The Buildroot user manual


Table of Contents

1. About Buildroot
2. Starting up
2.1. System requirements
2.1.1. Mandatory packages
2.1.2. Optional packages
2.2. Getting Buildroot
2.3. Using Buildroot
3. Working with Buildroot
3.1. Details on Buildroot configuration
3.1.1. Cross-compilation toolchain
3.1.2. /dev management
3.1.3. init system
3.2. make tips
3.3. Customization
3.3.1. Customizing the generated target filesystem
3.3.2. Customizing the BusyBox configuration
3.3.3. Customizing the uClibc configuration
3.3.4. Customizing the Linux kernel configuration
3.3.5. Customizing the toolchain
3.4. Storing the configuration
3.4.1. Basics for storing the configuration
3.4.2. Creating your own board support
3.4.3. Step-by-step instructions for storing configuration
3.4.4. Customizing packages
3.4.5. Keeping customizations outside Buildroot
3.5. Daily use
3.5.1. Understanding when a full rebuild is necessary
3.5.2. Understanding how to rebuild packages
3.5.3. Offline builds
3.5.4. Building out-of-tree
3.5.5. Environment variables
3.5.6. Dealing efficiently with filesystem images
3.5.7. Graphing the dependencies between packages
3.5.8. Graphing the build duration
3.6. Integration with Eclipse
3.7. Hacking Buildroot
4. Frequently Asked Questions & Troubleshooting
4.1. The boot hangs after Starting network…
4.2. Why is there no compiler on the target?
4.3. Why are there no development files on the target?
4.4. Why is there no documentation on the target?
4.5. Why are some packages not visible in the Buildroot config menu?
4.6. Why not use the target directory as a chroot directory?
4.7. Why doesn’t Buildroot generate binary packages (.deb, .ipkg…)?
5. Known issues
6. Going further in Buildroot’s innards
6.1. How Buildroot works
6.2. Advanced usage
6.2.1. Using the generated toolchain outside Buildroot
6.2.2. Using gdb in Buildroot
6.2.3. Using ccache in Buildroot
6.2.4. Location of downloaded packages
6.2.5. Package-specific make targets
6.2.6. Using Buildroot during development
7. Developer Guidelines
7.1. Coding style
7.1.1. Config.in file
7.1.2. The .mk file
7.1.3. The documentation
7.2. Adding new packages to Buildroot
7.2.1. Package directory
7.2.2. Config.in file
7.2.3. The .mk file
7.2.4. The .hash file
7.2.5. Infrastructure for packages with specific build systems
7.2.6. Infrastructure for autotools-based packages
7.2.7. Infrastructure for CMake-based packages
7.2.8. Infrastructure for Python packages
7.2.9. Infrastructure for LuaRocks-based packages
7.2.10. Infrastructure for Perl/CPAN packages
7.2.11. Infrastructure for virtual packages
7.2.12. Hooks available in the various build steps
7.2.13. Gettext integration and interaction with packages
7.2.14. Tips and tricks
7.2.15. Conclusion
7.3. Patching a package
7.3.1. Providing patches
7.3.2. How patches are applied
7.3.3. Format and licensing of the package patches
7.3.4. Integrating patches found on the Web
7.4. Download infrastructure
7.5. Debugging Buildroot
8. Legal notice and licensing
8.1. Complying with open source licenses
8.2. License abbreviations
8.3. Complying with the Buildroot license
9. Beyond Buildroot
9.1. Boot the generated images
9.1.1. NFS boot
9.2. Chroot
10. Getting involved
10.1. Mailing List
10.1.1. Subscribing to the mailing list
10.1.2. Searching the List Archives
10.2. IRC
10.3. Patchwork
10.3.1. Applying Patches from Patchwork
10.4. Bugtracker
10.5. Buildroot wikipage
10.6. Events
10.6.1. Buildroot Developer Days aside ELC-E 2012 (November 3-4, 2012 - Barcelona)
10.6.2. Buildroot presentation at LSM 2012 (July 12-14, 2012 - Geneva)
10.6.3. Buildroot Developer Days aside FOSDEM 2012 (February 3, 2012 - Brussels)
11. Contributing to Buildroot
11.1. Reproducing, analyzing and fixing bugs
11.2. Analyzing and fixing autobuild failures
11.3. Reviewing and testing patches
11.4. Work on items from the TODO list
11.5. Submitting patches
11.5.1. Cover letter
11.5.2. Patch revision changelog
11.6. Reporting issues/bugs or getting help
12. Appendix
12.1. Makedev syntax documentation
12.2. Makeuser syntax documentation
12.3. List of target packages available in Buildroot
12.4. List of virtual packages
12.5. List of host utilities available in Buildroot
12.6. Deprecated features

