[SOLVED] I have a question about apt in mint

Hi everybody,

I've installed and uninstalled many packages in Mint for a long time, but I NEVER though about this situation.

If I uninstall a package, will it also uninstall it's dependencies as well? Thanks

Usually it will. If you want to cleanup all packages that are installed though they are no longer needed:
sudo apt-get autoremove

As far as I am aware, it will uninstall those dependencies if they are no longer needed by other packages.

This will help

https://askubuntu.com/a/151943

It depends how the dependencies were installed. If you installed them explicitly (including via a distro installation script), they will remain. If they came over as dependencies, they will be removed.

Originally Posted by j-ray Usually it will. If you want to cleanup all packages that are installed though they are no longer needed: sudo apt-get autoremove

Originally Posted by Lysander666 As far as I am aware, it will uninstall those dependencies if they are no longer needed by other packages. This will help https://askubuntu.com/a/151943

Originally Posted by hazel It depends how the dependencies were installed. If you installed them explicitly (including via a distro installation script), they will remain. If they came over as dependencies, they will be removed.

Thanks to all for the replies and links

Looking at the answers, I think that the word 'dependency' is somewhat ambiguous.

Example: package xyz needs package abc. Then
apt install xyz
will also install abc (of course!)

Uninstalling xyz:
apt remove xyz
will not remove abc, but you can remove it with
apt autoremove (as stated before)
or
apt remove abc
If you want abc to remain:
apt install abc

Uninstalling abc:
apt remove abc
will also remove xyz, logical because xyz cannot function without abc.
You get the change to answer no, if you want xyz to remain.

Yes, and no.

When you remove/purge a package, all those packages which were automatically installed as dependencies of that package, if they are no longer also dependencies of other packages, will be placed in a list of "packages to be autoremoved" which you can remove with sudo apt autoremove.

However, the package manager is cautious. When a package is uninstalled, any "unused dependencies" of that package which are recommended packages of other still-installed packages will not be added to the autoremove list.

This is my experience anyway, and leads to the occasional behaviour where, in a system where APT is not configured to install both dependencies and recommended packages for a given package, you install a package and it pulls in dependencies, only to uninstall it later and find that not all those dependencies are added to the autoremove list.

But if you use synaptic rather than apt, the left-over dependencies are removed. A lot of people get themselves into a bind as follows:

1) Install a particular desktop. These desktops are "metapackages", empty packages that bring over a load of applications and libraries as dependencies.
2) Try to get rid of an application you don't want. You get a huge list of other packages that will disappear along with it, including a lot of stuff that you actually want to keep.

What has happened? The application you want to remove is a dependency of the desktop package, so that will be removed too. But all the rest of the desktop apps came onto your machine as dependencies of the desktop, so they are also marked for removal.

At this point you have a choice. Either you abort the whole thing, or you must make a list on paper of the apps you want to keep and reinstall them explicitly.