- Pacman
- Содержание
- Общее
- Использование
- Установка и удаление пакетов
- Обновление системы
- Получение списка установленных пакетов для быстрого восстановления системы
- Запросы к базе данных пакетов
- Одновременный поиск в репозитории и среди установленных пакетов
- Другое использование
- Настройка
- Основные опции
- Репозитории
- pacman
- Contents
- Usage
- Installing packages
- Installing specific packages
- Installing package groups
- Removing packages
- Upgrading packages
- Querying package databases
- Pactree
- Database structure
- Cleaning the package cache
- Additional commands
- Installation reason
- Search for a package that contains a specific file
- What happens during package install/upgrade/removal
- Configuration
- General options
- Comparing versions before updating
- Enabling parallel downloads
- Skip package from being upgraded
- Skip package group from being upgraded
- Skip file from being upgraded
- Skip files from being installed to system
- Maintain several configuration files
- Hooks
- Repositories and mirrors
- Package security
- Troubleshooting
- «Failed to commit transaction (conflicting files)» error
- «Failed to commit transaction (invalid or corrupted package)» error
- «Failed to init transaction (unable to lock database)» error
- Packages cannot be retrieved on installation
- Pacman crashes during an upgrade
- Manually reinstalling pacman
- Using pacman-static
- Using an external pacman
- By manually extracting
- «Unable to find root device» error after rebooting
- «Warning: current locale is invalid; using default «C» locale» error
- Pacman does not honor proxy settings
- How do I reinstall all packages, retaining information on whether something was explicitly installed or as a dependency?
- «Cannot open shared object file» error
- Freeze of package downloads
- Failed retrieving file ‘core.db’ from mirror
- error: ‘local-package.pkg.tar’: permission denied
- error: could not determine cachedir mount point /var/cache/pacman/pkg
Pacman
Содержание
Общее
Arch Linux использует менеджер пакетов Pacman, который соединяет в себе простой формат бинарных пакетов и простую в использовании систему сборки, позволяющую пользователям с легкостью управлять и настраивать под себя пакеты, вне зависимости от того, официальные ли они или собранные пользователем. Система репозиториев позволяет пользователям создавать и поддерживать собственные репозитории с собранными пакетами, что способствует росту сообщества.
Pacman может держать систему в новейшем состоянии, синхронизируя пакеты с главным сервером, тем самым позволяя сознательному администратору поддерживать систему. Клиент-серверная модель позволяет скачивать/устанавливать пакеты одной командой со всеми требуемыми зависимостями (похоже на apt-get от Debian).
Pacman был написан на языке C и поэтому он быстрый, легкий. Он использует .tar.gz формат пакетов, эти пакеты извлекаются быстрее.
Использование
Pacman является универсальным менеджером пакетов, способным скачивать, устанавливать и обновлять пакеты и из репозитория, и собственные локальные, удалять и искать их. Вам только необходимо знать, какой ключ используется функцией для желаемых действий. Вот несколько наиболее часто используемых:
Установка и удаление пакетов
Перед установкой и обновлением пакетов полезно синхронизировать базу данных локально установленных пакетов с удалёнными репозиториями
Для того чтобы установить или обновить один пакет или группу пакетов (включая зависимости), используйте следующую команду:
Иногда пакет имеет несколько версий в разных репозиториях (например в extra и testing). Вы можете указать, какой именно вы хотите установить:
Вы можете совмещать параметры, например, эта команда синхронизирует базы данных и установит пакет:
Удалить пакет (оставляя все зависимости в системе):
Удалить пакет со всеми зависимостями, не используемыми другими установленными пакетами:
По умолчанию Pacman создает резервные копии конфигурационных файлов удаляемых приложений с помощью добавления к ним расширения *. pacsave. Если вы хотите удалить эти файлы при удалении соответствующего пакета (подсказка: это операция называется purging в Debian-системах), вы можете использовать:
Конечно, это может быть дополнено -s, чтобы также удалить ненужные теперь зависимости. Таким образом, команда полностью удалит пакет, его конфигурации и все зависимости, которые больше не нужны:
Обновление системы
Pacman может обновить все пакеты системы одной командой. Количество пакетов зависит от того, насколько ваша система современна.
