Why does installing python-minimal package also grab the python package on Debian?

Question

From running:

apt-cache depends python2.6-minimal | grep Depends

and

apt-cache depends python2.6 | grep Depends

it looks like python2.6 depends on python2.6-minimal and a lot more.

However, when I run, apt-get install python2.6-minimal it tries to install the same packages as when I run apt-get install python2.6 -- both warns 17.0 MB of additional disk space will be used. Why is this happening?

P.S.

Another funky thing that seems to happen is that when I try to install the python package, it wants 18.0 MB of additional disk space. But

apt-cache depends python | grep Depends

only shows

Depends: python2.6
Depends: python-minimal

Why does python require a megabyte more than python2.6?

Solution 1

The reason you are having extra package installations, is because of python-minimal's recommends. apt-get has been configured to automatically install all recommended packages, when you install a new package. You can tell apt-get to not install recommended packages like this.

apt-get install --no-install-recommends python2.6-minimal

Just remember... When you don't install recommends, you might not get all the functionality. Often people assume you always install recommends, then they have no idea why some installed package throws errors. The problem is most recommends should really be suggests, which has made recommends somewhat useless. Most of the time I install without recommends, and it only results in unexpected behavior occasionally. Any package that is not system or desktop critical, usually can be installed without recommends.

I hope I was able to help,

Solution 2

python-minimal recommends python.

% apt-cache depends python-minimal
python-minimal
  Depends: python2.7-minimal
  Depends: dpkg
    dpkg:i386
  Recommends: python
  Conflicts: python-central
  Conflicts: <python-central:i386>
  Breaks: idle
...

By default, apt-get installs recommendations automatically. Try

sudo apt-get install --no-install-recommends python-minimal

Solution 3

As well as the other suggestions, you can also disable automatic bundling of recommends globally by adding a file in /etc/apt/apt.conf.d with the statement APT::Install-Recommends "0";.