List of Examples

7.1. Config script: divine package
7.2. Config script: imagemagick package:

Buildroot 2014.08 manual generated on 2014-07-25 06:17:07 CEST from git revision adceeca

The Buildroot manual is written by the Buildroot developers. It is licensed under the GNU General Public License, version 2. Refer to the COPYING file in the Buildroot sources for the full text of this license.

Copyright © 2004-2014 The Buildroot developers

logo.png

Chapter 1. About Buildroot

Buildroot is a tool that simplifies and automates the process of building a complete Linux system for an embedded system, using cross-compilation.

In order to achieve this, Buildroot is able to generate a cross-compilation toolchain, a root filesystem, a Linux kernel image and a bootloader for your target. Buildroot can be used for any combination of these options, independently (you can for example use an existing cross-compilation toolchain, and build only your root filesystem with Buildroot).

Buildroot is useful mainly for people working with embedded systems. Embedded systems often use processors that are not the regular x86 processors everyone is used to having in his PC. They can be PowerPC processors, MIPS processors, ARM processors, etc.

Buildroot supports numerous processors and their variants; it also comes with default configurations for several boards available off-the-shelf. Besides this, a number of third-party projects are based on, or develop their BSP [1] or SDK [2] on top of Buildroot.



[1] BSP: Board Support Package

[2] SDK: Software Development Kit

Chapter 2. Starting up

2.1. System requirements

Buildroot is designed to run on Linux systems.

Buildroot needs some software to be already installed on the host system; here are the lists of the mandatory and optional packages (package names may vary between distributions).

Take care to install both runtime and development data, especially for the libraries that may be packaged in 2 distinct packages.

2.1.1. Mandatory packages

  • Build tools:

    • which
    • sed
    • make (version 3.81 or any later)
    • binutils
    • build-essential (only for Debian based systems)
    • gcc (version 2.95 or any later)
    • g++ (version 2.95 or any later)
    • bash
    • patch
    • gzip
    • bzip2
    • perl (version 5.8.7 or any later)
    • tar
    • cpio
    • python (version 2.6 or 2.7)
    • unzip
    • rsync
  • Source fetching tools:

    • wget

2.1.2. Optional packages

  • Source fetching tools:

    In the official tree, most of the package sources are retrieved using wget; a few are only available through their git, mercurial, svn or cvs repository.

    All other source fetching methods are implemented and may be used in a development context (further details: refer to Section 7.4, “Download infrastructure”).

    • bazaar
    • cvs
    • git
    • mercurial
    • rsync
    • scp
    • subversion
  • Configuration interface dependencies (requires development libraries):

    • ncurses5 to use the menuconfig interface
    • qt4 to use the xconfig interface
    • glib2, gtk2 and glade2 to use the gconfig interface
  • Java-related packages, if the Java Classpath needs to be built for the target system:

    • The javac compiler
    • The jar tool
  • Documentation generation tools:

    • asciidoc, version 8.6.3 or higher
    • w3m
    • python with the argparse module (automatically present in 2.7+ and 3.2+)
    • dblatex (required for the pdf manual only)
  • Graph generation tools:

    • graphviz to use graph-depends and <pkg>-graph-depends
    • python-matplotlib to use graph-build

2.2. Getting Buildroot

Buildroot releases are made approximately every 3 months. Direct Git access and daily snapshots are also available, if you want more bleeding edge.

