How to highlight keyboard led using current locale

Question

How does one make the keyboard led show his current locale? It might be useful for users using two locales (languages).

Desired behavior:

• capslock led on keyboad is OFF for your first locale (english, for example)
• capslock led is ON for your second locale (russian, for example)
• capslock led changes when you're switching windows (from a window with "ru" to a window with "en")

Answer 1

A solution for a debian-based distribution:

• run dpkg-reconfigure keyboard-configuration. You can set up the capslock switching here (altrough it would not activate keyboard led by default). (Skip for non-debian distr.)
• open /etc/default/keyboard (find an alternative for non-debian distr.)
• find XKBLAYOUT. You should see something like "us,ru" inside. If not, edit this line.
• find XKBOPTIONS. Set this inside: grp:caps_toggle,grp:switch,grp_led:caps. The caps_toggle and switch mean switching layout by capslock (skip if you only want keyboard led, not switching). The grp_led:caps means to use the led for layout indication.
• reboot the system or apply changes immediately if you know how. For debian-based distros it's dpkg-reconfigure keyboard-configuration.