pacman/Tips and tricks

You may want to get the list of installed packages with their version, which is useful when reporting bugs or discussing installed packages.

• List all explicitly installed packages: pacman -Qe.
• List all packages in the package group named group: pacman -Sg group
• List all foreign packages (typically manually downloaded and installed or packages removed from the repositories): pacman -Qm.
• List all native packages (installed from the sync database): .
• List all explicitly installed native packages (i.e. present in the sync database) that are not direct or optional dependencies: .
• List packages by regex: .
• List packages by regex with custom output format (needs ): expac -s "%-30n %v" regex.

Figuring out which packages are largest can be useful when trying to free space on your hard drive. There are two options here: get the size of individual packages, or get the size of packages and their dependencies.

The following command will list all installed packages and their individual sizes:

$ LC_ALL=C pacman -Qi | awk '/^Name/{name=$3} /^Installed Size/{print $4$5, name}' | sort -h

To list package sizes with their dependencies,

• Install and run .
• Run with the option.

To list the download size of several packages (leave packages blank to list all packages):

$ expac -S -H M '%k\t%n' packages

To list explicitly installed packages not in the meta package nor package group with size and description:

$ expac -H M "%011m\t%-20n\t%10d" $(comm -23 <(pacman -Qqen | sort) <({ pacman -Qqg base-devel; expac -l '\n' '%E' base; } | sort -u)) | sort -n

To list the packages marked for upgrade with their download size

$ expac -S -H M '%k\t%n' $(pacman -Qqu) | sort -sh

To list the 20 last installed packages with , run:

$ expac --timefmt='%Y-%m-%d %T' '%l\t%n' | sort | tail -n 20

or, with seconds since the epoch (1970-01-01 UTC):

$ expac --timefmt=%s '%l\t%n' | sort -n | tail -n 20

List explicitly installed packages not in the meta package:

$ comm -23 <(pacman -Qqe | sort) <(expac -l '\n' '%E' base | sort)

List explicitly installed packages not in the meta package or package group:

$ comm -23 <(pacman -Qqe | sort) <({ pacman -Qqg base-devel; expac -l '\n' '%E' base; } | sort -u)

List all installed packages unrequired by other packages, and which are not in the meta package or package group:

$ comm -23 <(pacman -Qqt | sort) <({ pacman -Qqg base-devel; echo base; } | sort -u)

As above, but with descriptions:

$ expac -H M '%-20n\t%10d' $(comm -23 <(pacman -Qqt | sort) <({ pacman -Qqg base-devel; echo base; } | sort -u))

List all installed packages that are not in the specified repository repo_name

$ comm -23 <(pacman -Qq | sort) <(pacman -Sql repo_name | sort)

List all installed packages that are in the repo_name repository:

$ comm -12 <(pacman -Qq | sort) <(pacman -Sql repo_name | sort)

List all packages on the Arch Linux ISO that are not in the meta package:

$ comm -23 <(curl https://gitlab.archlinux.org/archlinux/archiso/-/raw/master/configs/releng/packages.x86_64) <(expac -l '\n' '%E' base | sort)

To list all development/unstable packages, run:

$ pacman -Qq | grep -Ee '-(bzr|cvs|darcs|git|hg|svn)

To download packages, or groups of packages:

# cd ~/Packages
# pacman -Syw --cachedir . base base-devel grub-bios xorg gimp
# repo-add ./custom.db.tar.gz ./*

Pacman, which will reference the host installation by default, will not properly resolve and download existing dependencies. In cases where all packages and dependencies are wanted, it is recommended to create a temporary blank DB and reference it with :

# mkdir /tmp/blankdb
# pacman -Syw --cachedir . --dbpath /tmp/blankdb base base-devel grub-bios xorg gimp
# repo-add ./custom.db.tar.gz ./*

Then you can burn the "Packages" folder to a CD/DVD or transfer it to a USB stick, external HDD, etc.

To install:

1. Mount the media:

# mkdir /mnt/repo
# mount /dev/sr0 /mnt/repo    #For a CD/DVD.
# mount /dev/sdxY /mnt/repo   #For a USB stick.

2. Edit and add this repository before the other ones (e.g. extra, core, etc.). This is important. Do not just uncomment the one on the bottom. This way it ensures that the files from the CD/DVD/USB take precedence over those in the standard repositories:

3. Finally, synchronize the pacman database to be able to use the new repository:

# pacman -Syu

Use the repo-add script included with pacman to generate a database for a personal repository. Use repo-add --help for more details on its usage. A package database is a tar file, optionally compressed. Valid extensions are .db or .files followed by an archive extension of .tar, .tar.gz, .tar.bz2, .tar.xz, .tar.zst, or .tar.Z. The file does not need to exist, but all parent directories must exist.