Releases are available at http://buildroot.net/downloads/.

The latest snapshot is always available at http://buildroot.net/downloads/snapshots/buildroot-snapshot.tar.bz2, and previous snapshots are also available at http://buildroot.net/downloads/snapshots/.

To download Buildroot using Git, you can simply follow the rules described on the "Accessing Git" page (http://buildroot.net/git.html) of the Buildroot website (http://buildroot.net). For the impatient, here’s a quick recipe:

 $ git clone git://git.buildroot.net/buildroot

2.3. Using Buildroot

Buildroot has a nice configuration tool similar to the one you can find in the Linux kernel or in BusyBox. Note that you can and should build everything as a normal user. There is no need to be root to configure and use Buildroot. The first step is to run the configuration assistant:

 $ make menuconfig

or

 $ make nconfig

to run the old or new curses-based configurator, or

 $ make xconfig

or

 $ make gconfig

to run the Qt or GTK-based configurators.

All of these "make" commands will need to build a configuration utility (including the interface), so you may need to install "development" packages for relevant libraries used by the configuration utilities. Check Section 2.1, “System requirements” to know what Buildroot needs, and specifically the optional requirements Section 2.1.2, “Optional packages” to get the dependencies of your favorite interface.

For each menu entry in the configuration tool, you can find associated help that describes the purpose of the entry.

Once everything is configured, the configuration tool generates a .config file that contains the description of your configuration. It will be used by the Makefiles to do what’s needed.

Let’s go:

 $ make

You should never use make -jN with Buildroot: it does not support top-level parallel make. Instead, use the BR2_JLEVEL option to tell Buildroot to run each package compilation with make -jN.

The make command will generally perform the following steps:

  • download source files (as required);
  • configure, build and install the cross-compiling toolchain using the appropriate toolchain backend, or simply import an external toolchain;
  • build/install selected target packages;
  • build a kernel image, if selected;
  • build a bootloader image, if selected;
  • create a root filesystem in selected formats.

Buildroot output is stored in a single directory, output/. This directory contains several subdirectories:

  • images/ where all the images (kernel image, bootloader and root filesystem images) are stored.
  • build/ where all the components are built (this includes tools needed to run Buildroot on the host and packages compiled for the target). The build/ directory contains one subdirectory for each of these components.
  • staging/ which contains a hierarchy similar to a root filesystem hierarchy. This directory contains the installation of the cross-compilation toolchain and all the userspace packages selected for the target. However, this directory is not intended to be the root filesystem for the target: it contains a lot of development files, unstripped binaries and libraries that make it far too big for an embedded system. These development files are used to compile libraries and applications for the target that depend on other libraries.
  • target/ which contains almost the complete root filesystem for the target: everything needed is present except the device files in /dev/ (Buildroot can’t create them because Buildroot doesn’t run as root and doesn’t want to run as root). Also, it doesn’t have the correct permissions (e.g. setuid for the busybox binary). Therefore, this directory should not be used on your target. Instead, you should use one of the images built in the images/ directory. If you need an extracted image of the root filesystem for booting over NFS, then use the tarball image generated in images/ and extract it as root. Compared to staging/, target/ contains only the files and libraries needed to run the selected target applications: the development files (headers, etc.) are not present, the binaries are stripped.
  • host/ contains the installation of tools compiled for the host that are needed for the proper execution of Buildroot, including the cross-compilation toolchain.

These commands, make menuconfig|nconfig|gconfig|xconfig and make, are the basic ones that allow to easily and quickly generate images fitting your needs, with all the supports and applications you enabled.

More details about the "make" command usage are given in Section 3.2, “make tips”.

Chapter 3. Working with Buildroot

This section explains how you can customize Buildroot to fit your needs.

3.1. Details on Buildroot configuration

All the configuration options in make *config have a help text providing details about the option. However, a number of topics require additional details that cannot easily be covered in the help text and are there covered in the following sections.

