xkbutils is a collection of small utilities utilizing the XKeyboard (XKB)
extension to the X11 protocol.

It includes:
 xkbbell  - generate XKB bell events
 xkbvleds - display the state of LEDs on an XKB keyboard in a window
 xkbwatch - reports changes in the XKB keyboard state

Homepage:
https://xorg.freedesktop.org/
