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