Enjoying Open Source Software

Turn Capslock into Control key on a Thinkpad X270 running FreeBSD

FreeBSD 13 on a Thinkpad X270

Recently I bought a refurbished Thinkpad X270 with an 1900x1080 display and installed FreeBSD 13.0 on it.

FreeBSD on the Thinkpad X270 is a great combination.

Thinkpad keyboards

Thinkpads are known to have great keyboards. And a trackpoint. Typing on a Thinkpad is great.

But there are some strange design decisions.

Lenovo puts six-row keyboards in Thinkpads, which means that the Function keys also function as media keys (muting sound, increasing or decreasing the sound volume, increasing or decreasing the display backlight, and so on). To switch between these two functionalities, there is a Fn key on the keyboard.

This Fn key is placed left of the left Ctrl key. So when you are used to a the left most key on your keyboard being the Ctrl key, your muscle-memory gets confused.

Exchange the Fn key and the left Control key

After a couple of days I switched the Fn and the Ctrl key. There is an option in the Lenovo BIOS for that.

No Capslock light

Lenovo thought it is a good idea to give you no feedback at all on the state of the Capslock key.

Maybe if you are running Windows on it, there is some kind of software feedback mechanism, I don't know, because I have never run Windows on it.

Keyboard Lights

There is a green LED in the Fn key, and a red LED in the mute media key as well as in the microphone kill media key.

But there is no LED in the Capslock key, only Lenovo knows why.

Weird behavior

I use mostly keyboard controlled software, like the suckless dwm window manager, and Vim and Emacs. So things can suddenly start to go crazy, when the Capslock is accidentally "on".

This eventually made me decide to ditch the capslock-functionality and alter the configuration to make the Capslock behave like a Control key.

Turn Capslock into Control

After some searching, I came to this solution.


I have added the following line in my .xinitrc:

setxkbmap -model thinkpad -layout us -option caps:ctrl_modifier

Now, the Capslock key just functions as an extra Control key, and accidentally touching the Capslock key have no consequences :)