Re: ash vs. bash
> > > Easy. Manage /bin/sh by update-alternatives.
> >
> > No. update-alternatives is too fragile for this role. (If /bin/sh
> > breaks, the system is pretty dead.)
>
> What makes two links more fragile than one link? update-alternatives works
> pretty well, and it is non-obstrusive: If you change the link, it will
> notice and take a step back.
Read the code, realise how long there is and how many <do X> || die
commands there are between deleting the old link and installing the
new one, and it will be obvious. It's not a question of two links
rather than one, but a question of "what happens if
update-alternatives fails for some reason"?
> Anyway, even if update-alternatives has still bugs (which could be fixed),
> fixing this will reuqire just a boot disk, one mount command and one
> symbolic link, or one option to LILO. Still, I have yet to see serious
> problems with update-alternatives, that would be relevant in this
> discussion. Anyway, I would volunteer to take a look at update-alternatives
> and the reported bugs as well.
>
> The system is far from dead. It won't come up nicely, but is easy to fix.
It may be easy for someone extremely competent to fix (that is, you
know what's wrong and how to go about fixing it). But it's not at all
easy if you don't even know where to begin.
> I can't see how you can trust ldconfig if you are suspicious about
> update-alternatives.
ldconfig removes the old link and immediately tries installing the new
link if the removal was successful. The only thing that could go
wrong is if the one old link is removed and the new one cannot be
installed. And you are right: it might be a problem one day. But we
need not exacerbate such a problem.
Julian
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Julian Gilbey, Dept of Maths, QMW, Univ. of London. J.D.Gilbey@qmw.ac.uk
Debian GNU/Linux Developer, see http://www.debian.org/~jdg
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