Re: [Qemu-devel] [PATCH] input-linux: customizable grab toggle keys v4

[Gerd Hoffmann <kraxel@redhat.com>]

On Sat, Jan 19, 2019 at 11:14:27PM -0500, Ryan El Kochta wrote:
> This patch adds a new option to the input-linux object:
> 
> grab-toggle=[key-combo]
> 
> The key combination can be one of the following:
> 
> * ctrl-ctrl

left ctrl + right ctrl.

> * alt-alt

Same.

> * meta-meta

Same.

> * ctrl-alt

This is actually left ctrl + left alt (not any ctrl / alt) in the code.

Ctrl+Alt+Key isn't that uncommon as hotkey, linux console switching uses
Ctrl+Alt+Fn for example.  Also some GUI apps use Ctrl+Alt+Someletter for
less frequently used functions when they run out of Ctrl+Someletter
hotkeys.  I'd suggest to drop this one.

> * scrolllock
> * ctrl-scrolllock

This likewise is actually left ctrl + scrolllock in the code.

> * ctrl-backtick

Not a good idea.  backtick has no fixed location, depends on the
keyboard layout.

So, the naming is a bit tricky here.  If only the left ctrl key actually
works we should say so in the name and call it "lctrl-scrolllock".  Or
leave the name and allow both ctrl keys.

For the ctrl-ctrl (and simliar) hotkeys I think it doesn't matter much
whenever we call them "ctrl-ctrl" or "lctrl-rctrl".  It is kida obvious
that you need both the left and right one when you should press two
control keys.  But I think it should be consistent with what we pick for
ctrl-scrolllock.

I think sticking with the current names and make both ctrl keys work
with scrolllock is the better way.

cheers,
  Gerd