbd/keymaps/, it must be specified by a full path to the file in vconsole.conf or when using the localectl command above.

Creating a custom keymap

When using the console, you can use hotkeys to print a specific character. Moreover we can also print a sequence of characters and some escape sequences. Thus, if we print the sequence of characters constituting a command and afterwards an escape character for a new line, that command will be executed.

One method of doing this is editing the keymap file. However, since it will be rewritten anytime the package it belongs to is updated, editing this file is discouraged. It is better to integrate the existing keymap with a personal keymap. The loadkeys utility can do this.

First, create a keymap file. This keymap file can be anywhere, but one method is to mimic the directory hierarchy in /usr/local: create the /usr/local/share/kbd/keymaps directory, then edit /usr/local/share/kbd/keymaps/personal.map.

As a side note, it is worth noting that such a personal keymap is useful also to redefine the behaviour of keys already treated by the default keymap: when loaded with loadkeys, the directives in the default keymap will be replaced when they conflict with the new directives and conserved otherwise. This way, only changes to the keymap must be specified in the personal keymap.

Tip:
  • You can also edit an existing keymap located in the /usr/share/kbd/keymaps/ directory tree. Keymaps have an .map.gz extension, for example us.map.gz is an American keymap. Just copy the keymap to /usr/local/share/kbd/keymaps/personal.map.gz and gunzip it.
  • The custom keymap can be made persistent by setting it in /etc/vconsole.conf. Given this, if you use the sd-vconsole mkinitcpio hook instead of keymap, you could place your custom keymap file in /usr/share/kbd/keymaps/. This way its dependencies from /usr/share/kbd/keymaps will be automatically added to the initial ramdisk image by the hook. On the other hand, if you place your custom keymap file under /usr/local/, then its dependencies will need to be manually specified in the FILES array in mkinitcpio.conf.

Adding directives

Two kinds of directives are required in this personal keymap. First of all, the keycode directives, which matches the format seen in the default keymaps. These directives associate a keycode with a keysym. Keysyms represent keyboard actions. The actions available include outputting character codes or character sequences, switching consoles or keymaps, booting the machine, and many other actions. The full currently active keymap can be obtained with 

# dumpkeys -l

Most keysyms are intuitive. For example, to set key 112 to output an 'e', the directive will be: 

keycode 112  = e

To set key 112 to output a euro symbol, the directive will be: 

keycode 112 = euro

Some keysym are not immediately connected to a keyboard actions. In particular, the keysyms prefixed by a capital F and one to three digits (F1-F246) constituting a number greater than 30 are always free. This is useful directing a hotkey to output a sequence of characters and other actions: 

keycode 112 = F70

Then, F70 can be bound to output a specific string: 

string F70 = "Hello"

When key 112 is pressed, it will output the contents of F70. In order to execute a printed command in a terminal, a newline escape character must be appended to the end of the command string. For example, to enter a system into hibernation, the following keymap is added: 

string F70 = "sudo systemctl hibernate\n"

Other examples

  • To make the Right Alt key same as Left Alt key (for Emacs), use the following line in your keymap. It will include the file /usr/share/kbd/keymaps/i386/include/linux-with-two-alt-keys.inc, check it for details.
include "linux-with-two-alt-keys"
  • To swap CapsLock with Escape (for Vim), remap the respective keycodes:
keycode 1 = Caps_Lock
keycode 58 = Escape
  • To make CapsLock another Control key, remap the respective keycode:
keycode 58 = Control
  • To swap CapsLock with Left Control key, remap the respective keycodes:
keycode 29 = Caps_Lock
keycode 58 = Control

Saving changes

In order to make use of the personal keymap, it must be loaded with loadkeys: 

# loadkeys /usr/local/share/kbd/keymaps/personal.map

However this keymap is only active for the current session. In order to load the keymap at boot, specify the full path to the file in the KEYMAP variable in /etc/vconsole.conf. The file does not have to be gzipped as the official keymaps provided by kbd.

Adjusting typematic delay and rate

The typematic delay indicates the amount of time (typically in milliseconds) 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. These values can be changed using the kbdrate command. Note that these settings are configured separately for the console and for Xorg. 

# kbdrate [-d delay] [-r rate]

For example to set a typematic delay to 200ms and a typematic rate to 30Hz, use the following command: 

# kbdrate -d 200 -r 30

Issuing the command without specifying the delay and rate will reset the typematic values to their respective defaults; a delay of 250ms and a rate of 11Hz: 

# kbdrate

Systemd service

A systemd service can be used to set the keyboard rate. For example: 

/etc/systemd/system/kbdrate.service
[Unit]
Description=Keyboard repeat rate in tty.

[Service]
Type=oneshot
RemainAfterExit=yes
StandardInput=tty
StandardOutput=tty
ExecStart=/usr/bin/kbdrate --silent --delay 250 --rate 30
 
[Install]
WantedBy=multi-user.target

Then start/enable the kbdrate.service systemd service.