Keyboard layout switching/zh-cn

A keyboard layout maps scancodes from a keyboard into characters sent to an application. Keyboard layouts can also do more complex transformations via so called dead keys which do not output characters on their own but modify output of subsequent keys. An appropriate keyboard layout is required to support both non-QWERTY keyboards as well as QWERTY keyboards to enter characters outside of ASCII set.

OpenRC
Edit which is documented but not very understandable. It appears that one should choose an appropriate keyboard map likely from as the value for keymap and then optionally also pick files from an appropriate include directory such as  as values for the extended_keymaps variable:

Lastly add to the boot runlevel.

Custom keymap
To make a custom keymap look at the provided keymaps in :

Here is an example custom keymap which is the same as the U.S. QWERTY keymap, except the forward slash and apostrophe keys are swapped:

To find the keycodes mapped to keys view the output of :

If the key cannot be found using the above command, run:

Just press the key and its keycode will be shown. When finished wait a few seconds and will close.

systemd
systemd uses and includes both terminal font and keyboard layout settings but lacks advanced settings found in OpenRC. Valid values should match what OpenRC supports for the corresponding variable.

X11
Modern X11 applications usually use libXklavier ("klavier" being German for "keyboard") and can be configured by using. Furthermore X11 supports much broader sets of keyboard layouts than is supported for virtual terminals. It should be kept in mind that a proper desktop environment will do its own keyboard layout management. There is no need to directly use the aforementioned application but it can come in handy when dealing with broken or lacking keyboard layout management.

KDE4
Open and navigate to the  module.

Generic desktop environment
Edit and call  from there or setup the keyboard in Xorg configuration file (see below for examples).

lxpanel's keyboard layout handler
provides a keyboard layout handler as a panel item.



Using setxkbmap
These changes are non-permanent and will persist only as long as the user does not restart X11. Naturally the command can be called from a startup script to set the appropriate parameters on every start of the X server.

To query the existing configuration:

Setting a keyboard layout:

Setting a keyboard layout, its variant and model:

Finding the supported layouts and variants or values of other xkb properties does not appear to be possible with this application, although most of them are listed in the file. To get the most complete list seems to be possible only by examining other files in. For sake of sanity, it is advised to use of a proper desktop environment with its own keyboard layout management.

Using system-wide configured layouts and shortcut
This method is recommended for configurations without desktop environments, in other words just X11 with a window manager. Create the file and configure it with the appropriate keyboard settings.

The example above configures US and Brazilian keyboard layouts with + as shortcut to alternate between them. Brazilian layout is signalled by Scroll Lock LED on the keyboard.

Additional configuration possibilities
There are a number of variants and options available which can be used while configuring the keyboard mappings. Most of those can be found in the file.

For example, the US layout with possibility to write some international characters can be configured by using the variant :

is then used as a modifier for typing international characters.

Xorg provides the option to type international and various symbol characters by composition - which means by pressing compose key followed by a sequence of characters. To enable composition add the  option:

The  option above configures  as compose key. With this setting:


 * Press then type 'oo' to get degree sign '°'
 * Press then type 'oc' to get copyright sign '©'
 * Press then type ':)' to get smiling face '☺'
 * Press then type '^2' to get superscript 2 ('²')
 * Press then type '_2' to get subscript 2 ('₂')
 * Press then type 'di' to get diameter sign '⌀'

... and many more. The file lists all possible composition sources.

Enhancing an X keyboard layout
This is necessary when more far-reaching changes have to be made to the keyboard layout, such as adding key assignments, or adding actions to function keys. Since such changes are actually enhancements to the source files of a package, it is recommended to use the epatch_user mechanism so that these amendments are preserved when the package is next updated.

The fundamentals
The relevant Gentoo package is. Configuring a keyboard under X is more complicated than doing the same for a virtual console. The pertinent configuration files can be found in in these subdirectories:


 * These files associate key codes with symbolic names - it is unlikely that anyone wants to change this.
 * These files associate key codes with symbolic names - it is unlikely that anyone wants to change this.