NB: вы можете синхронизировать базы данных репозиториев И обновить все установленные пакеты одной командой:
Хорошо выполнять эту команду каждые несколько дней.
Получение списка установленных пакетов для быстрого восстановления системы
Если ваша система упала и ее сложно восстановить то неплохо бы иметь список пакетов которые были установлены в ней.
Сохранить в файл pkglist список пакетов установленных в системе:
Сохраните этот файл на флешке или еще где-нибудь.
Если вдруг с вашей системой случится что-либо неприятное то установленые пакеты легко можно восстановить:
Запросы к базе данных пакетов
- Поиск пакетов в репозиториях, вы можете указать только часть названия:
- Поиск среди установленных пакетов:
- Вывод информации о пакете:
- Вывод списка файлов пакета:
- Какой пакет является владельцем файла?
- Перечислите все пакеты, больше не требуемые как зависимости(сироты):
- Удалить всех сирот: (Проверьте сначала вывод команды pacman -Qdt.)
Одновременный поиск в репозитории и среди установленных пакетов
Вы можете использовать следующий bash скрипт в качестве эквивалента для одновременного вызова pacman -Ss foo и pacman -Qs foo, для того чтобы узнать, какие из пакетов в выводе установлены на вашей системе. Последние будут помечены звёздочкой.
Сохраните этот скрипт в каталоге, включенном в переменную PATH (например,
/bin/), и назовите его pacsearch. Сделайте его исполняемым с помощью
Теперь если вы напишете, например:
вывод может выглядеть так:
В этом случае вы узнаете, что ни один из вышеперечисленных пакетов (кроме самого qt) на вашей системе не установлен.
NB1: был добавлен запрос на flyspray с предложением интегрировать вышеуказанную функциональность в сам pacman, чтобы ‘грязные’ хитрости bash стали стать ненужными с последующими версиями pacman.
NB2: вы можете изменить этот bash скрипт с помощью этого wiki, для того чтобы установленные пакеты были выделены различными цветами в выводе.
Другое использование
- Скачать пакет, но не устанавливать его:
- Установить локальный пакет (не из репозитория):
Вы можете ввести ссылку:
- Очистка кэша pacman`а (/var/cache/pacman/pkg):
- Для того, чтобы переустановить все пакеты в вашей системе (которые доступны в репозитории):
Для более детальной информацией о возможных ключах обратитесь к pacman —help или man pacman.
Настройка
Настройки pacman`a находятся в /etc/pacman.conf . Важными секциями являются:
Основные опции
Основные опции находятся в секции [options]. Есть одна полезная опция IgnorePkg. Например, если вы изменяли или накладывали патч на пакет, добавление его в IgnorePkg укажет pacman’у не обновлять его при выходе следующей версии пакета. Но pacman всё же предупредит вас о том, что доступна более свежая версия, так что в итоге вы можете обновить ваш изменённый пакет. Опция также полезна для БОЛЬШИХ пакетов (например, openoffice-base), если вы хотите избежать скачивания и обновления всего пакета каждый раз, когда в репозитории появляется маленькое изменение. Поскольку pacman всё равно предупредит вас о последней версии, вы можете обновить пакет вручную.
Репозитории
В этой секции вы указываете используемые репозитории. Они могут быть указаны напрямую или как файл, содержащий список серверов. Последнее удобно для официальных репозиториев, имеющих множество зеркал.
За более подробной информацией обратитесь к man pacman.
Источник
pacman
The pacman package manager is one of the major distinguishing features of Arch Linux. It combines a simple binary package format with an easy-to-use build system. The goal of pacman is to make it possible to easily manage packages, whether they are from the official repositories or the user’s own builds.