3.1.1. Cross-compilation toolchain

A compilation toolchain is the set of tools that allows you to compile code for your system. It consists of a compiler (in our case, gcc), binary utils like assembler and linker (in our case, binutils) and a C standard library (for example GNU Libc, uClibc).

The system installed on your development station certainly already has a compilation toolchain that you can use to compile an application that runs on your system. If you’re using a PC, your compilation toolchain runs on an x86 processor and generates code for an x86 processor. Under most Linux systems, the compilation toolchain uses the GNU libc (glibc) as the C standard library. This compilation toolchain is called the "host compilation toolchain". The machine on which it is running, and on which you’re working, is called the "host system" [3].

The compilation toolchain is provided by your distribution, and Buildroot has nothing to do with it (other than using it to build a cross-compilation toolchain and other tools that are run on the development host).

As said above, the compilation toolchain that comes with your system runs on and generates code for the processor in your host system. As your embedded system has a different processor, you need a cross-compilation toolchain - a compilation toolchain that runs on your host system but generates code for your target system (and target processor). For example, if your host system uses x86 and your target system uses ARM, the regular compilation toolchain on your host runs on x86 and generates code for x86, while the cross-compilation toolchain runs on x86 and generates code for ARM.

Buildroot provides two solutions for the cross-compilation toolchain:

  • The internal toolchain backend, called Buildroot toolchain in the configuration interface.
  • The external toolchain backend, called External toolchain in the configuration interface.

The choice between these two solutions is done using the Toolchain Type option in the Toolchain menu. Once one solution has been chosen, a number of configuration options appear, they are detailed in the following sections.

Internal toolchain backend

The internal toolchain backend is the backend where Buildroot builds by itself a cross-compilation toolchain, before building the userspace applications and libraries for your target embedded system.

This backend supports several C libraries: uClibc, the glibc and eglibc.

Once you have selected this backend, a number of options appear. The most important ones allow to:

  • Change the version of the Linux kernel headers used to build the toolchain. This item deserves a few explanations. In the process of building a cross-compilation toolchain, the C library is being built. This library provides the interface between userspace applications and the Linux kernel. In order to know how to "talk" to the Linux kernel, the C library needs to have access to the Linux kernel headers (i.e. the .h files from the kernel), which define the interface between userspace and the kernel (system calls, data structures, etc.). Since this interface is backward compatible, the version of the Linux kernel headers used to build your toolchain do not need to match exactly the version of the Linux kernel you intend to run on your embedded system. They only need to have a version equal or older to the version of the Linux kernel you intend to run. If you use kernel headers that are more recent than the Linux kernel you run on your embedded system, then the C library might be using interfaces that are not provided by your Linux kernel.
  • Change the version of the GCC compiler, binutils and the C library.
  • Select a number of toolchain options (uClibc only): whether the toolchain should have largefile support (i.e. support for files larger than 2 GB on 32 bits systems), IPv6 support, RPC support (used mainly for NFS), wide-char support, locale support (for internationalization), C++ support or thread support. Depending on which options you choose, the number of userspace applications and libraries visible in Buildroot menus will change: many applications and libraries require certain toolchain options to be enabled. Most packages show a comment when a certain toolchain option is required to be able to enable those packages. If needed, you can further refine the uClibc configuration by running make uclibc-menuconfig. Note however that all packages in Buildroot are tested against the default uClibc configuration bundled in Buildroot: if you deviate from this configuration by removing features from uClibc, some packages may no longer build.

It is worth noting that whenever one of those options is modified, then the entire toolchain and system must be rebuilt. See Section 3.5.1, “Understanding when a full rebuild is necessary”.

Advantages of this backend:

  • Well integrated with Buildroot
  • Fast, only builds what’s necessary

Drawbacks of this backend:

  • Rebuilding the toolchain is needed when doing make clean, which takes time. If you’re trying to reduce your build time, consider using the External toolchain backend.

External toolchain backend

The external toolchain backend allows to use existing pre-built cross-compilation toolchains. Buildroot knows about a number of well-known cross-compilation toolchains (from Linaro for ARM, Sourcery CodeBench for ARM, x86, x86-64, PowerPC, MIPS and SuperH, Blackfin toolchains from Analog Devices, etc.) and is capable of downloading them automatically, or it can be pointed to a custom toolchain, either available for download or installed locally.