 * This is the physical shape of the keyboard, used by some software for drawing diagrams of it - it is also unlikely that anyone wants to change this.
 * This is the physical shape of the keyboard, used by some software for drawing diagrams of it - it is also unlikely that anyone wants to change this.


 * The files here create "types". Used in a key declaration, a type specifies which combinations of shift keys can be used with the key.
 * The files here create "types". Used in a key declaration, a type specifies which combinations of shift keys can be used with the key.


 * These files specify the actual key assignments.
 * These files specify the actual key assignments.


 * The files here specify "actions" (such as switching to a virtual terminal), giving them names, which can be assigned to keys.
 * The files here specify "actions" (such as switching to a virtual terminal), giving them names, which can be assigned to keys.


 * These files, given parameters such as the keyboard type, and a language, activate the appropriate specifications in the other directories.
 * These files, given parameters such as the keyboard type, and a language, activate the appropriate specifications in the other directories.

A fuller description of the files in these directories can be found at An Unreliable Guide to XKB Configuration by Doug Palmer. It is a lot better than its name suggests. Further documentation can be found at xkeyboard-config's home page at freedesktop.org.

Xkb gives keys names like "" which means "key in the Alphanumeric area, in row C (i.e. third row from the bottom, the row CapsLock is on), and key number 01, the first key at the left of the row". This key is in an English layout. Keys in other areas have other names, such as "" for, or "" for the left control key.

Adding key assignments
As an example, this section will enhance the British English keyboard layout such that typing, , or with  will generate the German umlaut letters ä, ö, and ü. It should also do the Right Thing for the upper case versions. The keys to enhance are (),  () and  (). (The character ß is already assigned to +.)

The names of the umlauted letters in xkb are "adiaeresis" and so on. These names can be found in the file, though the leading "XK_"s have to be removed to get the names.

Identify the right file in the directory. Most of these files are named as two letter country codes (such as for Great Britain) so guess the one which matches the keyboard layout currently selected in X. In this example,  is enhanced.

With the information above, create new entries by copying the existing scheme in. In this example, these entries should be added into the section called "basic". From its content, it is easy to guess that the four items in the braces and brackets within the entry for each key are for regular (without other key combinations),, , and + respectively:

After making the additions, the section looks like this:

Having saved this file, restart X Windows. A typical desktop environment, XFCE, re-reads the above configuration files each time it starts. Should there be errors, error messages will be written to the normal - if X Windows is started from the command line,  will be the virtual terminal it was started from.

Adding actions to function keys
As an example, add the actions "switch to virtual terminal n" (where n > 12) to the function keys -  when, , and  are all selected. The same effect should also occur when and  are selected.

First, search for the file in the directory which handles the existing assignments for the Function keys. This file is. The entry in this file for, which is intended to be modified, is:

There are two things to note with this entry:
 * It is of type "CTRL+ALT"; it thus takes the standard four shift key settings with and, plus a fifth setting of +. Since the goal is to use ++, and there is no suitable existing type, a new one needs to be created.
 * The "action"  is just a defined symbol in the xkb system. Its semantics are given to it by an entry in a file in the  directory, namely . There is no symbol   (or higher) - instead, steal the otherwise unused existing symbols F13, F14, ..., F24.

Creating the new type CTRL+ALT+SHIFT
Having located "CTRL+ALT" in, it is easy enough to copy it, rename the copy to "CTRL+ALT+SHIFT" and extend this to allow the modifier key combination ++. The result looks like this:

Activating the symbols F13, ..., F24
The symbol  is swiftly located in. It is a simple matter to copy its form, creating assignments for the symbols F13, ..., F24. The definition for the first of these symbols, F13, in then looks like:

Analogous definitions for F14, ..., F24 should also be put into the file.

Amending the entries in symbols for keys, ...,
Now that the new type CTRL+ALT+SHIFT and definitions for the symbols F13, ..., F24 are defined, amend the key definitions for the function keys in. The one for is mentioned below, analogous definitions also need to be inserted for the other function keys:

After making these changes to, , and , and restarting the X server, switching from X directly to virtual terminals 13 and above is now possible - provided that these have been configured in the /etc/inittab (or systemd equivalent) of course.