Pacman keeps the system up-to-date by synchronizing package lists with the master server. This server/client model also allows the user to download/install packages with a simple command, complete with all required dependencies.
Pacman is written in the C programming language and uses the bsdtar(1) tar format for packaging.
Contents
Usage
What follows is just a small sample of the operations that pacman can perform. To read more examples, refer to pacman(8) .
Installing packages
A package is an archive containing:
- all of the (compiled) files of an application
- metadata about the application, such as application name, version, dependencies, etc.
- installation files and directives for pacman
- (optionally) extra files to make your life easier, such as a start/stop script
Arch’s package manager pacman can install, update, and remove those packages. Using packages instead of compiling and installing programs yourself has various benefits:
- easily updatable: pacman will update existing packages as soon as updates are available
- dependency checks: pacman handles dependencies for you, you only need to specify the program and pacman installs it together with every other program it needs
- clean removal: pacman has a list of every file in a package; this way, no files are unintentionally left behind when you decide to remove a package.
Installing specific packages
To install a single package or list of packages, including dependencies, issue the following command:
To install a list of packages with regex (see this forum thread):
Sometimes there are multiple versions of a package in different repositories (e.g. extra and testing). To install the version from the extra repository in this example, the repository needs to be defined in front of the package name:
To install a number of packages sharing similar patterns in their names one can use curly brace expansion. For example:
This can be expanded to however many levels needed:
Virtual packages
A virtual package is a special package which does not exist by itself, but is provided by one or more other packages. Virtual packages allow other packages to not name a specific package as a dependency, in case there are several candidates. Virtual packages cannot be installed by their name, instead they become installed in your system when you have install a package providing the virtual package.
Installing package groups
Some packages belong to a group of packages that can all be installed simultaneously. For example, issuing the command:
will prompt you to select the packages from the gnome group that you wish to install.
Sometimes a package group will contain a large amount of packages, and there may be only a few that you do or do not want to install. Instead of having to enter all the numbers except the ones you do not want, it is sometimes more convenient to select or exclude packages or ranges of packages with the following syntax:
which will select packages 1 through 10 and 15 for installation, or:
which will select all packages except 5 through 8 and 2 for installation.
To see what packages belong to the gnome group, run:
Also visit https://archlinux.org/groups/ to see what package groups are available.
Removing packages
To remove a single package, leaving all of its dependencies installed:
To remove a package and its dependencies which are not required by any other installed package:
The above may sometimes refuse to run when removing a group which contains otherwise needed packages. In this case try:
To remove a package, its dependencies and all the packages that depend on the target package:
To remove a package, which is required by another package, without removing the dependent package:
Pacman saves important configuration files when removing certain applications and names them with the extension: .pacsave. To prevent the creation of these backup files use the -n option:
Upgrading packages
Pacman can update all packages on the system with just one command. This could take quite a while depending on how up-to-date the system is. The following command synchronizes the repository databases and updates the system’s packages, excluding «local» packages that are not in the configured repositories:
Querying package databases
Pacman queries the local package database with the -Q flag, the sync database with the -S flag and the files database with the -F flag. See pacman -Q —help , pacman -S —help and pacman -F —help for the respective suboptions of each flag.
Pacman can search for packages in the database, searching both in packages’ names and descriptions:
Sometimes, -s ‘s builtin ERE (Extended Regular Expressions) can cause a lot of unwanted results, so it has to be limited to match the package name only; not the description nor any other field:
To search for already installed packages:
To search for package file names in remote packages:
To display extensive information about a given package:
For locally installed packages:
Passing two -i flags will also display the list of backup files and their modification states:
To retrieve a list of the files installed by a package:
To retrieve a list of the files installed by a remote package:
To verify the presence of the files installed by a package:
Passing the k flag twice will perform a more thorough check.
