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[[ro:ABS]]
 
[[ru:Arch Build System]]
 
[[ru:Arch Build System]]
[[tr:Arch_derleme_sistemi]]
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[[tr:Arch derleme sistemi]]
[[zh-CN:Arch Build System]]
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[[zh-hans:Arch Build System]]
[[zh-TW:Arch Build System]]
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[[zh-hant:Arch Build System]]
{{Article summary start}}
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{{Related articles start}}
{{Article summary text|The Arch Build System is a ports-like system for building and packaging software from source code. This article includes a general overview of the ABS followed by detailed usage instructions.}}
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{{Related|Arch packaging standards}}
{{Article summary heading|Overview}}
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{{Related|Arch User Repository}}
{{Article summary text|{{Package management overview}}}}
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{{Related|Creating packages}}
{{Article summary heading|Related}}
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{{Related|Kernel Compilation with ABS}}
{{Article summary wiki|ABS FAQ}}
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{{Related|makepkg}}
{{Article summary wiki|Arch Packaging Standards}}
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{{Related|Official repositories}}
{{Article summary wiki|Creating Packages}}
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{{Related|pacman}}
{{Article summary wiki|Kernel Compilation with ABS}}
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{{Related|PKGBUILD}}
{{Article summary end}}
+
{{Related|Patching in ABS}}
 +
{{Related articles end}}
 +
 
 +
This article provides an overview of the Arch Build System (ABS) along with a walkthrough for beginners. It is not intended to be a complete reference guide.
  
This article provides an overview of the Arch Build System along with a walkthrough for beginners. It is not a complete reference guide! For a quick and simple introduction to the ABS, see the [[ABS FAQ]]. If you need more information, please reference the man pages.
 
{{Note|ABS syncs once a day so it may lag behind what is already available in the repositories.}}
 
 
== What is the Arch Build System? ==
 
== What is the Arch Build System? ==
  
The Arch Build System, '''ABS''' for short, is a ''ports-like'' system for building and packaging software from source code. While [[pacman]] is the specialized Arch tool for binary package management (including packages built with the ABS), ABS is a collection of tools for compiling source into installable {{ic|.pkg.tar.xz}} packages.
+
The Arch Build System is a ''ports-like'' system for building and packaging software from source code. While [[pacman]] is the specialized Arch tool for binary package management (including packages built with the ABS), ABS is a collection of tools for compiling source into installable {{ic|.pkg.tar.xz}} packages.
  
 
=== What is a ports-like system? ===
 
=== What is a ports-like system? ===
Line 38: Line 40:
 
''Ports'' is a system used by *BSD to automate the process of building software from source code. The system uses a ''port'' to download, unpack, patch, compile, and install the given software. A ''port'' is merely a small directory on the user's computer, named after the corresponding software to be installed, that contains a few files with the instructions for building and installing the software from source. This makes installing software as simple as typing {{ic|make}} or {{ic|make install clean}} within the port's directory.
 
''Ports'' is a system used by *BSD to automate the process of building software from source code. The system uses a ''port'' to download, unpack, patch, compile, and install the given software. A ''port'' is merely a small directory on the user's computer, named after the corresponding software to be installed, that contains a few files with the instructions for building and installing the software from source. This makes installing software as simple as typing {{ic|make}} or {{ic|make install clean}} within the port's directory.
  
=== '''ABS''' is a similar concept ===
+
=== ABS is a similar concept ===
  
ABS is made up of a directory tree (the ABS tree) residing under {{ic|/var/abs}}. This tree contains many subdirectories, each within a category and each named by their respective package. This tree represents (but does not contain) all ''official Arch software'', retrievable through the SVN system. You may refer to each package-named subdirectory as an 'ABS', much the way one would refer to a 'port'. These ABS (or subdirectories) do not contain the software package nor the source but rather a [[PKGBUILD]] file (and sometimes other files). A PKGBUILD is a simple Bash build script -- a text file containing the compilation and packaging instructions as well as the URL of the appropriate '''source''' tarball to be downloaded. (The most important component of ABS are PKGBUILDs.) By issuing the ABS [[makepkg]] command, the software is first compiled and then ''packaged'' within the build directory before being installed. Now you may use [[pacman]], the Arch Linux package manager, to install, upgrade, and remove your new package.
+
ABS is made up of a directory tree that can be checked out using SVN. This tree represents, but does not contain, all official Arch software. Subdirectories do not contain the software package nor the source but rather a [[PKGBUILD]] file and sometimes other files. By issuing [[makepkg]] inside a directory containing a PKGBUILD, the software is first compiled and then packaged within the build directory. Then you can use [[pacman]] to install or upgrade your new package.
  
