Emacs Keys: Define Key

By Xah Lee. Date: . Last updated: .

How to Assign Key to Command

In emacs, you can create any keyboard shortcut to any command or a Key Macro.

For Emacs 29 (date 2023) , the syntax to change key is this

(keymap-global-set key cmd)

The key is a string of the Key Syntax .

The cmd can be a command name (a Symbol), or a string of Key Macro syntax.

Simply type that code in any buffer, and eval it. The new keybinding is effective immediately. 〔see Emacs: Evaluate Elisp Code〕

Or, you can put the code in Emacs: Init File. If you made some mistake and need to start emacs without loading your init file, see Emacs Init: Ignore Init File.

Example, Emacs 29 or Later

Define a Key for a Command

;; emacs 29 syntax

;; make Ctrl+t call whitespace-mode
(keymap-global-set "C-t" #'whitespace-mode)

Define a Key for Key Macro

;; example for emacs 29, make the f6 key send control-g
(keymap-global-set "<f6>" "C-g")
;; example for emacs 29, make the f6 key insert a string. space between chars are required
(keymap-global-set  "s o m e t h i n g")

Example, Emacs 28 or before

for emacs 28 or before, see 

;; emacs 28 syntax
(global-set-key (kbd "C-t") #'whitespace-mode)

Remove a Keybinding

Emacs 29

;; remove a keybinding

;; for emacs 29 or after
(keymap-global-set "C-t" nil)
;; or use
(keymap-global-unset "C-t")

Emacs 28

;; before emacs 28 or before
(global-set-key (kbd "C-t") nil)
;; or
(global-unset-key (kbd "C-t"))

Find the Command Name of a Given Key

Alt+x describe-key, then type the key combination.

List Current Major Mode Keys

Alt+x describe-mode. 〔see Emacs: Major Mode〕

List ALL Keybinding

Alt+x describe-bindings.

Each Major Mode or Minor Mode usually add or change some keys. So, key list generated is specific to current buffer.

System-Wide Keybinding Setup

best is a programable keyboard:

Reference

Emacs, Change Keys