GNU Emacs Manual. Node: Non-ASCII Rebinding

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28.4.9: Non-ASCII Characters on the Keyboard

If your keyboard has keys that send non-ASCII characters, such as accented letters, rebinding these keys is a bit tricky. There are two solutions you can use. One is to specify a keyboard coding system, using set-keyboard-coding-system (see Specify Coding). Then you can bind these keys in the usual way, but writing

(global-set-key [?char] 'some-function)

and typing the key you want to bind to insert char.

If you don't specify the keyboard coding system, that approach won't work. Instead, you need to find out the actual code that the terminal sends. The easiest way to do this in Emacs is to create an empty buffer with C-x b temp RET, make it unibyte with M-x toggle-enable-multibyte-characters RET, then type the key to insert the character into this buffer.

Move point before the character, then type C-b C-x =. This displays a message in the minibuffer, showing the character code in three ways, octal, decimal and hexadecimal, all within a set of parentheses. Use the second of the three numbers, the decimal one, inside the vector to bind:

(global-set-key [decimal-code] 'some-function)
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