 
=== ABS overview ===
 
=== ABS overview ===
Line 46: Line 48:
 
'ABS' may be used as an umbrella term since it includes and relies on several other components; therefore, though not technically accurate, 'ABS' can refer to the following tools as a complete toolkit:
 
'ABS' may be used as an umbrella term since it includes and relies on several other components; therefore, though not technically accurate, 'ABS' can refer to the following tools as a complete toolkit:
  
; ABS tree: The ABS directory structure; an SVN hierarchy under {{ic|/var/abs/}} on your (local) machine. It contains many subdirectories, named for all available official Arch Linux software from repositories specified in {{ic|/etc/abs.conf}}, but not the packages themselves. The tree is created after installing the {{Pkg|abs}} package with [[pacman]] and subsequently running the {{ic|abs}} script.
+
; SVN tree: The directory structure containing files needed to build all official packages but not the packages themselves nor the source files of the software. It is available in [https://www.archlinux.org/svn/ svn] and [https://projects.archlinux.org/svntogit/packages.git/ git] repositories.
  
; [[PKGBUILD]]s: A [[Bash]] script that contains the URL of the source code along with the compilation and packaging instructions.
+
; [[PKGBUILD]]: A [[Bash]] script that contains the URL of the source code along with the compilation and packaging instructions.
  
; [[makepkg]]: ABS shell command tool which reads the PKGBUILDs, automatically downloads and compiles the sources and creates a {{ic|.pkg.tar*}} according to the {{ic|PKGEXT}} array in {{ic|makepkg.conf}}. You may also use makepkg to make your own custom packages from the [[AUR]] or third-party sources. (See the [[Creating Packages]] wiki article.)
+
; [[makepkg]]: shell command tool which reads the PKGBUILDs, automatically downloads and compiles the sources and creates a {{ic|.pkg.tar*}} according to the {{ic|PKGEXT}} array in {{ic|makepkg.conf}}. You may also use makepkg to make your own custom packages from the [[AUR]] or third-party sources. See [[Creating packages]] for more information.
  
 
; [[pacman]]: pacman is completely separate, but is necessarily invoked either by makepkg or manually, to install and remove the built packages and for fetching dependencies.
 
; [[pacman]]: pacman is completely separate, but is necessarily invoked either by makepkg or manually, to install and remove the built packages and for fetching dependencies.
  
; [[Arch User Repository|AUR]]: The Arch User Repository is separate from ABS but AUR (unsupported) PKGBUILDs are built using makepkg to compile and package up software. In contrast to the ABS tree on your local machine, the AUR exists as a website interface. It contains many thousands of user-contributed PKGBUILDs for software which is unavailable as an official Arch package. If you need to build a package outside the official Arch tree, chances are it is in the AUR.
+
; [[AUR]]: The Arch User Repository is separate from ABS but AUR (unsupported) PKGBUILDs are built using makepkg to compile and package up software. In contrast to the ABS tree on your local machine, the AUR exists as a website interface. It contains many thousands of user-contributed PKGBUILDs for software which is unavailable as an official Arch package. If you need to build a package outside the official Arch tree, chances are it is in the AUR.
 +
 
 +
{{Warning|Official PKGBUILDs assume that packages are [[DeveloperWiki:Building_in_a_Clean_Chroot|built in a clean chroot]]. Building software on a ''dirty'' build system may fail or cause unexpected behaviour at runtime, because if the build system detects dependencies dynamically, the result depends on what packages are available on the build system.}}
 +
 
 +
==== SVN tree ====
 +
 
 +
The ''core'', ''extra'', and ''testing'' [[repositories]] are in the ''packages'' SVN respository for [[#Non-recursive checkout|checkout]]. The ''community'' and ''multilib'' repositories are in the ''community'' SVN repository.
 +
 
