In order to research what caused the installation of a given package, I'd like to get a list of packages which depend on that package. I couldn't find anything obvious in
apt-cache rdepends packagename should do what you want
aptitude has a fairly nice way of handling this:
$ aptitude why bash i foomatic-filters PreDepends bash (>= 2.05)
By default, it only lists the "most installed, strongest, tightest, shortest" reason, but you can use
aptitude -v why to make it output everything it finds.
apt-cache showpkg <pkgname>
apt-cache showpkg lightdm
There is more than one way, with each method showing a different output.
For a detailed view of the full reverse dependency tree;
aptitude install apt-rdepends apt-rdepends -r bash
apt-cache showpkg bash
Or a concise list:
apt-cache rdepends bash
The simplest option is still:
apt rdepends package-name
which does not require you to install any package.
In addition to other good answers, an APT/APT-GET
-s does a "simulated" removal (or install).
sudo apt -s remove <pkgname>
--simulated to remove (or install) packages, will normally list any dependencies affected. It will show orphaned packages when removing, or needed dependencies when installing without actually executing the
remove. Informational only.