Re: xdvi alternatives

[Norbert Preining <preining@logic.at>]

On Mit, 18 Apr 2007, Frank Küster wrote:
> But doesn't that mean that unless someone (our packages or the local
> admin) unregistered tetex-bin's xdvi, it will show up in the output of
> "u-a --list xdvi.bin", no matter whether the link points there or not?
> And doesn't it make sense to unregister it ("u-a --remove ...") it in
> this case?

Yes. I mixed up something.

I guess the right thing is:
1. if it shows up in --list  =>  remove it
2. if it is in status "manual" AND points to xdvi.real  => set to auto
3. if it is in status "manual" AND points somewhere else => leave
   untouched

The only question is whether 2. could happen. This is what I tried to
solve.

I guess the full code would be:

if update-alternative --list xdvi.bin | grep -q xdvi.real ; then
  # remove the old tetex code, should switch to auto mode automatically
  # even if there are other xdvi alternatives installed (xdvi-ja)
  update-alternatives --remove xdvi.bin /usr/bin/xdvi.real
else
  if update-alternative --display xdvi.bin | grep -q "status is manual" ; then
    if update-alternative --display xdvi.bin | grep -q "link currently points to /usr/bin/xdvi.real' ; then
      # link status is manual, and we point to the tetex alternative
      # can this happen?
      # we switch to auto mode
      update-alternatives --auto xdvi.bin
    else
      # xdvi.bin is in manual mode but not pointing to xdvi.real, leave
      # it untouched
      :
    fi
  fi
fi


Best wishes

Norbert

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Dr. Norbert Preining <preining@logic.at>                    Università di Siena
Debian Developer <preining@debian.org>                         Debian TeX Group
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