Pacman

pacman is the package manager used by the Arch Linux distribution. It tracks all the software installed in the system and can automatically install, uninstall, upgrade or downgrade packages using a remote central repository or local .pkg.tar.xz files.

Usage

pacman is very simple to use.

# pacman -S package1 package2 ...

Uninstalling

To uninstall a package or group of packages, simply pass its name as argument to the -R option:

# pacman -R package or group

System upgrade

To upgrade the whole system, issue the following command:

# pacman -Syu

Partial upgrades are not supported in Arch Linux. Always upgrade the whole system at once and bring it to the latest version, otherwise incompatibilities could occur.

Package databases

You can query the package database of the remote repositories or the local database of installed packages using the -S or the -Q options respectively. The lower-case suboptions determine which operation will be done.

Searching for packages

For online repositories:

# pacman -Ss packages

For local packages:

# pacman -Qs packages

Both the names and the descriptions of packages will be searched.

Obtaining information on a package

For online repositories:

# pacman -Si package

For local packages:

# pacman -Qi package

Files belonging to a package

To obtain a list of files that belong to an installed package:

# pacman -Ql package

Which package owns a file

To find out which installed package owns any given file:

# pacman -Qo /path/to/file

Unneeded packages

To list packages that were installed as dependencies and that are not needed anymore:

# pacman -Qdt