Question

I’d like to insert a timestamp in a custom format in emacs orgmode. I want to insert just the current time (without date!) in this form: [HH:MM], by pressing C-c -. I am completely new to lisp and couldn’t figure out how to do this.
My starting point for my ~/.emacs-file is like this:

(defun org-my-custom-timestamp ()
  (interactive)
  ( :SOME_CODE: )
)


(define-key global-map "\C-c-" 'org-my-custom-timestamp)

Now this is just the definition of my custom function called org-my-custom-timestamp, the “interactivation” and a Shortcut-assignment.
However i have tried various things for :SOME_CODE: without any success.

What can be fitted in the function to make it work in the described way?

Does any experienced emacs-user even consider this way to tackle it practical or is there a smarter way to do it? Perhaps org-mode-internally?

Answer 1

Org mode’s local keymap has an entry that binds C-c -, so we have to change it instead of a global one:

(defun org-my-custom-timestamp ()
  (interactive)
  (insert (format-time-string "[%H:%M]")))
(add-hook 'org-mode-hook
          (lambda ()
            (local-set-key "\C-c-" 'org-my-custom-timestamp)))

Note again that it replaces the org-ctrl-c-minus command, which is bound to C-c - by default in Org mode, with your own.