Then, you have three solutions to use an external toolchain:

  • Use a predefined external toolchain profile, and let Buildroot download, extract and install the toolchain. Buildroot already knows about a few CodeSourcery, Linaro, Blackfin and Xilinx toolchains. Just select the toolchain profile in Toolchain from the available ones. This is definitely the easiest solution.
  • Use a predefined external toolchain profile, but instead of having Buildroot download and extract the toolchain, you can tell Buildroot where your toolchain is already installed on your system. Just select the toolchain profile in Toolchain through the available ones, unselect Download toolchain automatically, and fill the Toolchain path text entry with the path to your cross-compiling toolchain.
  • Use a completely custom external toolchain. This is particularly useful for toolchains generated using crosstool-NG or with Buildroot itself. To do this, select the Custom toolchain solution in the Toolchain list. You need to fill the Toolchain path, Toolchain prefix and External toolchain C library options. Then, you have to tell Buildroot what your external toolchain supports. If your external toolchain uses the glibc library, you only have to tell whether your toolchain supports C++ or not and whether it has built-in RPC support. If your external toolchain uses the uClibc library, then you have to tell Buildroot if it supports largefile, IPv6, RPC, wide-char, locale, program invocation, threads and C++. At the beginning of the execution, Buildroot will tell you if the selected options do not match the toolchain configuration.

Our external toolchain support has been tested with toolchains from CodeSourcery and Linaro, toolchains generated by crosstool-NG, and toolchains generated by Buildroot itself. In general, all toolchains that support the sysroot feature should work. If not, do not hesitate to contact the developers.

We do not support toolchains or SDK generated by OpenEmbedded or Yocto, because these toolchains are not pure toolchains (i.e. just the compiler, binutils, the C and C++ libraries). Instead these toolchains come with a very large set of pre-compiled libraries and programs. Therefore, Buildroot cannot import the sysroot of the toolchain, as it would contain hundreds of megabytes of pre-compiled libraries that are normally built by Buildroot.

We also do not support using the distribution toolchain (i.e. the gcc/binutils/C library installed by your distribution) as the toolchain to build software for the target. This is because your distribution toolchain is not a "pure" toolchain (i.e. only with the C/C++ library), so we cannot import it properly into the Buildroot build environment. So even if you are building a system for a x86 or x86_64 target, you have to generate a cross-compilation toolchain with Buildroot or crosstool-NG.

If you want to generate a custom toolchain for your project, that can be used as an external toolchain in Buildroot, our recommendation is definitely to build it with crosstool-NG. We recommend to build the toolchain separately from Buildroot, and then import it in Buildroot using the external toolchain backend.

Advantages of this backend:

  • Allows to use well-known and well-tested cross-compilation toolchains.
  • Avoids the build time of the cross-compilation toolchain, which is often very significant in the overall build time of an embedded Linux system.
  • Not limited to uClibc: glibc and eglibc toolchains are supported.

Drawbacks of this backend:

  • If your pre-built external toolchain has a bug, may be hard to get a fix from the toolchain vendor, unless you build your external toolchain by yourself using Crosstool-NG.

3.1.2. /dev management

On a Linux system, the /dev directory contains special files, called device files, that allow userspace applications to access the hardware devices managed by the Linux kernel. Without these device files, your userspace applications would not be able to use the hardware devices, even if they are properly recognized by the Linux kernel.