To add a new package to the database, or to replace the old version of an existing package in the database, run:

$ repo-add /path/to/repo.db.tar.gz /path/to/package-1.0-1-x86_64.pkg.tar.xz

The database and the packages do not need to be in the same directory when using repo-add, but keep in mind that when using pacman with that database, they should be together. Storing all the built packages to be included in the repository in one directory also allows to use shell glob expansion to add or update multiple packages at once:

$ repo-add /path/to/repo.db.tar.gz /path/to/*.pkg.tar.xz

If you are looking to support multiple architectures then precautions should be taken to prevent errors from occurring. Each architecture should have its own directory tree:

The repo-add executable checks if the package is appropriate. If this is not the case you will be running into error messages similar to this:

==> ERROR: '/home/archie/customrepo/arch/foo-arch.pkg.tar.xz' does not have a valid database archive extension.

repo-remove is used to remove packages from the package database, except that only package names are specified on the command line.

$ repo-remove /path/to/repo.db.tar.gz pkgname

Once the local repository database has been created, add the repository to for each system that is to use the repository. An example of a custom repository is in . The repository's name is the database filename with the file extension omitted. In the case of the example above the repository's name would simply be repo. Reference the repository's location using a URL, or via FTP using ftp://localhost/path/to/directory.

If willing, add the custom repository to the list of unofficial user repositories, so that the community can benefit from it.

If you happen to run several Arch boxes on your LAN, you can share packages so that you can greatly decrease your download times. Keep in mind you should not share between different architectures (i.e. i686 and x86_64) or you will run into problems.

If you are looking for a quick solution, you can simply run a basic temporary webserver which other computers can use as their first mirror.

First of all, make pacman databases available into the folder you will serve:

# ln -s /var/lib/pacman/sync/*.db /var/cache/pacman/pkg/

Then start serving this folder. For example, with Python http.server module:

$ python -m http.server -d /var/cache/pacman/pkg/

$ python -m http.server -d /var/cache/pacman/pkg/ 8080

Then edit on each client machine to add this server as the top entry:

If looking for a more standalone solution, offers a very minimal webserver. Replace the previous command with e.g.:

$ sudo -u http darkhttpd /var/cache/pacman/pkg --no-server-id

You could also run darkhttpd as a systemd service for convenience: see Systemd#Writing unit files.

, a web small server written in Rust, can also be used:

$ miniserve /var/cache/pacman/pkg

Then edit as above with the first url miniserve is available at.

If you are already running a web server for some other purpose, you might wish to reuse that as your local repository server instead. For example, if you already serve a site with nginx, you can add an nginx server block listening on port 8080:

/etc/nginx/nginx.conf

server {
    listen 8080;
    root /var/cache/pacman/pkg;
    server_name myarchrepo.localdomain;
    try_files $uri $uri/;
}

Remember to restart after making this change.

It is possible to use one machine on a local network as a read-only package cache by overlay mounting its directory. Such a configuration is advantageous if this server has installed on it a reasonably comprehensive selection of up-to-date packages which are also used by other boxes. This is useful for maintaining a number of machines at the end of a low bandwidth upstream connection.

As an example, to use this method:

# mkdir /tmp/remote_pkg /mnt/workdir_pkg /tmp/pacman_pkg
# sshfs remote_username@remote_pkgcache_addr:/var/cache/pacman/pkg /tmp/remote_pkg -C
# mount -t overlay overlay -o redirect_dir=off -o index=off -o metacopy=off -o lowerdir=/tmp/remote_pkg,upperdir=/var/cache/pacman/pkg,workdir=/mnt/workdir_pkg /tmp/pacman_pkg

After this, run pacman using the option , e.g.:

# pacman -Syu --cachedir /tmp/pacman_pkg

There are Arch-specific tools for automatically discovering other computers on your network offering a package cache. Try pacredir, pacserve, , or . pkgdistcache uses Avahi instead of plain UDP which may work better in certain home networks that route instead of bridge between WiFi and Ethernet.

Historically, there was PkgD and multipkg, but they are no longer maintained.

In order to share packages between multiple computers, simply share using any network-based mount protocol. This section shows how to use SSHFS to share a package cache plus the related library-directories between multiple computers on the same local network. Keep in mind that a network shared cache can be slow depending on the file-system choice, among other factors.

First, install any network-supporting filesystem packages: , curlftpfs, or .

Then, to share the actual packages, mount from the server to on every client machine.

Another approach in a local environment is rsync. Choose a server for caching and enable the rsync daemon. On clients synchronize two-way with this share via the rsync protocol. Filenames that contain colons are no problem for the rsync protocol.