To query the database to know which package a file in the file system belongs to:
To query the database to know which remote package a file belongs to:
To list all packages no longer required as dependencies (orphans):
To list all packages explicitly installed and not required as dependencies:
Pactree
To view the dependency tree of a package:
To view the dependant tree of a package, pass the reverse flag -r to pactree, or use whoneeds from pkgtools AUR .
Database structure
The pacman databases are normally located at /var/lib/pacman/sync . For each repository specified in /etc/pacman.conf there will be a corresponding database file located there. Database files are gzipped tar archives containing one directory for each package, for example for the which package:
The desc file contains meta data such as the package description, dependencies, file size and MD5 hash.
Cleaning the package cache
Pacman stores its downloaded packages in /var/cache/pacman/pkg/ and does not remove the old or uninstalled versions automatically. This has some advantages:
- It allows to downgrade a package without the need to retrieve the previous version through other means, such as the Arch Linux Archive.
- A package that has been uninstalled can easily be reinstalled directly from the cache folder, not requiring a new download from the repository.
However, it is necessary to deliberately clean up the cache periodically to prevent the folder to grow indefinitely in size.
The paccache(8) script, provided within the pacman-contrib package, deletes all cached versions of installed and uninstalled packages, except for the most recent three, by default:
Enable and start paccache.timer to discard unused packages weekly.
You can also define how many recent versions you want to keep. To retain only one past version use:
Add the -u / —uninstalled switch to limit the action of paccache to uninstalled packages. For example to remove all cached versions of uninstalled packages, use the following:
See paccache -h for more options.
Pacman also has some built-in options to clean the cache and the leftover database files from repositories which are no longer listed in the configuration file /etc/pacman.conf . However pacman does not offer the possibility to keep a number of past versions and is therefore more aggressive than paccache default options.
To remove all the cached packages that are not currently installed, and the unused sync database, execute:
To remove all files from the cache, use the clean switch twice, this is the most aggressive approach and will leave nothing in the cache folder:
pkgcacheclean AUR and pacleaner AUR are two further alternatives to clean the cache.
Additional commands
Download a package without installing it:
Install a ‘local’ package that is not from a remote repository (e.g. the package is from the AUR):
To keep a copy of the local package in pacman’s cache, use:
Install a ‘remote’ package (not from a repository stated in pacman’s configuration files):
To inhibit the -S , -U and -R actions, -p can be used.
Pacman always lists packages to be installed or removed and asks for permission before it takes action.
Installation reason
The pacman database distinguishes the installed packages in two groups according to the reason why they were installed:
- explicitly-installed: the packages that were literally passed to a generic pacman -S or -U command;
- dependencies: the packages that, despite never (in general) having been passed to a pacman installation command, were implicitly installed because required by another package that was explicitly installed.
When installing a package, it is possible to force its installation reason to dependency with:
When reinstalling a package, though, the current installation reason is preserved by default.
The list of explicitly-installed packages can be shown with pacman -Qe , while the complementary list of dependencies can be shown with pacman -Qd .
To change the installation reason of an already installed package, execute:
Use —asexplicit to do the opposite operation.
Search for a package that contains a specific file
Sync the files database:
Search for a package containing a file, e.g.:
For advanced functionality install pkgfile, which uses a separate database with all files and their associated packages.
What happens during package install/upgrade/removal
When successful, the workflow of a transaction follows five high-level steps plus pre/post transaction hooks:
- Initialize the transaction if there is not a database lock
- Choose which packages will be added or removed in the transaction
- Prepare the transaction, based on flags, by performing sanity checks on the sync databases, packages, and their dependencies
- Commit the transaction:
- When applicable, download packages ( _alpm_sync_load )
- If pre-existing pacman PreTransaction hooks apply, they are executed.
- Packages are removed that are to-be-replaced, conflicting, or explicitly targeted to be removed
- If there packages to add, then each package is committed
- If the package has an install script, its pre_install function is executed (or pre_upgrade or pre_remove in the case of an upgraded or removed package).
