38

I'd like to exchange Esc and CapsLock in console (not in X, and use xev), how can I do it?

My OS is Ubuntu.

Kevin Panko
  • 7,346
  • 22
  • 44
  • 53
Vayn
  • 491
  • 1
  • 6
  • 7

2 Answers2

68

The tools to manipulate the keyboard layout on the virtual consoles are loadkeys, dumpkeys and showkey. Read their manpages and inform yourself about their intricacies.

Note that these tools only work in a virtual console, not in a terminal emulator in a graphical environment like gnome. The learn about the difference read this question and answers.

Here is a short guide to do what you want:

  1. Save your current keyboard layout:

     $ dumpkeys > backup.kmap

    In case something goes wrong you might be able restore your keymap using the command:

     $ sudo loadkeys backup.kmap

    If the keyboard is so messed up that you can't even do this then your only option not involving ancient kernel magic is to reboot.

  2. Check which keycodes are assigned to your keys:

     $ showkey

    Now press the ESC key and the CAPSLOCK key. The keycodes should show up on the screen. Note the keycodes. On my system the ESC has the keycode 1 and CAPSLOCK has the keycode 58. showkey will terminate after 10 seconds of inactivity (at least it does on my ubuntu 10.04).

  3. Note the names of the ESC and CAPSLOCK keys from dumpkeys:

     $ dumpkeys | grep 1
 ...
 keycode   1 = Escape
 ...
 $ dumpkeys | grep 58
 ...
 keycode  58 = CtrlL_Lock
 ...

  4. Note the keymap line from dumpkeys:

     $ dumpkeys | head -1
 keymaps 0-127

  5. Create a keymap file which switches ESC and CAPSLOCK:

     keymaps 0-127
 keycode   1 = CtrlL_Lock
 keycode  58 = Escape

  6. Load the keymap:

     $ sudo loadkeys swap_esc_capslock.kmap

  7. Test: Testing the CAPSLOCK key is obvious. Just press they CAPSLOCK key and check whether other keys come out capitalized. To test the ESC key you can use CTRL+V followed by ESC. It should print ^[. CTRL+V makes the shell print the next key verbatim instead of interpreting it.

To have this modification load on every reboot, put the following line in your /etc/rc.local file:

/usr/bin/loadkeys /path/to/swap_esc_capslock.kmap

Information gathered from various pages, including, but not limited to:

Bazer Con
  • 13
  • 2
Lesmana
  • 19,803
  • 6
  • 45
  • 44
  • 5
    You can also use `sudo setupcon --save` to make changes permanent, rather than editing rc.local. That's essentially the same as `dumpkeys < /dev/tty1 | gzip > /etc/console-setup/cached.kmap.gz` – bukzor May 21 '12 at 02:21
  • It is safer to use `/usr/bin/loadkeys` in `/etc/rc.local`since the path environment variable is not guaranteed to be set at this stage. And `sudo` is not needed in `rc.local`. – August Karlstrom May 07 '13 at 20:04
  • @AugustKarlstrom The command in `rc.local` executes every time the system boots. @bukzor's `sudo setupcon` is _not_ in `rc.local`, it's a one-time setup command, which replaces the system default keymap, without adding any runtime startup code. Adding `loadkeys` to `rc.local`, adds extra start up code and duplicates what was already done by the system default loadkeys. The `rc.local` method could actually be less safe because it depends on a non-standard path to the keymap. – RobertL Nov 11 '15 at 21:04
  • I cannot verify @bukzor's statement about `setupcon`. It appears that August made the assumption that the `sudo setupcon --save` would go into `rc.local` which I don't think is true, but if it does, you don't need `sudo` in `rc.local`. I think we need more info before updating your answer. The main question is "How to install the modified keymap so that it gets loaded automatically during the boot process?" I really don't know which is a better way, `rc.local` or installing a keymap, or even if installing a keymap will work. I have been researching this lately and I'll check back here. – RobertL Nov 12 '15 at 03:21
  • the `showkey` command isn't working for me as described. when I run it, I get a warning: "[ if you are trying this under X, it might not work since the X server is also reading /dev/console ]". It still gives me the prompt to "press any key" but no key codes show up, just the character itself (i.e. 'a' appears if I press the 'a' key, and nothing happens at all if I press "Caps Lock"). help!! – sixty4bit Sep 27 '16 at 15:01
  • 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. – user3751385 Sep 06 '18 at 16:17
  • If you’re worried about having to reboot if you mess up your keyboard, note that you can also restore the keyboard over an SSH session: `sudo loadkeys --console=/dev/tty3 < …` – andrew.n Feb 28 '21 at 18:56
4

Use ctrl:nocaps instead of ctrl:swapcaps if you just want to have two capslocks key (capslock by another name is still super useless).

X11: (see also: /usr/share/X11/xkb/rules/base.lst)

sudo vim /etc/default/keyboard
    XKBOPTIONS="ctrl:swapcaps"
udevadm trigger --subsystem-match=input --action=change
sudo restart lightdm

Text console: (stolen from setupcon)

#!/bin/sh
. /etc/default/console-setup 
. /etc/default/keyboard
ckbcomp $acm_option $rules_option -model "$XKBMODEL" \
            "$XKBLAYOUT" "$XKBVARIANT" "$XKBOPTIONS" \
            | gzip -9 2>/dev/null >/etc/console-setup/cached.kmap.gz
loadkeys /etc/console-setup/cached.kmap.gz
Bazer Con
  • 13
  • 2
bukzor
  • 2,094
  • 2
  • 16
  • 21