Bug#155195: apt: wish: apt-cache --locally-installed-packages-only option

[era eriksson <era@iki.fi>]

Package: apt
Version: 0.5.4
Severity: wishlist

It would be nice if apt-cache output could be constrained to only show
packages which are installed locally. The particular use case which
motivates this request is the recent debian-security-announce security
bulletins, which suggest running

  apt-cache showpkg (vulnerable package)

to see what packages are affected by the vulnerability -- however in
some recent cases, the listing is way too big to be really useful, and
most sites will only have a small fraction of all the packages which
are affected, so it doesn't really show you whether you are actually
affected or not.

(Granted, if you have a library installed, chances are +something+ you
have on your system depends on it, but let's say you have a single
package which is not actively used -- then you'd probably rather ditch
them both and avoid any future security problems with the same
library.)

The suggested long option name is obviously too long; perhaps you can
come up with something more succinct.

Thanks in advance for considering this,

/* era */

-- System Information
Debian Release: 3.0
Kernel Version: Linux there.afraid.org 2.2.17 #1 Sun Jun 25 09:24:41 EST 2000 i586 unknown

Versions of the packages apt depends on:
ii  libc6          2.2.5-10       GNU C Library: Shared libraries and Timezone
ii  libstdc++2.10- 2.95.4-7       The GNU stdc++ library