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# pacman/Tips and tricks

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< Pacman

Related articles

- Mirrors
- Creating packages

For general methods to improve the flexibility of the provided tips or pacman itself, see Core utilities and Bash.

## Maintenance

This article or section needs expansion.

Reason: `Usage=` introduced with pacman 4.2, see [1] (Discuss in Talk:Pacman/Tips and tricks)
Note: Instead of using comm (which requires sorted input with sort) in the sections below, you may also use `grep -Fxf` or `grep -Fxvf`.

See also System maintenance.

### Listing packages

#### With version

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(s)): `pacman -Qn`.
- List all explicitly installed native packages (i.e. present in the sync database) that are not direct or optional dependencies: `pacman -Qent`.
- List packages by regex: `pacman -Qs regex`.
- List packages by regex with custom output format (needs expac): `expac -s "%-30n %v" regex`.

#### With size

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.

##### Individual packages

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

##### Packages and dependencies

To list package sizes with their dependencies,

- Install expac and run `expac -H M '%m\t%n' | sort -h`.
- Run pacgraph with the `-c` 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 base nor package group base-devel 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 | uniq)) | sort -n

To list the packages marked for upgrade with their download size

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

#### By date

To list the 20 last installed packages with expac, 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

#### Not in a specified group, repository or meta package

Note: To get a list of packages installed as dependencies but no longer required by any installed package, see #Removing unused packages (orphans).

List explicitly installed packages not in the base meta package:

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

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

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

As above, but with descriptions:

    $ expac -H M '%-20n\t%10d' $(comm -23 <(pacman -Qqt | sort) <({ pacman -Qqg base-devel; expac -l '\n' '%E' 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 base meta package:

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

Tip: Alternatively, use `combine` (instead of `comm`) from the moreutils package which has a syntax that is easier to remember. See combine(1).

#### Development packages

To list all development/unstable packages, run:

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

### Browsing packages

To browse all installed packages with an instant preview of each package:

    $ pacman -Qq | fzf --preview 'pacman -Qil {}' --layout=reverse --bind 'enter:execute(pacman -Qil {} | less)'

This uses fzf to present a two-pane view listing all packages with package info shown on the right.

Enter letters to filter the list of packages; use arrow keys (or `Ctrl-j`/`Ctrl-k`) to navigate; press `Enter` to see package info under less.

To browse all packages currently known to pacman (both installed and not yet installed) in a similar way, using fzf, use:

    $ pacman -Slq | fzf --preview 'pacman -Si {}' --layout=reverse

The navigational keybindings are the same, although Enter will not work in the same way.

### Listing files owned by a package with size

This one might come in handy if you have found that a specific package uses a huge amount of space and you want to find out which files make up the most of that.

    $ pacman -Qlq package | grep -v '/$' | xargs -r du -h | sort -h

### Identify files not owned by any package

If your system has stray files not owned by any package (a common case if you do not use the package manager to install software), you may want to find such files in order to clean them up.

One method is to use `pacreport --unowned-files` as the root user from pacutils which will list unowned files among other details.

Another is to list all files of interest and check them against pacman:

    # find /etc /usr /opt | LC_ALL=C pacman -Qqo - 2>&1 >&- >/dev/null | cut -d ' ' -f 5-

Tip: The lostfiles script performs similar steps, but also includes an extensive blacklist to remove common false positives from the output.

### Tracking unowned files created by packages

Most systems will slowly collect several ghost files such as state files, logs, indexes, etc. through the course of usual operation.

`pacreport` from pacutils can be used to track these files and their associations via `/etc/pacreport.conf` (see pacreport(1) § FILES).

An example may look something like this (abridged):

    /etc/pacreport.conf

    [Options]
    IgnoreUnowned = usr/share/applications/mimeinfo.cache

    [PkgIgnoreUnowned]
    alsa-utils = var/lib/alsa/asound.state
    bluez = var/lib/bluetooth
    ca-certificates = etc/ca-certificates/trust-source/*
    dbus = var/lib/dbus/machine-id
    glibc = etc/ld.so.cache
    grub = boot/grub/*
    linux = boot/initramfs-linux.img
    pacman = var/lib/pacman/local
    update-mime-database = usr/share/mime/magic

Then, when using `pacreport --unowned-files` as the root user, any unowned files will be listed if the associated package is no longer installed (or if any new files have been created).