 +
Each package has its own subdirectory. Within it there are {{ic|repos}} and {{ic|trunk}} directories. {{ic|repos}} is further broken down by repository name (e.g., ''core'') and architecture. PKGBUILD's and files found in {{ic|repos}} are used in official builds. Files found in {{ic|trunk}} are used by developers in preparation before being copied to {{ic|repos}}.
 +
 
 +
For example, the tree for {{pkg|acl}} looks like this:
 +
 
 +
acl
 +
acl/repos
 +
acl/repos/core-i686
 +
acl/repos/core-i686/PKGBUILD
 +
acl/repos/core-x86_64
 +
acl/repos/core-x86_64/PKGBUILD
 +
acl/trunk
 +
acl/trunk/PKGBUILD
 +
 
 +
The source code for the package is not present in the ABS directory. Instead, the {{ic|PKGBUILD}} contains a URL that will download the source code when the package is built.
  
 
== Why would I want to use ABS? ==
 
== Why would I want to use ABS? ==
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The Arch Build System is used to:
 
The Arch Build System is used to:
 
* Compile or recompile a package, for any reason
 
* Compile or recompile a package, for any reason
* Make and install new packages from source of software for which no packages are yet available (see [[Creating Packages]])  
+
* Make and install new packages from source of software for which no packages are yet available (see [[Creating packages]])  
 
* Customize existing packages to fit your needs (enabling or disabling options, patching)
 
* Customize existing packages to fit your needs (enabling or disabling options, patching)
* Rebuild your entire system using your compiler flags, "a la FreeBSD" (e.g. with [[pacbuilder]])
+
* Rebuild your entire system using your compiler flags, "à la FreeBSD" (e.g. with {{AUR|pacbuilder-svn}} (not available anymore))
* Cleanly build and install your own custom kernel (see [[Kernel Compilation]])
+
* Cleanly build and install your own custom kernel (see [[Kernels#Compilation|Kernel compilation]])
 
* Get kernel modules working with your custom kernel
 
* Get kernel modules working with your custom kernel
 
* Easily compile and install a newer, older, beta, or development version of an Arch package by editing the version number in the PKGBUILD
 
* Easily compile and install a newer, older, beta, or development version of an Arch package by editing the version number in the PKGBUILD
Line 71: Line 94:
 
== How to use ABS ==
 
== How to use ABS ==
  
Building packages using abs consists of these steps:
+
To retrieve the [[PKGBUILD]] required to build a certain package from source, you can either use [[Subversion|Svn]] or a [[Git]]-based approach using the {{pkg|asp}} package which is a thin wrapper around the svntogit repositories. In the following, the svn-based method as well as the [[#Retrieve PKGBUILD source using Git|git-based method]] is described.
#Install the {{Pkg|abs}} package with [[pacman]].
 
#Run {{ic|abs}} as root to create the ABS tree by synchronizing it with the Arch Linux server.
 
#Copy the build files (usually residing under {{ic|/var/abs/<repo>/<pkgname>}}) to a build directory.
 
#Navigate to that directory, edit the PKGBUILD (if desired/necessary) and do '''makepkg'''.
 
#According to instructions in the PKGBUILD, makepkg will download the appropriate source tarball, unpack it, patch if desired, compile according to {{ic|CFLAGS}} specified in {{ic|makepkg.conf}}, and finally compress the built files into a package with the extension {{ic|.pkg.tar.gz}} or {{ic|.pkg.tar.xz}}.  
 
#Installing is as easy as doing {{ic|pacman -U <.pkg.tar.xz file>}}. Package removal is also handled by pacman.
 
