showkey(1) on Linux
The text 312fca2887b4, as Debian 12 (Bookworm), Debian 11 (Bullseye) shipped it.
examine the codes sent by the keyboard
Flags it lists
-
--ascii -
--help -
--keycodes -
--scancodes -
--version -
-V -
-a -
-h -
-k -
-s