Additionally, aconfmgr (aconfmgr-gitAUR) allows tracking modified and orphaned files using a configuration script.

### Removing unused packages (orphans)

For recursively removing orphans and their configuration files:

    # pacman -Qtdq | pacman -Rns -

If no orphans were found, the output is `error: argument '-' specified with empty stdin`. This is expected as no arguments were passed to `pacman -Rns`.

Note: The arguments `-Qt` list only true orphans. To include packages which are optionally required by another package, pass the `-t` flag twice (i.e., `-Qtt`).

### Removing everything but essential packages

If it is ever necessary to remove all packages except the essentials packages, one method is to set the installation reason of the non-essential ones as dependency and then remove all unnecessary dependencies.

First, for all the packages installed "as explicitly", change their installation reason to "as dependency":

    # pacman -D --asdeps $(pacman -Qqe)

Then, change the installation reason to "as explicitly" of only the essential packages, those you do not want to remove, in order to avoid targeting them:

    # pacman -D --asexplicit base linux linux-firmware

Note:

- Additional packages can be added to the above command in order to avoid being removed. See Installation guide#Install essential packages for more info on other packages that may be necessary for a fully functional base system.
- This will also select the bootloader's package for removal. The system should still be bootable, but the boot parameters might not be changeable without it.

Finally, follow the instructions in #Removing unused packages (orphans) to remove all packages that have installation reason "as dependency".

### Getting the dependencies list of several packages

Dependencies are alphabetically sorted and doubles are removed.

Note: To only show the tree of local installed packages, use `pacman -Qi`.

    $ LC_ALL=C pacman -Si packages | awk -F'[:<=>]' '/^Depends/ {print $2}' | xargs -n1 | sort -u

Alternatively, with expac:

    $ expac -l '\n' %E -S packages | sort -u

### Listing changed backup files

The factual accuracy of this article or section is disputed.

Reason: What is the connection of this section to System backup? Listing modified "backup files" does not show files which are not tracked by pacman. (Discuss in Talk:Pacman/Tips and tricks#Warning about listing changed backup files)

If you want to back up your system configuration files, you could copy all files in `/etc/` but usually you are only interested in the files that you have changed. Modified backup files can be viewed with the following command:

    # pacman -Qii | awk '/^MODIFIED/ {print $2}'

Running this command with root permissions will ensure that files readable only by root (such as `/etc/sudoers`) are included in the output.

Tip: See #Listing all changed files from packages to list all changed files pacman knows about, not only backup files.

### Back up the pacman database

The following command can be used to back up the local pacman database:

    $ tar -cjf pacman_database.tar.bz2 /var/lib/pacman/local

Store the backup pacman database file on one or more offline media, such as a USB stick, external hard drive, or CD-R.

The database can be restored by moving the `pacman_database.tar.bz2` file into the `/` directory and executing the following command:

    # tar -xjvf pacman_database.tar.bz2

Note: If the pacman database files are corrupted, and there is no backup file available, there exists some hope of rebuilding the pacman database. Consult #Restore pacman's local database.
Tip: The pakbak-gitAUR package provides a script and a systemd service to automate the task. Configuration is possible in `/etc/pakbak.conf`.

### Check changelogs easily

When maintainers update packages, commits are often commented in a useful fashion. Users can quickly check these from the command line by installing pacologAUR. This utility lists recent commit messages for packages from the official repositories or the AUR, by using `pacolog <package>`.

## Installation and recovery

Alternative ways of getting and restoring packages.

### Installing packages from a CD/DVD or USB stick

This article or section is a candidate for merging with #Custom local repository.

