Using -fetch, -install, -setup, -get, -uninstall and -remove

The most basic operations of "getting" and removing packages is often all you need to know about Pacman to get software that you are interested in. Sometimes, however, it helps to have finer controls over these operations. This is provided by

-fetch. This fetches Pacman information from remote caches and resolves any dependencies and evaluates whether the packages can be installed on your system. The advantage of first doing -fetch is that if there are several problems preventing a complicated installation, you can see all of the problems before having to repeatedly attempt to do the installation.
-install. The -install switch has the same effect as -fetch but then also attempts to install the packages that you have indicated on the command line. If the installation fails, the reasons for the failure will be displayed on the command line.
-setup. The -setup switch produces a combined environment using all of the software in your installation. If this is consistent, it produces scripts setup.csh, setup.sh and setup.py which set up a user to use all of the software installed in the installation.

Let's try this now. For example, make a new work area and try

% pacman -fetch BU:nEdit Pacman:Pacman
% pacman -l
[ ] nEdit, in cache [/home/youssef/Pacman/work]
[ ] Pacman, in cache [/home/youssef/Pacman/work]

this tells you that all dependencies have been resolved and that you may be able to do the installation. To install the packages, you can do % pacman -install BU:nEdit Pacman:Pacman or simply

% pacman -install

to install all of the top level packages in the installation. You will then see

% pacman -l
[*] nEdit, in cache [/home/youssef/Pacman/work]
[*] Pacman, in cache [/home/youssef/Pacman/work]

that the installation has worked but no setup scripts have appeared. Finally, do

% pacman -setup

and you will see that the setup scripts appear. To avoid confusion, -setup always applies to an entire installation, so if you see setup scripts, it automatically means that Pacman has concluded that all of the software in the installation has successfully installed and that the packages are consistent.

Part of the point of separating -setup is to allow installations that contain inconsistent packages. This is useful, for example, if you want to have a single installation that contains multiple incompatible versions of the same package. See the versions section for of the documentation for more details about this.

-get is the same as -fetch followed by -install and -setup.
-uninstall lets you uninstall individual packages without removing them from the local installation.
-remove lets you remove the indicated list of packages from an installation entirely.
-remove-all lets you remove all packages in an installation.

For practice, try -uninstall on various package in your installation and then do % pacman -install or % pacman -get to re-install.

Using -fetch, -install, -setup, -get, -uninstall and -remove

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