- Pacman deletes all the files from a pre-existing version of the package (in the case of an upgraded or removed package). However, files that were marked as configuration files in the package are kept (see /Pacnew and Pacsave).
- Pacman untars the package and dumps its files into the file system (in the case of an installed or upgraded package). Files that would overwrite kept, and manually modified, configuration files (see previous step), are stored with a new name (.pacnew).
- If the package has an install script, its post_install function is executed (or post_upgrade or post_remove in the case of an upgraded or removed package).
- If pacman PostTransaction hooks that exist at the end of the transaction apply, they are executed.
- Release the transaction and transaction resource (i.e. database lock)
Configuration
Pacman’s settings are located in /etc/pacman.conf : this is the place where the user configures the program to work in the desired manner. In-depth information about the configuration file can be found in pacman.conf(5) .
General options
General options are in the [options] section. Read pacman.conf(5) or look in the default pacman.conf for information on what can be done here.
Comparing versions before updating
To see old and new versions of available packages, uncomment the «VerbosePkgLists» line in /etc/pacman.conf . The output of pacman -Syu will be like this:
Enabling parallel downloads
Pacman 6.0 introduced the option to download packages in parallel. ParallelDownloads under [options] needs to be set to a positive integer in /etc/pacman.conf to use this feature (e.g., 5 ). Packages will otherwise be downloaded sequentially if this option is unset.
Skip package from being upgraded
To have a specific package skipped when upgrading the system, add this line in the [options] section:
For multiple packages use a space-separated list, or use additional IgnorePkg lines. Also, glob patterns can be used. If you want to skip packages just once, you can also use the —ignore option on the command-line — this time with a comma-separated list.
It will still be possible to upgrade the ignored packages using pacman -S : in this case pacman will remind you that the packages have been included in an IgnorePkg statement.
Skip package group from being upgraded
As with packages, skipping a whole package group is also possible:
Skip file from being upgraded
All files listed with a NoUpgrade directive will never be touched during a package install/upgrade, and the new files will be installed with a .pacnew extension.
Skip files from being installed to system
To always skip installation of specific directories list them under NoExtract . For example, to avoid installation of systemd units use this:
Later rules override previous ones, and you can negate a rule by prepending ! .
Maintain several configuration files
If you have several configuration files (e.g. main configuration and configuration with testing repository enabled) and would have to share options between configurations you may use Include option declared in the configuration files, e.g.:
where /path/to/common/settings file contains the same options for both configurations.
Hooks
Pacman can run pre- and post-transaction hooks from the /usr/share/libalpm/hooks/ directory; more directories can be specified with the HookDir option in pacman.conf , which defaults to /etc/pacman.d/hooks . Hook file names must be suffixed with .hook. Pacman hooks are not interactive.
Pacman hooks are used, for example, in combination with systemd-sysusers and systemd-tmpfiles to automatically create system users and files during the installation of packages. For example, tomcat8 specifies that it wants a system user called tomcat8 and certain directories owned by this user. The pacman hooks systemd-sysusers.hook and systemd-tmpfiles.hook invoke systemd-sysusers and systemd-tmpfiles when pacman determines that tomcat8 contains files specifying users and tmp files.
For more information on alpm hooks, see alpm-hooks(5) .
Repositories and mirrors
Besides the special [options] section, each other [section] in pacman.conf defines a package repository to be used. A repository is a logical collection of packages, which are physically stored on one or more servers: for this reason each server is called a mirror for the repository.
Repositories are distinguished between official and unofficial. The order of repositories in the configuration file matters; repositories listed first will take precedence over those listed later in the file when packages in two repositories have identical names, regardless of version number. In order to use a repository after adding it, you will need to upgrade the whole system first.
Each repository section allows defining the list of its mirrors directly or in a dedicated external file through the Include directive; for example, the mirrors for the official repositories are included from /etc/pacman.d/mirrorlist . See the Mirrors article for mirror configuration.
