Pacman - The Arch package manager

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I use GNU/Linux. It’s pretty good. One of the things I really like about NIX based operating systems is the ability for you to manage all your packages from the command line. I can attest that this is the best way to manage your packages. There are many package managers out there for all the various distributions of Linux. I happen to use Arch Linux, a rather minimal version of linux. Almost all of the packages you need, need to be installed by the user. Arch based systems use the pacman package manager. So how do use it effectively? My honest opinion is to run the following command in your terminal:

man pacman

Honestly, just read it. But if you can’t make head or tail out of the man page, here are some of the commands that you should know how to use. First, the command to install packages:

pacman -S [package_name]

Now, if you want to search for a package in the official Arch package repositories, this is the command used to query the database:

pacman -Ss [query]

So, that covers the basics of installing packages. Now for maintenance. This is the command used to upgrade all installed packages:

pacman -Syu [query]

You will use that command the most. Now this command is useful, but rarely used:

pacman -Rns $(pacman -Qtdq)

That one requires a bit of explanation. Basically, this one line does two things. First, it generates a list of all the unused packages and their orphans with pacman -Qtdq. It passes the list to pacman -Rns which then removes them as well as the configuration files generated by it. If you have always uninstalled packages cleanly, this command should return a No arguments passed error. If however, you have done some messy uninstalls, this one-liner gets rid of the stuff you don’t use and won’t need.

Now for removing packages. This should be the only command that you use:

pacman -Rns

It removes the package, the dependencies that were installed for it that are not dependencies for other packages, and all the configuration files that were produced. It basically reverts you to the state your machine was in during pre-install.

This is something that always infuriated me about Windows. When you tried to uninstall something, the program may have gone, but if you happen to browse the program files later on, you would find the remains of them lodged somewhere.No clean uninstalls. Linux package managers do a much better job of this.

Now what if you want some specific information regarding packages that you have already installed? There are ways to get what you want. Say you want to list all the packages installed on your system. Simply run the following command:

pacman -Q

This will literally list out all the packages that are installed on your system. If you want to know how many you have in total, run the following command:

pacman -Q | wc -l

Which should give you the right number. But this shows everything. All the dependencies. Packages that were a part of the base group and the base-devel group. So more useful command to that can be used to see the packages that you have explicitly installed is the following:

pacman -Qte

And you can pipe that into wc -l again to get the number.

Now say you want to find where a certain package has installed its files. This happens sometimes. I used it recently when I wanted to install zsh-autosuggestions and could not find the file that I wanted to source from my .zshrc. Run the following command:

pacman -Ql [package_name]

If you run the above command without specifying a package, Pacman will list out all the package files of all the packages installed on your system. Its a long list.

And that should cover the basics.