  
=== Install tools ===
+
=== Retrieve PKGBUILD source using Svn ===
  
To use the ABS, you first need to install {{Pkg|abs}} from the [[Official Repositories|official repositories]]:
+
==== Prerequisites ====
  
# pacman -S abs
+
[[Install]] the {{Pkg|subversion}} package.
  
This will grab the abs-sync scripts, various build scripts, and [[rsync]] (as a dependency, if you do not already have it).
+
==== Non-recursive checkout ====
  
Before you can actually build anything, however, you will also need to grab basic compiling tools. These are handily collected in the package group '''base-devel'''. This group can be installed with:
+
{{Warning|Do not download the whole repository; only follow the instructions below. The entire SVN repository is huge. Not only will it take an obscene amount of disk space, but it will also tax the archlinux.org server for you to download it. If you abuse this service, your address may be blocked. Never use the public SVN for any sort of scripting.}}
  
# pacman -S base-devel
+
To checkout the ''core'', ''extra'', and ''testing'' [[repositories]]:
  
=== /etc/abs.conf ===
+
$ svn checkout --depth=empty <nowiki>svn://svn.archlinux.org/packages</nowiki>
  
As root, edit {{ic|/etc/abs.conf}} to include your desired repositories.
+
To checkout the ''community'' and ''multilib'' repositories:
  
Remove the {{ic|!}} in front of the appropriate repositories. For example:
+
  $ svn checkout --depth=empty <nowiki>svn://svn.archlinux.org/community</nowiki>
  REPOS=(core extra community !testing)
 
  
=== ABS tree ===
+
In both cases, it simply creates an empty directory, but it does know that it is an svn checkout.
  
The ABS tree is an SVN directory hierarchy located under {{ic|/var/abs}} and looks like this:
+
==== Checkout a package ====
  
{{bc|<nowiki>
+
In the directory containing the svn repository you checked out (i.e., ''packages'' or ''community''), do:
| -- core/
 
|    || -- acl/
 
|    ||    || -- PKGBUILD
 
|    || -- attr/
 
|    ||    || -- PKGBUILD
 
|    || -- abs/
 
|    ||    || -- PKGBUILD
 
|    || -- autoconf/
 
|    ||    || -- PKGBUILD
 
|    || -- ...
 
| -- extra/
 
|    || -- acpid/
 
|    ||    || -- PKGBUILD
 
|    || -- apache/
 
|    ||    || -- PKGBUILD
 
|    || -- ...
 
| -- community/
 
|    || -- ...
 
</nowiki>}}
 
  
The ABS tree has exactly the same structure as the package database:
+
$ svn update ''package-name''
  
* First-level: Reposistory name
+
This will pull the package you requested into your checkout. From now on, any time you ''svn update'' at the top level, this will be updated as well.
* Second-level: Package name directories
 
* Third level: PKGBUILD (contains information needed to build a package) and other related files (patches, other files needed for building the package)
 
  
The source code for the package is not present in the ABS directory. Instead, the '''PKGBUILD''' file contains a URL that will download the source code when the package is built. So the size of abs tree is quite small.
+
If you specify a package that does not exist, svn will not warn you. It will just print something like "At revision 115847", without creating any files.  If that happens:
 +
* check your spelling of the package name
 +
* check that the package has not been moved to another repository (i.e. from community to the main repository)
 +
* check https://www.archlinux.org/packages to see if the package is built from another base package (for example, {{Pkg|python-tensorflow}} is built from the {{Pkg|tensorflow}} PKGBUILD)
  
==== Download ABS tree ====
+
{{Tip|To checkout an older version of a package, see [[#Checkout an older version of a package]].}}
As root, run:
 
# abs
 
  
Your ABS tree is now created under {{ic|/var/abs}}. Note the appropriate branches of the ABS tree now exist and correspond to the ones you specified in {{ic|/etc/abs.conf}}.  
+
You should periodically update all of your checked out packages if you wish to perform rebuilds on more recent revisions of the repositories. To do so, do:
  
The abs command should be run periodically to keep in sync with the official repositories. Individual ABS package files can also be downloaded with:
+
$ svn update
  
# abs <repository>/<package>
+
=== Retrieve PKGBUILD source using Git ===
This way you do not have to check out the entire abs tree just to build one package.
 
  
=== /etc/makepkg.conf ===
+
As a precondition, [[install]] the {{Pkg|asp}} package.
  