Notes: Use as an example and avoid duplication (Discuss in Talk:Pacman/Tips and tricks)

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 `--dbpath`:

    # 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 `pacman.conf` 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:

    /etc/pacman.conf

    [custom]
    SigLevel = PackageRequired
    Server = file:///mnt/repo/Packages

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

    # pacman -Syu

### Custom local repository

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

Warning: repo-add adds the entries into the database in the same order as passed on the command line. If multiple versions of the same package are involved, care must be taken to ensure that the correct version is added last. In particular, note that lexical order used by the shell depends on the locale and differs from the vercmp(8) ordering used by pacman.

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:

    $ tree ~/customrepo/ | sed "s/$(uname -m)/<arch>/g"

    /home/archie/customrepo/
    └── <arch>
        ├── customrepo.db -> customrepo.db.tar.xz
        ├── customrepo.db.tar.xz
        ├── customrepo.files -> customrepo.files.tar.xz
        ├── customrepo.files.tar.xz
        └── personal-website-git-b99cce0-1-<arch>.pkg.tar.xz

    1 directory, 5 files

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 `pacman.conf` for each system that is to use the repository. An example of a custom repository is in `pacman.conf`. 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 `file://` 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.

### Network shared pacman cache

This article or section is a candidate for merging with Package_Proxy_Cache.

Notes: Same topic (Discuss in Talk:Pacman/Tips and tricks)

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.

#### Read-only cache

Note: If pacman fails to download 3 packages from the server, it will use another mirror instead. See https://bbs.archlinux.org/viewtopic.php?id=268066.

If you are looking for a quick solution, you can simply run a standalone webserver, e.g. darkhttpd, which other computers can use as a first mirror:

    # ln -s /var/lib/pacman/sync/*.db /var/cache/pacman/pkg
    $ sudo -u http darkhttpd /var/cache/pacman/pkg --no-server-id

You could also run darkhttpd as a systemd service for convenience. Just add this server at the top of your `/etc/pacman.d/mirrorlist` in client machines with `Server = http://mymirror:8080`. Make sure to keep your mirror updated.

If you are already running a web server for some other purpose, you might wish to reuse that as your local repository server instead of darkhttpd. 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 nginx after making this change.

Whichever web server you use, remember to open port 8080 to local traffic (and you probably want to deny anything not local). For example, if using iptables, add `-s 192.168.0.0/16 -p tcp --dport 8080 -j ACCEPT` to your ruleset (adjust for your LAN subnet if necessary).

#### Overlay mount of read-only cache

It is possible to use one machine on a local network as a read-only package cache by overlay mounting its `/var/cache/pacman/pkg` 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 lowerdir=/tmp/remote_pkg,upperdir=/var/cache/pacman/pkg,workdir=/mnt/workdir_pkg /tmp/pacman_pkg

Note concerning overlay: The working directory must be an empty directory on the same mounted device as the upper directory.

After this, run pacman using the option `--cachedir /tmp/pacman_pkg`, e.g.:

    # pacman -Syu --cachedir /tmp/pacman_pkg

#### Distributed read-only cache

There are Arch-specific tools for automatically discovering other computers on your network offering a package cache. Try pacredir, pacserve, pkgdistcacheAUR, or paclanAUR. 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.

#### Read-write cache

In order to share packages between multiple computers, simply share `/var/cache/pacman/` using any network-based mount protocol. This section shows how to use shfs or 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: shfs-utils, sshfs, curlftpfs, samba or nfs-utils.

Tip:

- To use sshfs or shfs, consider reading Using SSH Keys.
- By default, smbfs does not serve filenames that contain colons, which results in the client downloading the offending package afresh. To prevent this, use the `mapchars` mount option on the client.

Then, to share the actual packages, mount `/var/cache/pacman/pkg` from the server to `/var/cache/pacman/pkg` on every client machine.

Warning: Do not make `/var/cache/pacman/pkg` or any of its ancestors (e.g., `/var`) a symlink. Pacman expects these to be directories. When pacman re-installs or upgrades itself, it will remove the symlinks and create empty directories instead. However during the transaction pacman relies on some files residing there, hence breaking the update process. Refer to FS#50298 for further details.

