Re: [Aptitude-devel] aptitude ~A question

[David Wright <deblis@lionunicorn.co.uk>]

On Sun 06 Nov 2016 at 08:18:52 (+0100), Steve wrote:
> Hi Sven and Axel,
> 
> Thank you for your explanation, I understand a bit better the logic. But
> there is still something that doesn't quite match. Please consider the
> following.
> 
> apt-cache policy | grep 'a='
>     release a=now
>     release v=14.04,o=LP-PPA-opencpn-opencpn,a=trusty,n=trusty,l=OpenCPN,c=main
>     release o=Debian Mozilla Team,a=jessie-backports,n=jessie-backports,l=Debian Mozilla Team,c=firefox-release
>     release v=8.6,o=Unofficial Multimedia Packages,a=stable,n=jessie,l=Unofficial Multimedia Packages,c=non-free
>     release v=8.6,o=Unofficial Multimedia Packages,a=stable,n=jessie,l=Unofficial Multimedia Packages,c=main
>     release o=Debian Backports,a=jessie-backports,n=jessie-backports,l=Debian Backports,c=contrib
>     release o=Debian Backports,a=jessie-backports,n=jessie-backports,l=Debian Backports,c=main
>     release v=8,o=Debian,a=stable,n=jessie,l=Debian-Security,c=non-free
>     release v=8,o=Debian,a=stable,n=jessie,l=Debian-Security,c=contrib
>     release v=8,o=Debian,a=stable,n=jessie,l=Debian-Security,c=main
>     release v=8.6,o=Debian,a=stable,n=jessie,l=Debian,c=contrib
>     release v=8.6,o=Debian,a=stable,n=jessie,l=Debian,c=non-free
>     release v=8.6,o=Debian,a=stable,n=jessie,l=Debian,c=main
> 
> 
> Now let's plug the value of a in 'aptitude search ~A$a~i | wc -l':
> 
> 
> a=              aptitude search ~A[$a]~i | wc -l 					dpkg -l | grep ^ii | wc -l
> trusty                                    16
> jessie$                                    0
> jessie-backports                         248
> stable                                  3243
> TOTAL                                   3507                3349
> now                                     3349                3349
> 
> 
> so 3507 ≠ 3349. Both figures should be equal as I understand. It seems
> that some packages are counted two or more times or my calculation is
> plain wrong.
> 
> Thoughts?

Piping to wc -l throws most of the information away.
Redirect the output to files instead, thus:

search jessie > /tmp/jessie
... repeated for others ...
search total | sort > /tmp/total

Now:

cat /tmp/jessie /tmp/all-the-others | sort | diff -u - /tmp/total | less -S

and see exactly what's going on. The lines starting with "-" are the
ones which are in the concatenation of files but not in the total file.
Vice versa for "+".

Cheers,
David.