{{ic|/etc/makepkg.conf}} specifies global environment variables and compiler flags which you may wish to edit if you are using an SMP system, or to specify other desired optimizations. The default settings are for i686 and x86_64 optimizations which will work fine for those architectures on single-CPU systems. (The defaults will work on SMP machines, but will only use one core/CPU when compiling -- see [[makepkg.conf]].)
+
To clone the svntogit-repository for a specific package, use:
 +
$ asp checkout ''pkgname''
  
==== Set the PACKAGER variable in /etc/makepkg.conf ====
+
This will clone the git repository for the given package into a directory named like the package.
  
Setting the PACKAGER variable in {{ic|/etc/makepkg.conf}} is an optional but ''highly recommended'' step.  It allows a "flag" to quickly identify which packages have been built and/or installed by YOU, not the official maintainer!  This is easily accomplished using '''expac''' available from the community repo:
+
To update the cloned git repository, run {{ic|asp update}} followed by {{ic|git pull}} inside the git repository.
  
===== Showing All Packages (including those from AUR) =====
+
Furthermore, you can use all other git commands to checkout an older version of the package or to track custom changes. For more information on git usage, see the [[git]] page.
$ grep myname /etc/makepkg.conf
 
PACKAGER="myname <myemail@myserver.com>"
 
  
$ expac "%n %p" | grep "myname" | column -t
+
If you just want to copy a snapshot of the current [[PKGBUILD]] for a specific package, use:
archey3 myname
+
  $ asp export ''pkgname''
binutils myname
 
gcc myname
 
gcc-libs myname
 
glibc myname
 
tar myname
 
 
 
===== Showing Only Packages Contained in Repos =====
 
 
 
This example only shows packages contained in the repos defined in {{ic|/etc/pacman.conf}}:
 
 
 
$ . /etc/makepkg.conf; grep -xvFf <(pacman -Qqm) <(expac "%n\t%p" | grep "$PACKAGER$" | cut -f1)
 
binutils
 
gcc
 
gcc-libs
 
glibc
 
tar
 
 
 
=== Create a build directory ===
 
 
 
It is recommended to create a build directory where the actual compiling will take place; you should never modify the ABS tree by building within it, as data will be lost (overwritten) on each ABS update. It is good practice to use your home directory, though some Arch users prefer to create a 'local' directory under {{ic|/var/abs/}}, owned by a normal user.
 
 
 
Create your build directory. e.g.:
 
 
 
  $ mkdir -p $HOME/abs
 
 
 
Copy the ABS from the tree ({{ic|/var/abs/<repository>/<pkgname>}}) to the build directory.
 
  
 
=== Build package ===
 
=== Build package ===
  
In our example, we will build the ''slim'' display manager package.
+
See [[makepkg#Configuration]] on how to configure ''makepkg'' for building packages from the [[PKGBUILD]]'s you have checked out.
 
 
Copy the slim ABS from the ABS tree to a build directory:
 
$ cp -r /var/abs/extra/slim/ ~/abs
 
 
 
Navigate to the build directory:
 
$ cd ~/abs/slim
 
 
 
Modify the PKGBUILD to add or remove support for components, to patch or to change package versions, etc. (optional):
 
$ nano PKGBUILD
 
 
 
Run makepkg as normal user (with {{ic|-s}} switch to install with automatic dependency handling):
 
$ makepkg -s
 
 
 
{{Note|Before complaining about missing (make) dependencies, remember that the {{Grp|base}} group is assumed to be installed on all Arch Linux systems. The group "base-devel" is assumed to be installed when building with '''makepkg'''. See [[#Install tools]].}}
 
  
Install as root:
+
Then, copy the directory containing the [[PKGBUILD]] you wish to modify to a new location. There, make the desired modifications and use ''makepkg'' there as described in [[makepkg#Usage]] to create and install the new package.
# pacman -U slim-1.3.0-2-i686.pkg.tar.xz
 
  
That's it. You have just built slim from source and cleanly installed it to your system with pacman. Package removal is also handled by pacman with {{ic|pacman -R slim}}.
+
== Tips and tricks ==
  
The ABS method adds a level of convenience and automation, while still maintaining complete transparency and control of the build and installation functions by including them in the PKGBUILD.
+
=== Preserve modified packages ===
  