Package security
Pacman supports package signatures, which add an extra layer of security to the packages. The default configuration, SigLevel = Required DatabaseOptional , enables signature verification for all the packages on a global level. This can be overridden by per-repository SigLevel lines. For more details on package signing and signature verification, take a look at pacman-key.
Troubleshooting
«Failed to commit transaction (conflicting files)» error
If you see the following error: [1]
This is happening because pacman has detected a file conflict, and by design, will not overwrite files for you. This is by design, not a flaw.
The problem is usually trivial to solve. A safe way is to first check if another package owns the file ( pacman -Qo /path/to/file ). If the file is owned by another package, file a bug report. If the file is not owned by another package, rename the file which ‘exists in filesystem’ and re-issue the update command. If all goes well, the file may then be removed.
If you had installed a program manually without using pacman, for example through make install , you have to remove/uninstall this program with all of its files. See also Pacman tips#Identify files not owned by any package.
Every installed package provides a /var/lib/pacman/local/package-version/files file that contains metadata about this package. If this file gets corrupted, is empty or goes missing, it results in file exists in filesystem errors when trying to update the package. Such an error usually concerns only one package. Instead of manually renaming and later removing all the files that belong to the package in question, you may explicitly run pacman -S —overwrite glob package to force pacman to overwrite files that match glob .
«Failed to commit transaction (invalid or corrupted package)» error
Look for .part files (partially downloaded packages) in /var/cache/pacman/pkg/ and remove them (often caused by usage of a custom XferCommand in pacman.conf ).
«Failed to init transaction (unable to lock database)» error
When pacman is about to alter the package database, for example installing a package, it creates a lock file at /var/lib/pacman/db.lck . This prevents another instance of pacman from trying to alter the package database at the same time.
If pacman is interrupted while changing the database, this stale lock file can remain. If you are certain that no instances of pacman are running then delete the lock file:
Packages cannot be retrieved on installation
This error manifests as Not found in sync db , Target not found or Failed retrieving file .
Firstly, ensure the package actually exists. If certain the package exists, your package list may be out-of-date. Try running pacman -Syu to force a refresh of all package lists and upgrade. Also make sure the selected mirrors are up-to-date and repositories are correctly configured.
It could also be that the repository containing the package is not enabled on your system, e.g. the package could be in the multilib repository, but multilib is not enabled in your pacman.conf .
Pacman crashes during an upgrade
In the case that pacman crashes with a «database write» error while removing packages, and reinstalling or upgrading packages fails thereafter, do the following:
- Boot using the Arch installation media. Preferably use a recent media so that the pacman version matches/is newer than the system.
- Mount the system’s root filesystem, e.g., mount /dev/sdaX /mnt as root, and check the mount has sufficient space with df -h
- Mount the proc, sys and dev filesystems as well: mount -t proc proc /mnt/proc; mount —rbind /sys /mnt/sys; mount —rbind /dev /mnt/dev
- If the system uses default database and directory locations, you can now update the system’s pacman database and upgrade it via pacman —sysroot /mnt -Syu as root.
- Alternatively, if you cannot update/upgrade, refer to Pacman/Tips and tricks#Reinstalling all packages.
- After the upgrade, one way to double-check for not upgraded but still broken packages: find /mnt/usr/lib -size 0
- Followed by a re-install of any still broken package via pacman —sysroot /mnt -S package .
Manually reinstalling pacman
Using pacman-static
pacman-static AUR is a statically compiled version of pacman, so it will be able to run even when the libraries on the system are not working. This can also come in handy when a partial upgrade was performed and pacman can not run anymore.
The pinned comment and the PKGBUILD provides a way to directly download the binary, which can be used to reinstall pacman or to upgrade the entire system in case of partial upgrades.
Using an external pacman
If even pacman-static does not work, it is possible to recover using an external pacman. One of the easiest methods to do so is by using the archiso and simply using —sysroot or —root to specify the mount point. See Chroot#Using chroot on how to mount the necessary filesystems required by —sysroot .
