Re: Bug#161455: debian-policy: reference to ash outdated
On Thu, Sep 26, 2002 at 08:15:58AM -0400, Anthony DeRobertis wrote:
> On Fri, 2002-09-20 at 05:28, Julian Gilbey wrote:
>
> >
> > Technical problems here. Among other things, you'd have symlinks
> > /bin/sh -> /etc/alternatives/sh -> /bin/<something>
> > What happens if /etc is corrupted or not mounted or there are other
> > problems?
>
> Nothing worse than what happens if you put /etc on a filesystem other
> than / without some pretty evil kluges...
>
> (hint: /etc/fstab)
True ;-)
> > Also, there is another major problem with using update-alternatives:
> > we must *always* have a working /bin/sh, so it must be included in an
> > essential package. But then we can't use alterternatives, which have
> > to be organised from the maintainer scripts.
>
> Yep. This a more serious problem. I don't think its unsolvable, though;
> how does the current /bin/sh link get set up? I'd think bash postinst
> could change it to an alternative, but this leaves the problem of if
> update-alternatives requires a working /bin/sh
The current link is part of the bash package. The preinst checks
whether this either points to bash (or /bin/bash) and if not, that it
is diverted using dpkg-divert. If neither of these are the case, the
admin is warned of this and the link is reset to bash.
Note that alternatives are handled from maintainer scripts and
diversions from within dpkg itself (as well as via alternatives).
I don't know the full rationale.
Julian
--
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Julian Gilbey, Dept of Maths, Queen Mary, Univ. of London
website: http://www.maths.qmul.ac.uk/~jdg/
Debian GNU/Linux Developer, see: http://people.debian.org/~jdg/
Visit http://www.thehungersite.com/ to help feed the hungry
Reply to: