Idea: When users press Ctrl+Alt+Bksp, tell them the new way to kill Xorg

[Timothy Normand Miller]

On Fri, Dec 4, 2009 at 1:44 PM, Jason Spiro <jasonspiro4+gmane at gmail.com> wrote:
> Alan Coopersmith <Alan.Coopersmith at ...> writes:
>
>> The X server has no way of displaying a message to users.   It could possibly
>> log a message to Xorg.0.log which some may see, but probably not many.   If
>> it's in a state in which the user needs to use Ctrl-Alt-Backspace to kill it,
>> then it's probably not going to be able to fork a new client and have the
>> window manager place it and map it.
>
> Often it *can* fork a new client.  For example, users often use Ctrl+Alt+Bksp
> as a quick way to log out, and may wonder why it doesn't work in recent
> versions of Xorg.  This would give them a quick answer.

What do you do if something's gone wrong with the virtual terminals?
I've had this happen plenty of times in the past.  Broken driver (in X
or kernel) doesn't restore VGA or the graphical console, so you get a
blank screen.  Despite that, exiting X will somehow cause the console
to get restored.  Although X is far better than it was in the past, I
can't accept that it now never has this problem.  Then we have to
delve into suggestions like remote login, assuming that's even enabled
in the firewall, the user has another machine available, etc.

No, switching virtual consoles is not a universal solution to this
problem.  The universal solution is the reset button (assuming you
have a journaling file system) and quick fingers to edit the grub
command line so that you can enter single user mode and manually poke
around in the config files because obviously, the graphical
configuration isn't going to work.  Of course, that's a non-solution
for anyone who doesn't know how to do that.  Like me.  I've done it
plenty of times, but I have to google it every time.

None of this, of course, is necessarily an argument in favor of
ctrl-alt-backspace.  It's a convenient way to kill X, but that too is
not any kind of universal solution.  What about those cases when the
text console is not restored on exit?  And if you had a problem with
"X -configure", and ctrl-alt-backspace does work and exit you back to
the console, that doesn't solve the problem of being unable to
configure X, which is unrelated to the key combination.

Maybe X needs a watchdog timer for hangs and more robustness in
dealing with crashes, drivers that don't work, and other config
issues.  I've noticed that X now works perfectly for me with no
xorg.conf at all, which is impressive.  So it's really getting to the
point where fewer and fewer people will have to deal with any of these
issues at all.

Kernel mode setting actually solves a LOT of problems, because now,
when X crashes, the kernel can restore the graphics card state.

Also, ctrl-alt-backspace doesn't do you any good when your problem is
your keyboard input driver.  I use Gentoo, and sometimes when the core
is updated, the evdev driver doesn't work without a recompile.

And finally, I worked with X11 for a really long time before there was
any such key combination.  People just suffered.  Then someone decided
to add this feature, and it saved some of us a lot of trouble.  Mostly
developers, but we always had remote login anyhow.  Now people are
changing their minds.  Oh well.

-- 
Timothy Normand Miller
http://www.cse.ohio-state.edu/~millerti
Open Graphics Project