August 27, 2024

Remapping the key Caps Lock as Ctrl on GNU/Linux

This is about remapping the key Caps Lock as Ctrl.

I looked around the web and found a few ways to do it; editing XKBOPTIONS worked on my system (i.e. GNU/Linux Trisquel, Xfce). I have no idea whether this is the best way.

To remap the key, I appended ctrl:swapcaps to XKBOPTIONS in the file /etc/default/keyboard

I went from this:

XKBOPTIONS="grp:toggle,grp_led:scroll"

to this:

XKBOPTIONS="grp:toggle,grp_led:scroll,ctrl:swapcaps"

Then I ticked the checkbox Use system keyboard layout, if you hover you’ll see the XKB acronym (prepending XKBOPTIONS).

What is XKBOPTIONS?

From the manpages of keyboard:

[XKBOPTIONS] specifies the XKB keyboard option components. Options usually relate to the behavior of the special keys (Shift, Control, Alt, CapsLock, etc.) Default: not set.

Also see from the section title EXAMPLES:

The following configuration will give you the standard US QWERTY layout (us). The key Menu will act as a compose key (compose:menu) and CapsLock, will act as third control key (ctrl:nocaps).

XKBLAYOUT=us

XKBVARIANT=

XKBOPTIONS=compose:menu,ctrl:nocaps

In this example, you can see that if you want to keep the behaviour of the key left Ctrl as it is, you can try appending XKBOPTIONS with ctrl:nocaps (instead of ctrl:swapcaps. I have not tried myself).

Note: you need to edit the configuration file with sudo:

$ sudo vi /etc/default/keyboard

or

$ sudo nano /etc/default/keyboard

Source: keyboard manpage.

personal computing command-line interface (cli) gnu linux trisquel shell literacy wiki xfce