pacman
Manage software packages (install, update, remove)
TLDR
[S]ynchronize and update all packages
Install a new package
[R]emove a package and its dependencies
Search ([s]) the package database for a regex or keyword
Search the database for packages containing a specific [F]ile
List only the [e]xplicitly installed packages and versions
List orphan packages (installed as [d]ependencies but not actually required by any package)
Empty the entire pacman cache
SYNOPSIS
pacman [generic_options] [{command [options] [targets]}]
PARAMETERS
-S
Sync: install/upgrade packages from repos
-R
Remove packages (no deps by default)
-Q
Query installed packages
-U
Upgrade/install local .pkg.tar.zst package
-Fs
Search files owned by packages in sync DB
-F
Search files in sync DB
-D
Modify package database (e.g., mark explicit)
-T
Test dependencies
--sysupgrade
Upgrade all packages (-Su)
--refresh
Refresh sync DB (-Syy)
--needed
Skip installed packages
--overwrite
Overwrite conflicting files
-b
Alternative root prefix
-c
Cache directory
-d
Skip dependency checks
--debug
Enable debug output
-q
Quiet mode
--noconfirm
No confirmation prompts
-v
Verbose output
--print
Print targets instead of acting
DESCRIPTION
pacman is the default package manager for Arch Linux and its derivatives. It serves as a front-end to libalpm, a C library for package management. Pacman handles installing, updating, removing, and querying packages from both official repositories and local files. Key features include support for split packages (one source yielding multiple binaries), automatic dependency resolution, file conflict detection, and progress bars.
It operates in several modes: synchronization (-S), removal (-R), querying (-Q), file searches (-F/-Fs), and local upgrades (-U). Common workflows include pacman -Syu for full system upgrades (sync databases, then upgrade all packages) and pacman -S package for installing specific ones. Pacman requires root privileges for most operations and uses pacman.conf(5) for configuration, defining repositories, mirrors, and caches.
Pacman emphasizes simplicity, speed, and rolling-release model suitability. It downloads packages as .pkg.tar.zst, verifies checksums and signatures, then extracts to the filesystem. Orphan detection, explicit package marking, and hooks for pre/post actions enhance usability. While powerful, it demands caution to avoid dependency breakage.
CAVEATS
Requires root for most ops; always run pacman -Syu for upgrades; partial upgrades risky; GPG keys must be imported for signatures.
DATABASES
Sync DBs in /var/lib/pacman/sync/; local DB in /var/lib/pacman/; refresh with -Sy.
HOOKS
Custom scripts in /usr/share/libalpm/hooks/ run pre/post operations.
HISTORY
Developed by Judd Vint (2002-2006) for Arch Linux; rewritten in C; maintained by Pacman Development Team since 2006; version 6.x supports zstd compression.