Draft example for a client, using within the share name ensures an architecture-dependent sync:

 # rsync rsync://server/share_$(uname -m)/ /var/cache/pacman/pkg/ ...
 # pacman ...
 # paccache ...
 # rsync /var/cache/pacman/pkg/ rsync://server/share_$(uname -m)/  ...

nginx can be used to proxy package requests to official upstream mirrors and cache the results to the local disk. All subsequent requests for that package will be served directly from the local cache, minimizing the amount of internet traffic needed to update a large number of computers.

In this example, the cache server will run at http://cache.domain.example:8080/ and store the packages in .

Install nginx on the computer that is going to host the cache. Create the directory for the cache and adjust the permissions so nginx can write files to it:

# mkdir /srv/http/pacman-cache
# chown http:http /srv/http/pacman-cache

Use the nginx pacman cache config as a starting point for . Check that the directive works for your needs. In the upstream server blocks, configure the directives with addresses of official mirrors, see examples in the configuration file about the expected format. Once you are satisfied with the configuration file start and enable nginx.

In order to use the cache each Arch Linux computer (including the one hosting the cache) must have the following line at the top of the mirrorlist file:

Pacoloco is an easy-to-use proxy cache server for pacman repositories. It also allows automatic prefetching of the cached packages.

It can be installed as . Open the configuration file and add pacman mirrors:

Restart and the proxy repository will be available at http://myserver:9129/repo/mycopy.

Flexo is yet another proxy cache server for pacman repositories. Flexo is available as . Once installed, start the unit.

Flexo runs on port by default. Enter to the top of your so that pacman downloads packages via Flexo.

Use Syncthing or Resilio Sync to synchronize the pacman cache folders (i.e. ).

By default, removes package tarballs from the cache that correspond to packages that are not installed on the machine the command was issued on. Because pacman cannot predict what packages are installed on all machines that share the cache, it will end up deleting files that should not be.

To clean up the cache so that only outdated tarballs are deleted, add this entry in the section of /etc/pacman.conf:

CleanMethod = KeepCurrent

To recreate a package from the file system, use . Files from the system are taken as they are, hence any modifications will be present in the assembled package. Distributing the recreated package is therefore discouraged; see ABS and Arch Linux Archive for alternatives.

Keeping a list of all explicitly installed packages can be useful to backup a system or quicken the installation of a new one:

$ pacman -Qqe > pkglist.txt

To keep an up-to-date list of explicitly installed packages (e.g. in combination with a versioned /etc/), you can set up a hook. Example:

[Trigger]
Operation = Install
Operation = Remove
Type = Package
Target = *

[Action]
When = PostTransaction
Exec = /bin/sh -c '/usr/bin/pacman -Qqe > /etc/pkglist.txt'

To install packages from a previously saved list of packages, while not reinstalling previously installed packages that are already up-to-date, run:

# pacman -S --needed - < pkglist.txt

However, it is likely foreign packages such as from the AUR or installed locally are present in the list. To filter out from the list the foreign packages, the previous command line can be enriched as follows:

# pacman -S --needed $(comm -12 <(pacman -Slq | sort) <(sort pkglist.txt))

Eventually, to make sure the installed packages of your system match the list and remove all the packages that are not mentioned in it:

# pacman -Rsu $(comm -23 <(pacman -Qq | sort) <(sort pkglist.txt))

If you are suspecting file corruption (e.g. by software/hardware failure), but are unsure if files were corrupted, you might want to compare with the hash sums in the packages. This can be done with :

# paccheck --md5sum --quiet

For recovery of the database see #Restore pacman's local database. The files can also be extracted as from the respective package files.

To reinstall all native packages, use:

# pacman -Qqn | pacman -S -

Foreign (AUR) packages must be reinstalled separately; you can list them with .

Pacman preserves the installation reason by default.

See pacman/Restore local database.

If you have Arch installed on a USB key and manage to mess it up (e.g. removing it while it is still being written to), then it is possible to re-install all the packages and hopefully get it back up and working again (assuming USB key is mounted in )

# pacman -S $(pacman -Qq --dbpath /newarch/var/lib/pacman) --root /newarch --dbpath /newarch/var/lib/pacman

For example, if you want to see the contents of supplied within the package:

$ bsdtar -xOf /var/cache/pacman/pkg/systemd-204-3-x86_64.pkg.tar.xz etc/systemd/logind.conf

Or you can use to browse the archive:

$ vim /var/cache/pacman/pkg/systemd-204-3-x86_64.pkg.tar.xz

Already running processes do not automatically notice changes caused by updates. Instead, they continue using old library versions. That may be undesirable, due to potential issues related to security vulnerabilities or other bugs, and version incompatibility.

Processes depending on updated libraries may be found using either htop, which highlights the names of the affected programs, or with a snippet based on , which also prints the names of the libraries:

# lsof +c 0 | grep -w DEL | awk '1 { print $1 ": " $NF }' | sort -u

This solution will only detect files, that are normally kept opened by running processes, which basically limits it to shared libraries ( files). It may miss some dependencies, like those of Java or Python applications.