#### two-way with rsync

Another approach in a local environment is rsync. Choose a server for caching and enable the Rsync#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 `uname -m` 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)/  ...

#### Dynamic reverse proxy cache using nginx

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 `/srv/http/pacman-cache/`.

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 `/etc/nginx/nginx.conf`. Check that the `resolver` directive works for your needs. In the upstream server blocks, configure the `proxy_pass` directives with addresses of official mirrors, see examples in the config 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:

    /etc/pacman.d/mirrorlist

    Server = http://cache.domain.example:8080/$repo/os/$arch
    ...

Note: You will need to create a method to clear old packages, as the cache directory will continue to grow over time. `paccache` (which is provided by pacman-contrib) can be used to automate this using retention criteria of your choosing. For example, `find /srv/http/pacman-cache/ -type d -exec paccache -v -r -k 2 -c {} \;` will keep the last 2 versions of packages in your cache directory.

#### Pacoloco proxy cache server

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 pacoloco. Open the configuration file and add pacman mirrors:

    /etc/pacoloco.yaml

    port: 9129
    repos:
      mycopy:
        urls:
          - http://mirror.lty.me/archlinux
          - http://mirrors.kernel.org/archlinux

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

#### Flexo proxy cache server

Flexo is yet another proxy cache server for pacman repositories. Flexo is available as flexo-gitAUR. Once installed, start the `flexo.service` unit.

Flexo runs on port `7878` by default. Enter `Server = http://myserver:7878/$repo/os/$arch` to the top of your `/etc/pacman.d/mirrorlist` so that pacman downloads packages via Flexo.

#### Synchronize pacman package cache using synchronization programs

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

#### Preventing unwanted cache purges

By default, `pacman -Sc` 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 `[options]` section of `/etc/pacman.conf`:

    CleanMethod = KeepCurrent

### Recreate a package from the file system

To recreate a package from the file system, use fakepkgAUR. 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.

### List of installed packages

Keeping a list of all the explicitly installed packages can be useful, to backup a system for example or speed up installation on a new system:

    $ pacman -Qqe > pkglist.txt

Note:

- With option `-t`, the packages already required by other explicitly installed packages are not mentioned. If reinstalling from this list they will be installed but as dependencies only.
- With option `-n`, foreign packages (e.g. from AUR) would be omitted from the list.
- Use `comm -13 <(pacman -Qqdt | sort) <(pacman -Qqdtt | sort) > optdeplist.txt` to also create a list of the installed optional dependencies which can be reinstalled with `--asdeps`.
- Use `pacman -Qqem > foreignpkglist.txt` to create the list of AUR and other foreign packages that have been explicitly installed.

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'

### Install packages from a list

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))

Tip: These tasks can be automated. See bacpacAUR, packupAUR, pacmanityAUR, and pugAUR for examples.

### Listing all changed files from packages

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 pacutils:

    # paccheck --md5sum --quiet

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

Note: This should not be used as is when suspecting malicious changes! In this case security precautions such as using a live medium and an independent source for the hash sums are advised.

### Reinstalling all packages

To reinstall all native packages, use:

    # pacman -Qqn | pacman -S -

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

Pacman preserves the installation reason by default.

Warning: To force all packages to be overwritten, use `--overwrite=*`, though this should be an absolute last resort. See System maintenance#Avoid certain pacman commands.

### Restore pacman's local database

See pacman/Restore local database.

### Recovering a USB key from existing install

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 `/newarch`)

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

### Viewing a single file inside a .pkg file

For example, if you want to see the contents of `/etc/systemd/logind.conf` supplied within the systemd package:

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

Or you can use vim to browse the archive:

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

### Find applications that use libraries from older packages

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 lsof, 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 (`.so` files). It may miss some dependencies, like those of Java or Python applications.

### Installing only content in required languages

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

Warning: Some users noted that removing locales has resulted in unintended consequences, even under Xorg.

