= Package management system

'''

[NOTE]
======

This page was automatically converted from https://fedoraproject.org/wiki/Package_management_system

It is probably

* Badly formatted
* Missing graphics and tables that do not covert well from mediawiki
* Out-of-date
* In need of other love

Please fix it, remove this notice, and then add to `_topic_map.yml`

Pull requests accepted at https://pagure.io/fedora-docs/fedora-howto

Once that is live, go to the original wiki page and add an `{{old}}`
tag, followed by a note like

....
{{admon/note|This page has a new home!|
This wiki page is no longer maintained. Please find the up-to-date
version at: https://docs.fedoraproject.org/whatever-the-url
}}
....

======

'''


[[package-management-system]]
Package Management System
-------------------------

[[introduction]]
Introduction
~~~~~~~~~~~~

Fedora is a distribution that uses a package management system. This
system is based on http://rpm.org[rpm] , the RPM Package Manager, with
several higher level tools built on top of it, most notably
https://www.freedesktop.org/software/PackageKit/[PackageKit] (default
gui) and link:Yum[ yum] (command line tool). As of Fedora 22, yum has
been replaced by link:Dnf[ dnf]. The Gnome Package Manager is another
GUI package manager.

[[advantages-of-package-management-systems]]
Advantages of package management systems
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Package management systems have many advantages:

* It's easy to query what version of a package is installed or
available.

* It's easy to remove a package entirely, making sure all its files are
gone.

* It's easy to verify the integrity of the packages files, so you can
see if it's been corrupted or tampered with.

* It's easy to upgrade a package by installing the new version and
removing all the old versions files. This will make sure not to leave
any lingering files from the old package around to confuse or break
things.

* It's easy to see what packages require or provide things that other
packages provide or require, so you can be sure to have the needed items
for the package to function correctly.

* It's easy to install or remove groups of packages.

* In many cases it's possible to downgrade back to a previous version of
a package, for example when a new version has a bug.

[[disadvantages-of-package-management-systems]]
Disadvantages of package management systems
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

* You are restricted to either using the versions of the package that
are available or having to make your own package if you need a different
version.

[[why-mixing-source-installs-and-packages-is-a-bad-idea]]
Why mixing source installs and packages is a bad idea
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Package management systems have no way to query or note when you bypass
them and install something from source. You should avoid mixing source
installs and packaged installs for (at least) the following reasons:

* You lose all the advantages above from a package managed system.

* Installing from source may overwrite, delete, or change existing files
that are in a package, making that package not function correctly.

* The source install may override a package install causing undefined
behavior in the package or source installed item.

* Installing from source makes it impossible or very difficult for
anyone to help you debug issues, since versions can't be easily queried
and integrity checked.

* Fedora packages may include patches or configuration to work with
other packages, but upstream source does not, leading to loss of
functionality.

* Software installed from source will not upgrade with package managed
packages, leading to breakage in the source install package on upgrades
or os updates.

Strongly consider making your own package if you need a different
version or a version of some package with changes. See:
link:How_to_create_an_RPM_package[How to create a RPM package]

[[preferred-search-order-for-a-software]]
Preferred search order for a software
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

If some software is missing in your installation then you should try the
following steps to get the packaged version:

1.  Search in Fedora ( 'yum|dnf search foo' or search for 'foo' in the
PackageKit gui )
2.  Try one of the available link:Third_party_repositories[ 3rd party]
repositories
3.  link:How_to_create_an_RPM_package[ Build your own package]

[[package-management-tools]]
Package Management tools
~~~~~~~~~~~~~~~~~~~~~~~~

link:Dnf[ dnf] - Dandified Yum

link:Yum[ yum] - Yellowdog Updater Modified

https://www.freedesktop.org/software/PackageKit/[PackageKit] -
PackageKit gui tool ('add/remove software' in your menu)

http://rpm.org[rpm] - RPM package manager.

http://ww1.yum-extender.org/[yumex] - Yum Extender.

Category:Software_Management[Category:Software Management]
'''

See a typo, something missing or out of date, or anything else which can be
improved? Edit this document at https://pagure.io/fedora-docs/fedora-howto.
