I'm trying to reset the binding for "C-x C-c". Specifically, I want to rebind it to a function that asks me if I really want to quit (I just fat finger it way too much). I've done this before under Linux with no issues. Under Mac OS X, when I evaluate the expression

(global-unset-key “\C-x\C-c”)

I get:

eval-buffer: Symbol's value as variable is void: “C-xC-c”

So, why is it void? The command does exit Emacs, so it can't be void. I must not be referring to "C-x C-c" correctly. But what is the correct way?

I get the same problem when using global-set-key to bind the command sequence to a new function.

I'm using GNU Emacs 23.0.0 from MacPorts and Mac OS X 10.5 (Leopard).

3 Answers 3


Somehow, you are using smartquotes.


(global-unset-key "\C-x\C-c")  ;; use this

instead of

(global-unset-key “\C-x\C-c”)  ;; Not this one!
  • This was the problem. I copied the code from a website. Somehow, all the quotes (single and double) became smartquotes.
    – Rob Jones
    Sep 10, 2009 at 17:32
  • 2
    A fair number of websites (say, all the WordPress blogs in the world that haven't been tweaked) will force change all quotes to smart-quotes. It's a plague for code copying.
    – Telemachus
    Sep 28, 2009 at 17:23

Emacs has a configuration for what you asked that does not require to touch the C-x C-c binding.

Just add to your config one of the following:

(setq confirm-kill-emacs 'y-or-n-p)

(setq confirm-kill-emacs 'yes-or-no-p)

The first one will you ask you to type a single character y/n for confirmation, while the second one will ask you the full answer yes/no.


This is a start, here is a somewhat relevant page http://www.delorie.com/gnu/docs/emacs/emacs_496.html , but it seems what you want is to redefine the binding, not to remove it. Or just always have a modified file around, that way it will ask before quitting (and you could automate that in your .emacs or ~/.emacs.d/init.el )


  • Those don't help much. I know what I want to do, and I'm fairly confident I'm going about it in the right manner. I don't understand how to represent C-x C-c. What I think I've used in the past is not working here.
    – Rob Jones
    Sep 10, 2009 at 3:17
  • That is a really old manual. The OP is on Emacs 23. C-h i, or if you really want to read it on the web, gnu.org/software/emacs/manual/emacs.html Sep 10, 2009 at 4:50

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