==== fakeroot ====
+
Updating the system with pacman will replace a modified package from ABS with the package of the same name from the official repositories. See the following instructions for how to avoid this.
Essentially, the same steps are being executed in the traditional method (generally including the {{ic|./configure, make, make install}} steps) but the software is installed into a ''fake root'' environment. (A ''fake root'' is simply a subdirectory within the build directory that functions and behaves as the system's root directory. In conjunction with the '''fakeroot''' program, makepkg creates a fake root directory, and installs the compiled binaries and associated files into it, with '''root''' as owner.) The ''fake root'', or subdirectory tree containing the compiled software, is then compressed into an archive with the extension {{ic|.pkg.tar.xz}}, or a ''package''. When invoked, pacman then extracts the package (installs it) into the system's real root directory ({{ic|/}}).
 
  
== Traditional method of compiling software, without ABS ==
+
Insert a group array into the PKGBUILD, and add the package to a group called {{ic|modified}}.
  
If you are not familiar with manually compiling software from source, you should know that most packages (but not all) can be built from source in this '''traditional way''':
+
{{hc|PKGBUILD|2=
 +
groups=('modified')
 +
}}
  
* Download source tarball from remote server, using web browser, ftp, wget or alternate method.
+
Add this group to the section {{ic|IgnoreGroup}} in {{ic|/etc/pacman.conf}}.
  
* Decompress the source file:
+
{{hc|/etc/pacman.conf|2=
$ tar -xzf foo-0.99.tar.gz
+
IgnoreGroup = modified
or
+
}}
$ tar -xjf foo-0.99.tar.bz2
 
  
* Enter the directory:
+
If new versions are available in the official repositories during a system update, pacman prints a note that it is skipping this update because it is in the IgnoreGroup section. At this point the modified package should be rebuilt from ABS to avoid partial upgrades.
$ cd foo-0.99
 
  
* Configure the package. Generally, there is a script called {{ic|configure}} in the source directory that is used to configure the package (add or remove support for things, choose the install destination, etc.) and check that your computer has all the software needed by the package. It can be run by:
+
=== Checkout an older version of a package ===
$ ./configure ''options''
 
  
You should first try the help to better understand how it works:
+
Within the svn repository you checked out as described in [[#Non-recursive checkout]] (i.e. "packages" or "community"), first examine the log:
$ ./configure --help
 
  
If a {{ic|--prefix}} option is not passed to the script, ''most'' scripts will use {{ic|/usr/local}} as the install path, but others will use {{ic|/usr}}. For the sake of consistency, it is generally advised to pass the {{ic|1=--prefix=/usr/local}} option. It is good practice, as per [[Filesystem_Hierarchy_Standard|FHS]], to install personal programs in {{ic|/usr/local}}, and to have the ones being managed by the distro in {{ic|/usr}}. This ensures personal program versions can coexist with those being managed by the distro's package manager &mdash; in Arch's case, [[pacman]].
+
$ svn log ''package-name''
$ ./configure --prefix=/usr/local
 
  
* Compile the sources:
+
Find out the revision you want by examining the history, then specify the revision you wish to checkout. For example, to checkout revision {{ic|r1729}} you would do:
  
  $ make
+
  $ svn update -r1729 ''package-name''
  
* Install:
+
This will update an existing working copy of ''package-name'' to the chosen revision.
  
# make install
+
You can also specify a date. If no revision on that day exists, svn will grab the most recent package before that time. The following example checks out the revision from 2009-03-03:
  
* Removal would be accomplished by entering the source directory and running:
+
$ svn update -r{20090303} ''package-name''
  
# make uninstall
+
It is possible to checkout packages at versions before they were moved to another repository as well; check the logs thoroughly for the date they were moved or the last revision number.
  
However, you should always read the {{ic|INSTALL}} file to know how the package should be built and installed! '''Not all packages use the {{ic|configure; make; make install}} system!'''
+
== Other tools ==
  
{{Note | The above traditional method of compiling source tarballs can, of course, still be used on Arch Linux. However, if you are not careful, files may become scattered throughout the filesystem that pacman (or any other package manager) will be unaware of. You should only use this method if you are experienced at manual compilation and system software tracking, as it can lead to future problems on Arch (or any distribution) if using a package manager.}}
+
* [http://xyne.archlinux.ca/projects/pbget/ pbget] - retrieve PKGBUILDs for individual packages directly from the web interface. Includes AUR support.
 +
* [https://github.com/falconindy/asp asp] - a tool to manage the build source files used to create Arch Linux packages. Uses the git interface which offers more up to date sources.

