I mean C-?, which in qwerty is control-shift-/.

On Wed, 17 Oct 2018, 14:00 Garreau, Alexandre, <galex-713@galex-713.eu>
wrote:

> On 2018-10-17 at 12:09, Nathan Moreau wrote:
> > From my experience with undo-tree, C-S-/ is a good binding.
> > It is easy to reach right after hitting undo (C-/). Direct access is a
> > little bit hard but you don't tend to press it directly that often.
>
> Are you really meaning shift when saying S- (or maybe super? which is
> usually not accessible to emacs unless you use it as a window manager
> through exwm)? Then what is your keyboard layout?
>
> In qwerty and dvorak: S-/ is ?, so C-S-/ is C-?, which is impossible to
> type (it gives ? usually), while corresponding to DEL under a terminal.
>
> In azerty: / is already accessed with shift.
>
> In bépo: S-/ is 9, so C-S-/ is C-9 and is already bound to
> `digit-argument'
>