Shift-Backspace kills X?

Octoploid cryptooctoploid at
Tue Oct 4 23:16:09 PDT 2011

walt <w41ter <at>> writes:
> On 10/04/2011 09:19 AM, Octoploid wrote:
> > walt <w41ter <at>> writes:
> > 
> > (sleep 2 && xmodmap -e "keycode 22 = BackSpace BackSpace BackSpace BackSpace
> > NoSymbol NoSymbol Terminate_Server")&
> That evidently does the same as editing /usr/share/X11/kdb/symbols/terminate
> (thanks for the clue Alan :) but how did you come up with that fix on your own?

Heh, the first thing I've noticed is that Shift-Backspace kills the server.
 % xmodmap -pp -pk | grep Terminate_Server
     22         0xff08 (BackSpace)      0xfed5 (Terminate_Server)       0xff08
(BackSpace)      0xfed5 (Terminate_Server)
I then figured out that the second entry above (0xfed5) must be responsible
for this.

There are 7 keysymbols per keycode. (Just look at the first line of):
% xmodmap -pp -pk
There are 7 KeySyms per KeyCode; KeyCodes range from 8 to 255

So I started with:
xmodmap -e "keycode 22 = BackSpace BackSpace BackSpace BackSpace
Terminate_Server Terminate_Server Terminate_Server"
and then finally arrived at the fix posted before (it works, but 
differs from editing /usr/share/X11/kdb/symbols/terminate, which is
identical to:
xmodmap -e "keycode 22 = BackSpace VoidSymbol BackSpace VoidSymbol VoidSymbol
VoidSymbol Terminate_Server")

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