Many packages attempt to install documentation and translations in several languages. Some programs are designed to remove such unnecessary files, such as , which runs after a package is installed to delete the unneeded locale files. A more direct approach is provided through the directive in , which prevent these files from ever being installed.

The example below installs English (US) files, or none at all:

/etc/pacman.conf

NoExtract = usr/share/help/* !usr/share/help/C/*
NoExtract = usr/share/gtk-doc/html/*
NoExtract = usr/share/locale/* usr/share/X11/locale/*/* usr/share/i18n/locales/* opt/google/chrome/locales/* !usr/share/X11/locale/C/*
NoExtract = !*locale*/en*/* !usr/share/*locale*/locale.*
NoExtract = !usr/share/*locales/en_?? !usr/share/*locales/i18n* !usr/share/*locales/iso*
NoExtract = usr/share/i18n/charmaps/* !usr/share/i18n/charmaps/UTF-8.gz
NoExtract = !usr/share/*locales/trans*
NoExtract = usr/share/man/* !usr/share/man/man*
NoExtract = usr/share/vim/vim*/lang/*
NoExtract = usr/lib/libreoffice/help/en-US/*
NoExtract = usr/share/kbd/locale/*
NoExtract = usr/share/*/translations/*.qm usr/share/*/nls/*.qm usr/share/qt/translations/*.pak !*/en-US.pak # Qt apps
NoExtract = usr/share/*/locales/*.pak opt/*/locales/*.pak usr/lib/*/locales/*.pak !*/en-US.pak # Electron apps
NoExtract = opt/onlyoffice/desktopeditors/dictionaries/* !opt/onlyoffice/desktopeditors/dictionaries/en_US/*
NoExtract = opt/onlyoffice/desktopeditors/editors/web-apps/apps/*/main/locale/* !*/en.json
NoExtract = opt/onlyoffice/desktopeditors/editors/web-apps/apps/*/main/resources/help/* !*/help/en/*
NoExtract = opt/onlyoffice/desktopeditors/converter/empty/*/*
NoExtract = usr/share/ibus/dicts/emoji-*.dict !usr/share/ibus/dicts/emoji-en.dict

When trying to install a package from a bad connection (e.g. a train using a cell phone), use the option to lessen the chance of receiving errors such as:

error: failed retrieving file […] Operation too slow. Less than 1 bytes/sec transferred the last 10 seconds

or

error: failed retrieving file […] Operation timed out after 10014 milliseconds with 0 out of 0 bytes received

When downloading packages pacman uses the mirrors in the order they are in . The mirror which is at the top of the list by default however may not be the fastest for you. To select a faster mirror, see Mirrors.

Pacman's speed in downloading packages can also be improved by using a different application to download packages, instead of pacman's built-in file downloader, or by enabling parallel downloads.

In all cases, make sure you have the latest pacman before doing any modifications.

# pacman -Syu

Powerpill is a pacman wrapper that uses parallel and segmented downloading to try to speed up downloads for pacman.

This is also very handy if you need more powerful proxy settings than pacman's built-in capabilities.

To use , first install the package then modify /etc/pacman.conf by uncommenting the following line in the section:

XferCommand = /usr/bin/wget --passive-ftp --show-progress -c -q -N %u

Instead of uncommenting the parameters in /etc/pacman.conf, you can also modify the configuration file directly (the system-wide file is , per user files are $HOME/.wgetrc).

aria2 is a lightweight download utility with support for resumable and segmented HTTP/HTTPS and FTP downloads. aria2 allows for multiple and simultaneous HTTP/HTTPS and FTP connections to an Arch mirror, which should result in an increase in download speeds for both file and package retrieval.

Install , then edit /etc/pacman.conf by adding the following line to the section:

XferCommand = /usr/bin/aria2c --allow-overwrite=true --continue=true --file-allocation=none --log-level=error --max-tries=2 --max-connection-per-server=2 --max-file-not-found=5 --min-split-size=5M --no-conf --remote-time=true --summary-interval=60 --timeout=5 --dir=/ --out %o %u

See for used aria2c options.

• : The directory to store the downloaded file(s) as specified by pacman.
• : The output file name(s) of the downloaded file(s).
• %o: Variable which represents the local filename(s) as specified by pacman.
• : Variable which represents the download URL as specified by pacman.

There are other downloading applications that you can use with pacman. Here they are, and their associated XferCommand settings:

• :
• : XferCommand = /usr/bin/lftp -c pget %u
• :
• : (please read the documentation on the Github project page for more info)
• : (please read the documentation on the project page for more info)

• Apper — Qt 5 application and package manager using PackageKit written in C++. Supports AppStream metadata.

https://userbase.kde.org/Apper || apper