Latest revision as of 08:41, 24 September 2017

This article provides an overview of the Arch Build System (ABS) along with a walkthrough for beginners. It is not intended to be a complete reference guide.

What is the Arch Build System?

The Arch Build System is a ports-like system for building and packaging software from source code. While pacman is the specialized Arch tool for binary package management (including packages built with the ABS), ABS is a collection of tools for compiling source into installable .pkg.tar.xz packages.

What is a ports-like system?

Ports is a system used by *BSD to automate the process of building software from source code. The system uses a port to download, unpack, patch, compile, and install the given software. A port is merely a small directory on the user's computer, named after the corresponding software to be installed, that contains a few files with the instructions for building and installing the software from source. This makes installing software as simple as typing make or make install clean within the port's directory.

ABS is a similar concept

ABS is made up of a directory tree that can be checked out using SVN. This tree represents, but does not contain, all official Arch software. Subdirectories do not contain the software package nor the source but rather a PKGBUILD file and sometimes other files. By issuing makepkg inside a directory containing a PKGBUILD, the software is first compiled and then packaged within the build directory. Then you can use pacman to install or upgrade your new package.

ABS overview

'ABS' may be used as an umbrella term since it includes and relies on several other components; therefore, though not technically accurate, 'ABS' can refer to the following tools as a complete toolkit:

SVN tree
The directory structure containing files needed to build all official packages but not the packages themselves nor the source files of the software. It is available in svn and git repositories.
PKGBUILD
A Bash script that contains the URL of the source code along with the compilation and packaging instructions.
makepkg
shell command tool which reads the PKGBUILDs, automatically downloads and compiles the sources and creates a .pkg.tar* according to the PKGEXT array in makepkg.conf. You may also use makepkg to make your own custom packages from the AUR or third-party sources. See Creating packages for more information.
pacman
pacman is completely separate, but is necessarily invoked either by makepkg or manually, to install and remove the built packages and for fetching dependencies.
AUR
The Arch User Repository is separate from ABS but AUR (unsupported) PKGBUILDs are built using makepkg to compile and package up software. In contrast to the ABS tree on your local machine, the AUR exists as a website interface. It contains many thousands of user-contributed PKGBUILDs for software which is unavailable as an official Arch package. If you need to build a package outside the official Arch tree, chances are it is in the AUR.
Warning: Official PKGBUILDs assume that packages are built in a clean chroot. Building software on a dirty build system may fail or cause unexpected behaviour at runtime, because if the build system detects dependencies dynamically, the result depends on what packages are available on the build system.

SVN tree

The core, extra, and testing repositories are in the packages SVN respository for checkout. The community and multilib repositories are in the community SVN repository.

Each package has its own subdirectory. Within it there are repos and trunk directories. repos is further broken down by repository name (e.g., core) and architecture. PKGBUILD's and files found in repos are used in official builds. Files found in trunk are used by developers in preparation before being copied to repos.

For example, the tree for acl looks like this:

acl
acl/repos
acl/repos/core-i686
acl/repos/core-i686/PKGBUILD
acl/repos/core-x86_64
acl/repos/core-x86_64/PKGBUILD
acl/trunk
acl/trunk/PKGBUILD

The source code for the package is not present in the ABS directory. Instead, the PKGBUILD contains a URL that will download the source code when the package is built.

Why would I want to use ABS?

The Arch Build System is used to:

  • Compile or recompile a package, for any reason
  • Make and install new packages from source of software for which no packages are yet available (see Creating packages)
  • Customize existing packages to fit your needs (enabling or disabling options, patching)
  • Rebuild your entire system using your compiler flags, "à la FreeBSD" (e.g. with pacbuilder-svnAUR (not available anymore))
  • Cleanly build and install your own custom kernel (see Kernel compilation)
  • Get kernel modules working with your custom kernel
  • Easily compile and install a newer, older, beta, or development version of an Arch package by editing the version number in the PKGBUILD

ABS is not necessary to use Arch Linux, but it is useful for automating certain tasks of source compilation.

