Return coding system specified for decoding keyboard input.
(fn &optional TERMINAL)
Specify coding system for keyboard input.
If you set this on a terminal which can't distinguish Meta keys from
8-bit characters, you will have to use ESC to type Meta characters.
See Info node `Terminal Coding' and Info node `Unibyte Mode'.
On non-windowing terminals, this is set from the locale by default.
Setting this variable directly does not take effect;
use either M-x customize or C-x RET k.