How do I get a list of obsolete packages?

Question

I'm trying to figure out a way to get a list of the packages that are no longer available in the repositories that I have enabled. This workstation has been through quite a few versions of Ubuntu and has had many 3rd party repositories added and removed. I'd like to get a list of software that I have from these removed repositories, so I can clean it up or add back the appropriate repositories.

Answer 1

aptitude search '~o'

Aptitude has some very powerful searching available. Unfortunately the syntax is a bit unwieldy and you have to dig past the manpage to find the documentation, but its worth it.

apt-show-versions can also be helpful:

apt-show-versions | grep 'No available version'

Answer 2

I would not try any of both advices here. As far as I know there is a slight difference in meaning between "no available version" "not installed" and, what the question is about, "obsolete".

For example: a package compiled from source will be happily indicated as "no available version" or even "not installed" depending on if there's a PPA available.

But of course this doesn't necessarily mean that the package is "obsolete".

FYI: even aptitude makes this mistake. Determining if something is obsolete still remains a matter of knowing what you're doing.

Answer 3

There may be a cleaner way, but off the top of my head you can do

dpkg -l | cut -f 3 -d ' ' > installed
xargs -n 1 --replace=X apt-cache search ^X$ < installed | cut -f 1 -d ' ' > available
diff installed available

Cleanup the first few lines of the installed file: it will have headers.

Bonus if anyone can fix my syntax highlighting...