l i n u x - u s e r s - g r o u p - o f - d a v i s
Next Meeting:
July 7: Social gathering
Next Installfest:
Latest News:
Jun. 14: June LUGOD meeting cancelled
Page last updated:
2004 Aug 13 16:57

The following is an archive of a post made to our 'vox-tech mailing list' by one of its subscribers.

Report this post as spam:

(Enter your email address)
Re: [vox-tech] Debian Unstable - apt strangeness
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [vox-tech] Debian Unstable - apt strangeness

Quoting David Hummel (dhml@comcast.net):

> dpkg must know about available packages since:
> $ dpkg -l package-name-pattern
> lists available packages (apparently from /var/lib/dpkg/available)
> regardless of whether they're installed.

Perhaps I was a bit unclear:  dpkg knows only about what's in
/var/lib/dpkg/status.  It can glean information about uninstalled
packages from that file only because apt puts that data there.

The wording of Peter's post suggested he might be unaware of the
segmentation of roles between the two programs.  So, I detailed the
difference:  apt fetches but doesn't install; dpkg installs but doesn't
fetch.  (apt must therefore invoke dpkg to complete package
installation.)  Clearer?

I was extremely vaguely aware that /var/lib/dpkg/status includes stanzas
about uninstalled packages, but that fact tends to slip my mind because
I don't use it:   The useful way to use "dpkg -l ..." is without globs,
which, for reasons I haven't looked into, omits uninstalled packages
from the return values.  Which is what I said before.

> Therefore, it's a bit misleading that dpkg -l with no
> package-name-pattern only lists installed packages.
> So how is /var/lib/dpkg/available generated if not from apt?

I'm utterly mystified as to how you could think I said otherwise.

apt pulls down (among other things) *Packages files from the various
sources into /var/lib/apt/lists, then merges them to form a single
/var/lib/dpkg/available file.  _Of course_ it's generated by apt.

vox-tech mailing list

LUGOD Group on LinkedIn
Sign up for LUGOD event announcements
Your email address:
LUGOD Group on Facebook
'Like' LUGOD on Facebook:

Hosting provided by:
Sunset Systems
Sunset Systems offers preconfigured Linux systems, remote system administration and custom software development.

LUGOD: Linux Users' Group of Davis
PO Box 2082, Davis, CA 95617
Contact Us

LUGOD is a 501(c)7 non-profit organization
based in Davis, California
and serving the Sacramento area.
"Linux" is a trademark of Linus Torvalds.

Sponsored in part by:
EDGE Tech Corp.
For donating some give-aways for our meetings.