By manually extracting
Even if pacman is terribly broken, you can fix it manually by downloading the latest packages and extracting them to the correct locations. The rough steps to perform are:
- Determine the pacman dependencies to install
- Download each package from a mirror of your choice
- Extract each package to root
- Reinstall these packages with pacman -S —overwrite to update the package database accordingly
- Do a full system upgrade
If you have a healthy Arch system on hand, you can see the full list of dependencies with:
But you may only need to update a few of them depending on your issue. An example of extracting a package is
Note the use of the w flag for interactive mode. Running non-interactively is very risky since you might end up overwriting an important file. Also take care to extract packages in the correct order (i.e. dependencies first). This forum post contains an example of this process where only a couple pacman dependencies are broken.
«Unable to find root device» error after rebooting
Most likely the initramfs became corrupted during a kernel update (improper use of pacman’s —overwrite option can be a cause). There are two options; first, try the Fallback entry.
Once the system starts, run this command (for the stock linux kernel) either from the console or from a terminal to rebuild the initramfs image:
If that does not work, from a current Arch release (CD/DVD or USB stick), mount your root and boot partitions. Then chroot using arch-chroot:
Reinstalling the kernel (the linux package) will automatically re-generate the initramfs image with mkinitcpio -p linux . There is no need to do this separately.
Afterwards, it is recommended that you run exit , umount /mnt/
«Warning: current locale is invalid; using default «C» locale» error
As the error message says, your locale is not correctly configured. See Locale.
Pacman does not honor proxy settings
Make sure that the relevant environment variables ( $http_proxy , $ftp_proxy etc.) are set up. If you use pacman with sudo, you need to configure sudo to pass these environment variables to pacman. Also, ensure the configuration of dirmngr has honor-http-proxy in /etc/pacman.d/gnupg/dirmngr.conf to honor the proxy when refreshing the keys.
How do I reinstall all packages, retaining information on whether something was explicitly installed or as a dependency?
To reinstall all the native packages: pacman -Qnq | pacman -S — or pacman -S $(pacman -Qnq) (the -S option preserves the installation reason by default).
You will then need to reinstall all the foreign packages, which can be listed with pacman -Qmq .
«Cannot open shared object file» error
It looks like previous pacman transaction removed or corrupted shared libraries needed for pacman itself.
To recover from this situation you need to unpack required libraries to your filesystem manually. First find what package contains the missed library and then locate it in the pacman cache ( /var/cache/pacman/pkg/ ). Unpack required shared library to the filesystem. This will allow to run pacman.
Now you need to reinstall the broken package. Note that you need to use —overwrite flag as you just unpacked system files and pacman does not know about it. Pacman will correctly replace our shared library file with one from package.
That’s it. Update the rest of the system.
Freeze of package downloads
Some issues have been reported regarding network problems that prevent pacman from updating/synchronizing repositories. [2] [3] When installing Arch Linux natively, these issues have been resolved by replacing the default pacman file downloader with an alternative (see Improve pacman performance for more details). When installing Arch Linux as a guest OS in VirtualBox, this issue has also been addressed by using Host interface instead of NAT in the machine properties.
Failed retrieving file ‘core.db’ from mirror
If you receive this error message with correct mirrors, try setting a different name server.
error: ‘local-package.pkg.tar’: permission denied
If you want to install a package on an sshfs mount using pacman -U and receive this error, move the package to a local directory and try to install again.
error: could not determine cachedir mount point /var/cache/pacman/pkg
Upon executing, e.g., pacman -Syu inside a chroot environment an error is encountered:
This is frequently caused by the chroot directory not being a mountpoint when the chroot is entered. See the note at Install Arch Linux from existing Linux#Downloading basic tools for a solution, and arch-chroot(8) for an explanation and an example of using bind mounting to make the chroot directory a mountpoint.
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