[Tfug] fhs on /var/cache (debian)

[t takahashi]

On 7/23/06, John Gruenenfelder <johng at as.arizona.edu> wrote:
> Are you sure it's the package manager or just apt?  Apt is just a frontend
> to
> the package manager, dpkg, and as such is not a "critical" component.  dpkg
> does not appear to have any data under /var/cache.

i use apt-get and aptitude for most things, and only drop down to dpkg
when i can't do something without it.  if you know how to emulate
apt-get with dpkg, complete with dependencies, i will try that and let
you know.

the claim to attempt to comply with fhs is not contingent on the
criticality of the component that i know of.  can you point to where
it is?  (no need to look it up; just a rough recollection will do.)

> Looking at my system's /var/cache I see only /var/cache/apt and
> /var/cache/debconf which have anything to do with packages.

good point about dpkg, but i think most users use front ends to dpkg.
for that matter, many users with backup media constraints will believe
the fhs promise to be enough and not back up /var/cache.  should they
be so trusting?  clearly not, but they will be.

again, i'd be interested in doing the equivalent of apt-get update;
apt-get upgrade (or aptitude upgrade) without apt, if you know how.
i.e. with the identical results.  i wonder if somebody has written a
shell script.

> I agree that debconf data seems a little out of place there... Seems like
> /etc
> would be a better place for it.

i'd pick /var/lib, but /etc is plausible too.

> As for /var/cache/apt, that is entirely transitory data.  Doing an "apt-get
> update" should be enough to regenerate it, I believe.  Of course, that
> doesn't
> mean it's okay to bomb horribly when those files are missing...

oh, and the tools do bomb, one by one.  seems like the programming
ethic of checking for stuff before doing things that depend strongly
on that stuff to even bomb reasonably isn't quite as strong as we
might like for basic system tools.  (by "bomb reasonably" i mean
giving the user more than "segmentation exception".)  the developers
had higher priorities, i guess.

> --John Gruenenfelder    Research Assistant, UMass Amherst student
>                         Systems Manager, MKS Imaging Technology, LLC.

remote student or remote tfugger?

-- 
Webmaster: do you believe that people will (a) switch browsers to view
your "best viewed with" page or (b) go to your competitor?