How To: APT guide

2 minute read

Apt is the debian tool to install, remove and search packages. It is a front-end to the dpkg package manager and offer easy searching, installing …, by using apt-get and apt-cache.

This Howto will give you the basic commands you need to know for installing, removing, searching package and so on.

1. Searching for packages: apt-cache

Let say, I’m looking for xmms plugins, the tool for searching is apt-cache.

apt-cache search xmms plugin

This will output a list of packages and their short description which are related to your search.

2. Getting more Information about a package: apt-cache

You can obtain detailled information about a package, such as the version, the maintainer name, the size occupied by the package once it will be installed and a longer description:

apt-cache show package1 package2 ...

3. Installing a package: apt-get install

Once you pointed out a package you want to install, you need to type:

sudo apt-get install xmms-status-plugin

You might need to install several package at the same time, in that case simply add any other package one after the other one, separated by a “ “ (Space).

sudo apt-get install package1 package2 ...

apt-get automatically deals with dependencies, therefore any required package will be installed.

If the package you want to install is already install, you can force the reinstallation by using the --reinstall switch.

sudo apt-get install xmms-status-plugin --reinstall

4. Removing packages: apt-get remove

There is 2 ways of removing a package:

  1. remove the binaries, doc,…
  2. remove the binaries as well as the configuration file.

For a simple removing type:

sudo apt-get remove package1 package2

For a complete remove:

shell sudo apt-get remove package1 package2 --purge `

5. Update your package database: apt-get update

You basically need to update your package manager anytime you want to install new package. Revision, Releases might have changed…

Running:

sudo apt-get update

will update the software database but will not upgrade your system.

6. Upgrading your system: apt-get [dist-]upgrade

In order to turn you system up-to-date with the latest softwares, you need to upgrade your system.

There is 2 different upgrade available: a simple upgrade and a smart upgrade. The smart approach also handle changing dependencies.

The first call is achieved with:

sudo apt-get upgrade

The smart upgrade with:

sudo apt-get dist-upgrade

7. Resolving conflicts and Broken packages: apt-get

Some installation, upgrade might sometime turn wrong. Most of the time a call to:

sudo apt-get -f install

will attempt to correct a system with broken dependencies.

8. Checking for dependencies and reverse dependencies: apt-cache

You can get the list of packages a given package depends on:

apt-cache depends package1 package2

as well as a list of packages depending on a given package:

apt-cache rdepends package1 package2

this is called reverse dependencies.