How to use ABS

To retrieve the PKGBUILD required to build a certain package from source, you can either use Svn or a Git-based approach using the asp package which is a thin wrapper around the svntogit repositories. In the following, the svn-based method as well as the git-based method is described.

Retrieve PKGBUILD source using Svn

Prerequisites

Install the subversion package.

Non-recursive checkout

Warning: Do not download the whole repository; only follow the instructions below. The entire SVN repository is huge. Not only will it take an obscene amount of disk space, but it will also tax the archlinux.org server for you to download it. If you abuse this service, your address may be blocked. Never use the public SVN for any sort of scripting.

To checkout the core, extra, and testing repositories:

$ svn checkout --depth=empty svn://svn.archlinux.org/packages

To checkout the community and multilib repositories:

$ svn checkout --depth=empty svn://svn.archlinux.org/community

In both cases, it simply creates an empty directory, but it does know that it is an svn checkout.

Checkout a package

In the directory containing the svn repository you checked out (i.e., packages or community), do:

$ svn update package-name

This will pull the package you requested into your checkout. From now on, any time you svn update at the top level, this will be updated as well.

If you specify a package that does not exist, svn will not warn you. It will just print something like "At revision 115847", without creating any files. If that happens:

  • check your spelling of the package name
  • check that the package has not been moved to another repository (i.e. from community to the main repository)
  • check https://www.archlinux.org/packages to see if the package is built from another base package (for example, python-tensorflow is built from the tensorflow PKGBUILD)
Tip: To checkout an older version of a package, see #Checkout an older version of a package.

You should periodically update all of your checked out packages if you wish to perform rebuilds on more recent revisions of the repositories. To do so, do:

$ svn update

Retrieve PKGBUILD source using Git

As a precondition, install the asp package.

To clone the svntogit-repository for a specific package, use:

$ asp checkout pkgname

This will clone the git repository for the given package into a directory named like the package.

To update the cloned git repository, run asp update followed by git pull inside the git repository.

Furthermore, you can use all other git commands to checkout an older version of the package or to track custom changes. For more information on git usage, see the git page.

If you just want to copy a snapshot of the current PKGBUILD for a specific package, use:

$ asp export pkgname

Build package

See makepkg#Configuration on how to configure makepkg for building packages from the PKGBUILD's you have checked out.

Then, copy the directory containing the PKGBUILD you wish to modify to a new location. There, make the desired modifications and use makepkg there as described in makepkg#Usage to create and install the new package.

Tips and tricks

Preserve modified packages

Updating the system with pacman will replace a modified package from ABS with the package of the same name from the official repositories. See the following instructions for how to avoid this.

Insert a group array into the PKGBUILD, and add the package to a group called modified.

PKGBUILD
groups=('modified')

Add this group to the section IgnoreGroup in /etc/pacman.conf.

/etc/pacman.conf
IgnoreGroup = modified

If new versions are available in the official repositories during a system update, pacman prints a note that it is skipping this update because it is in the IgnoreGroup section. At this point the modified package should be rebuilt from ABS to avoid partial upgrades.

Checkout an older version of a package

Within the svn repository you checked out as described in #Non-recursive checkout (i.e. "packages" or "community"), first examine the log:

$ svn log package-name

Find out the revision you want by examining the history, then specify the revision you wish to checkout. For example, to checkout revision r1729 you would do:

$ svn update -r1729 package-name

This will update an existing working copy of package-name to the chosen revision.

You can also specify a date. If no revision on that day exists, svn will grab the most recent package before that time. The following example checks out the revision from 2009-03-03:

$ svn update -r{20090303} package-name

It is possible to checkout packages at versions before they were moved to another repository as well; check the logs thoroughly for the date they were moved or the last revision number.

Other tools

  • pbget - retrieve PKGBUILDs for individual packages directly from the web interface. Includes AUR support.
  • asp - a tool to manage the build source files used to create Arch Linux packages. Uses the git interface which offers more up to date sources.