Check Lock Keys state from command-line

Question

I want to check Lock keys (i.e Caps Lock, Num Lock, Scroll Lock etc.) state (On/Off) from command-line. How do I check state via terminal command?

Answer 1

simply run:

xset q

From man xset:

q       The q option gives you information on the current settings.

In the top section of the output, you will find your information, looking like:

Keyboard Control:
  auto repeat:  on    key click percent:  0    LED mask:  00000003
  XKB indicators:
    00: Caps Lock:   on     01: Num Lock:    on     02: Scroll Lock: off
    03: Compose:     off    04: Kana:        off    05: Sleep:       off
    06: Suspend:     off    07: Mute:        off    08: Misc:        off
    09: Mail:        off    10: Charging:    off    11: Shift Lock:  off
    12: Group 2:     off    13: Mouse Keys:  off

---

You can use grep to get specific result as follows:

$ xset -q | grep Caps
    00: Caps Lock:   off    01: Num Lock:    on     02: Scroll Lock: off 

Answer 2

With xset you could use the following sed command:

xset -q | sed -n 's/^.*Caps Lock:\s*\(\S*\).*$/\1/p'

As an example, say you want to check if caps lock is enabled, and if so to disable it. For that you could do:

caps_lock_status=$(xset -q | sed -n 's/^.*Caps Lock:\s*\(\S*\).*$/\1/p')
if [ $caps_lock_status == "on" ]; then
  echo "Caps lock on, turning off"
  xdotool key Caps_Lock
else
  echo "Caps lock already off"
fi

Answer 3

If you're not in X ("graphical mode"), but in a terminal:

$ /usr/bin/setleds
Current default flags:  NumLock off   CapsLock off   ScrollLock off
Current flags:          NumLock off   CapsLock off   ScrollLock off
Current leds:           NumLock off   CapsLock off   ScrollLock off

Similarly, if you want to know the state of a terminal, but you're not in it (e.g. you came in through SSH):

setleds < /dev/tty1

You might need to be root, due to /dev/tty* permissions.

See the man page for more (the command can even set the leds, reading them is just a side effect).