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

## Performance

### Download speeds

When downloading packages pacman uses the mirrors in the order they are in `/etc/pacman.d/mirrorlist`. 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

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

#### wget

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

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

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

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

#### aria2

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.

Note: Using aria2c in pacman's XferCommand will not result in parallel downloads of multiple packages. Pacman invokes the XferCommand with a single package at a time and waits for it to complete before invoking the next. To download multiple packages in parallel, see Powerpill.

Install aria2, then edit `/etc/pacman.conf` by adding the following line to the `[options]` 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

Tip: This alternative configuration for using pacman with aria2 tries to simplify configuration and adds more configuration options.

See aria2c(1) § OPTIONS for used aria2c options.

- `-d, --dir`: The directory to store the downloaded file(s) as specified by pacman.
- `-o, --out`: The output file name(s) of the downloaded file(s).
- `%o`: Variable which represents the local filename(s) as specified by pacman.
- `%u`: Variable which represents the download URL as specified by pacman.

#### Other applications

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

- `snarf`: `XferCommand = /usr/bin/snarf -N %u`
- `lftp`: `XferCommand = /usr/bin/lftp -c pget %u`
- `axel`: `XferCommand = /usr/bin/axel -n 2 -v -a -o %o %u`
- `hget`: `XferCommand = /usr/bin/hget %u -n 2 -skip-tls false` (please read the documentation on the Github project page for more info)
- `saldl`: `XferCommand = /usr/bin/saldl -c6 -l4 -s2m -o %o %u` (please read the documentation on the project page for more info)

## Utilities

- Lostfiles — Script that identifies files not owned by any package.

  https://github.com/graysky2/lostfiles || lostfiles

- pacutils — Helper library for libalpm based programs.

  https://github.com/andrewgregory/pacutils || pacutils

- pkgfile — Tool that finds what package owns a file.

  https://github.com/falconindy/pkgfile || pkgfile

- pkgtools — Collection of scripts for Arch Linux packages.

  https://github.com/Daenyth/pkgtools || pkgtoolsAUR

- pkgtop — Interactive package manager and resource monitor designed for the GNU/Linux.

  https://github.com/orhun/pkgtop || pkgtop-gitAUR

- Powerpill — Uses parallel and segmented downloading through aria2 and Reflector to try to speed up downloads for pacman.

  https://xyne.dev/projects/powerpill/ || powerpillAUR

- repoctl — Tool to help manage local repositories.

  https://github.com/cassava/repoctl || repoctlAUR

- repose — An Arch Linux repository building tool.

  https://github.com/vodik/repose || repose

- snap-pac — Make pacman automatically use snapper to create pre/post snapshots like openSUSE's YaST.

  https://github.com/wesbarnett/snap-pac || snap-pac

- vrms-arch — A virtual Richard M. Stallman to tell you which non-free packages are installed.

  https://github.com/orospakr/vrms-arch || vrms-arch-gitAUR

### Graphical

Warning: PackageKit opens up system permissions by default, and is otherwise not recommended for general usage. See FS#50459 and FS#57943.

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

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

- Deepin App Store — Third party app store for DDE built with DTK, using PackageKit. Supports AppStream metadata.

  https://github.com/dekzi/dde-store || deepin-store

- Discover — Qt 5 application manager using PackageKit written in C++/QML. Supports AppStream metadata, Flatpak and firmware updates.

  https://userbase.kde.org/Discover || discover

- GNOME PackageKit — GTK 3 package manager using PackageKit written in C.

  https://freedesktop.org/software/PackageKit/ || gnome-packagekit

- GNOME Software — GTK 3 application manager using PackageKit written in C. Supports AppStream metadata, Flatpak and firmware updates.

  https://wiki.gnome.org/Apps/Software || gnome-software

- pcurses — Curses TUI pacman wrapper written in C++.

  https://github.com/schuay/pcurses || pcurses

- tkPacman — Tk pacman wrapper written in Tcl.

  https://sourceforge.net/projects/tkpacman || tkpacmanAUR

Category:

- Package manager

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