Under System configuration, /dev management, Buildroot offers four different solutions to handle the /dev directory :

  • The first solution is Static using device table. This is the old classical way of handling device files in Linux. With this method, the device files are persistently stored in the root filesystem (i.e. they persist across reboots), and there is nothing that will automatically create and remove those device files when hardware devices are added or removed from the system. Buildroot therefore creates a standard set of device files using a device table, the default one being stored in system/device_table_dev.txt in the Buildroot source code. This file is processed when Buildroot generates the final root filesystem image, and the device files are therefore not visible in the output/target directory. The BR2_ROOTFS_STATIC_DEVICE_TABLE option allows to change the default device table used by Buildroot, or to add an additional device table, so that additional device files are created by Buildroot during the build. So, if you use this method, and a device file is missing in your system, you can for example create a board/<yourcompany>/<yourproject>/device_table_dev.txt file that contains the description of your additional device files, and then you can set BR2_ROOTFS_STATIC_DEVICE_TABLE to system/device_table_dev.txt board/<yourcompany>/<yourproject>/device_table_dev.txt. For more details about the format of the device table file, see Section 12.1, “Makedev syntax documentation”.
  • The second solution is Dynamic using devtmpfs only. devtmpfs is a virtual filesystem inside the Linux kernel that has been introduced in kernel 2.6.32 (if you use an older kernel, it is not possible to use this option). When mounted in /dev, this virtual filesystem will automatically make device files appear and disappear as hardware devices are added and removed from the system. This filesystem is not persistent across reboots: it is filled dynamically by the kernel. Using devtmpfs requires the following kernel configuration options to be enabled: CONFIG_DEVTMPFS and CONFIG_DEVTMPFS_MOUNT. When Buildroot is in charge of building the Linux kernel for your embedded device, it makes sure that those two options are enabled. However, if you build your Linux kernel outside of Buildroot, then it is your responsibility to enable those two options (if you fail to do so, your Buildroot system will not boot).
  • The third solution is Dynamic using mdev. This method also relies on the devtmpfs virtual filesystem detailed above (so the requirement to have CONFIG_DEVTMPFS and CONFIG_DEVTMPFS_MOUNT enabled in the kernel configuration still apply), but adds the mdev userspace utility on top of it. mdev is a program part of BusyBox that the kernel will call every time a device is added or removed. Thanks to the /etc/mdev.conf configuration file, mdev can be configured to for example, set specific permissions or ownership on a device file, call a script or application whenever a device appears or disappear, etc. Basically, it allows userspace to react on device addition and removal events. mdev can for example be used to automatically load kernel modules when devices appear on the system. mdev is also important if you have devices that require a firmware, as it will be responsible for pushing the firmware contents to the kernel. mdev is a lightweight implementation (with fewer features) of udev. For more details about mdev and the syntax of its configuration file, see http://git.busybox.net/busybox/tree/docs/mdev.txt.
  • The fourth solution is Dynamic using eudev. This method also relies on the devtmpfs virtual filesystem detailed above, but adds the eudev userspace daemon on top of it. eudev is a daemon that runs in the background, and gets called by the kernel when a device gets added or removed from the system. It is a more heavyweight solution than mdev, but provides higher flexibility. eudev is a standalone version of udev, the original userspace daemon used in most desktop Linux distributions, which is now part of Systemd. For more details, see http://en.wikipedia.org/wiki/Udev.

The Buildroot developers recommendation is to start with the Dynamic using devtmpfs only solution, until you have the need for userspace to be notified when devices are added/removed, or if firmwares are needed, in which case Dynamic using mdev is usually a good solution.

Note that if systemd is chosen as init system, /dev management will be performed by the udev program provided by systemd.

3.1.3. init system

The init program is the first userspace program started by the kernel (it carries the PID number 1), and is responsible for starting the userspace services and programs (for example: web server, graphical applications, other network servers, etc.).

Buildroot allows to use three different types of init systems, which can be chosen from System configuration, Init system:

  • The first solution is BusyBox. Amongst many programs, BusyBox has an implementation of a basic init program, which is sufficient for most embedded systems. Enabling the BR2_INIT_BUSYBOX will ensure BusyBox will build and install its init program. This is the default solution in Buildroot. The BusyBox init program will read the /etc/inittab file at boot to know what to do. The syntax of this file can be found in http://git.busybox.net/busybox/tree/examples/inittab (note that BusyBox inittab syntax is special: do not use a random inittab documentation from the Internet to learn about BusyBox inittab). The default inittab in Buildroot is stored in system/skeleton/etc/inittab. Apart from mounting a few important filesystems, the main job the default inittab does is to start the /etc/init.d/rcS shell script, and start a getty program (which provides a login prompt).
  • The second solution is systemV. This solution uses the old traditional sysvinit program, packed in Buildroot in package/sysvinit. This was the solution used in most desktop Linux distributions, until they switched to more recent alternatives such as Upstart or Systemd. sysvinit also works with an inittab file (which has a slightly different syntax than the one from BusyBox). The default inittab installed with this init solution is located in package/sysvinit/inittab.
  • The third solution is systemd. systemd is the new generation init system for Linux. It does far more than traditional init programs: aggressive parallelization capabilities, uses socket and D-Bus activation for starting services, offers on-demand starting of daemons, keeps track of processes using Linux control groups, supports snapshotting and restoring of the system state, etc. systemd will be useful on relatively complex embedded systems, for example the ones requiring D-Bus and services communicating between each other. It is worth noting that systemd brings a fairly big number of large dependencies: dbus, udev and more. For more details about systemd, see http://www.freedesktop.org/wiki/Software/systemd.

The solution recommended by Buildroot developers is to use the BusyBox init as it is sufficient for most embedded systems. systemd can be used for more complex situations.

3.2. make tips

This is a collection of tips that help you make the most of Buildroot.

Configuration searches: The make *config commands offer a search tool. Read the help message in the different frontend menus to know how to use it:

  • in menuconfig, the search tool is called by pressing /;
  • in xconfig, the search tool is called by pressing Ctrl + f.

The result of the search shows the help message of the matching items.

Display all commands executed by make: 

 $ make V=1 <target>

Display all available targets: 

 $ make help

Not all targets are always available, some settings in the .config file may hide some targets:

  • busybox-menuconfig only works when busybox is enabled;
  • linux-menuconfig and linux-savedefconfig only work when linux is enabled;
  • uclibc-menuconfig is only available when the uClibc C library is selected in the internal toolchain backend;
  • barebox-menuconfig and barebox-savedefconfig only work when the barebox bootloader is enabled.

Cleaning: Explicit cleaning is required when any of the architecture or toolchain configuration options are changed.

To delete all build products (including build directories, host, staging and target trees, the images and the toolchain):

 $ make clean

Generating the manual: The present manual sources are located in the docs/manual directory. To generate the manual:

 $ make manual-clean
 $ make manual

The manual outputs will be generated in output/docs/manual.

Notes

Resetting Buildroot for a new target: To delete all build products as well as the configuration:

 $ make distclean

Notes. If ccache is enabled, running make clean or distclean does not empty the compiler cache used by Buildroot. To delete it, refer to Section 6.2.3, “Using ccache in Buildroot”.

3.3. Customization

3.3.1. Customizing the generated target filesystem

Besides changing one or another configuration through make *config, there are a few ways to customize the resulting target filesystem.

  • Customize the target filesystem directly and rebuild the image. The target filesystem is available under output/target/. You can simply make your changes here and run make afterwards - this will rebuild the target filesystem image. This method allows you to do anything to the target filesystem, but if you decide to completely rebuild your toolchain and tools, these changes will be lost. This solution is therefore only useful for quick tests only: changes do not survive the make clean command. Once you have validated your changes, you should make sure that they will persist after a make clean by using one of the following methods.
  • Create a filesystem overlay: a tree of files that are copied directly over the target filesystem after it has been built. Set BR2_ROOTFS_OVERLAY to the top of the tree. .git, .svn, .hg directories, .empty files and files ending with ~ are excluded. Among these first 3 methods, this one should be preferred.
  • In the Buildroot configuration, you can specify the paths to one or more post-build scripts. These scripts are called in the given order, after Buildroot builds all the selected software, but before the rootfs images are assembled. The BR2_ROOTFS_POST_BUILD_SCRIPT allows you to specify the location of your post-build scripts. This option can be found in the System configuration menu. The destination root filesystem folder is given as the first argument to these scripts, and these scripts can then be used to remove or modify any file in your target filesystem. You should, however, use this feature with care. Whenever you find that a certain package generates wrong or unneeded files, you should fix that package rather than work around it with some post-build cleanup scripts. You may also use these variables in your post-build script:

    • BR2_CONFIG: the path to the Buildroot .config file
    • HOST_DIR, STAGING_DIR, TARGET_DIR: see the section called “generic-package reference”
    • BUILD_DIR: the directory where packages are extracted and built
    • BINARIES_DIR: the place where all binary files (aka images) are stored
    • BASE_DIR: the base output directory
  • Create your own target skeleton. You can start with the default skeleton available under system/skeleton and then customize it to suit your needs. The BR2_ROOTFS_SKELETON_CUSTOM and BR2_ROOTFS_SKELETON_CUSTOM_PATH will allow you to specify the location of your custom skeleton. These options can be found in the System configuration menu. At build time, the contents of the skeleton are copied to output/target before any package installation. Note that this method is not recommended, as it duplicates the entire skeleton, which prevents from taking advantage of the fixes or improvements brought to the default Buildroot skeleton. The recommended method is to use the post-build scripts mechanism described in the previous item.

Note also that you can use the post-image scripts if you want to perform some specific actions after all filesystem images have been created (for example to automatically extract your root filesystem tarball in a location exported by your NFS server, or to create a special firmware image that bundles your root filesystem and kernel image, or any other custom action), you can specify a space-separated list of scripts in the BR2_ROOTFS_POST_IMAGE_SCRIPT configuration option. This option can be found in the System configuration menu as well.

Each of those scripts will be called with the path to the images output directory as first argument, and will be executed with the main Buildroot source directory as the current directory. Those scripts will be executed as the user that executes Buildroot, which should normally not be the root user. Therefore, any action requiring root permissions in one of these post-image scripts will require special handling (usage of fakeroot or sudo), which is left to the script developer.

Just like for the post-build scripts mentioned above, you also have access to the following environment variables from your post-image scripts: BR2_CONFIG, BUILD_DIR, HOST_DIR, STAGING_DIR, TARGET_DIR, BINARIES_DIR and BASE_DIR.

Additionally, each of the BR2_ROOTFS_POST_BUILD_SCRIPT and BR2_ROOTFS_POST_IMAGE_SCRIPT scripts will be passed the arguments specified in BR2_ROOTFS_POST_SCRIPT_ARGS (if that is not empty). All the scripts will be passed the exact same set of arguments, it is not possible to pass different sets of arguments to each script.

3.3.2. Customizing the BusyBox configuration

BusyBox is very configurable, and you may want to customize it. You can follow these simple steps to do so. This method isn’t optimal, but it’s simple, and it works:

  • Do an initial compilation of Buildroot, with busybox, without trying to customize it.
  • Invoke make busybox-menuconfig. The nice configuration tool appears, and you can customize everything.
  • Run the compilation of Buildroot again.

Otherwise, you can simply change the package/busybox/busybox-<version>.config file, if you know the options you want to change, without using the configuration tool.

If you want to use an existing config file for busybox, then see Section 3.5.5, “Environment variables”.

3.3.3. Customizing the uClibc configuration

Just like BusyBox Section 3.3.2, “Customizing the BusyBox configuration”, uClibc offers a lot of configuration options. They allow you to select various functionalities depending on your needs and limitations.

The easiest way to modify the configuration of uClibc is to follow these steps:

  • Do an initial compilation of Buildroot without trying to customize uClibc.
  • Invoke make uclibc-menuconfig. The nice configuration assistant, similar to the one used in the Linux kernel or Buildroot, appears. Make your configuration changes as appropriate.
  • Copy the $(O)/build/uClibc-VERSION/.config file to a different place (e.g. board/MANUFACTURER/BOARDNAME/uClibc.config) and adjust the uClibc configuration file option BR2_UCLIBC_CONFIG to refer to this configuration instead of the default one.
  • Run the compilation of Buildroot again.

Otherwise, you can simply change package/uclibc/uClibc-VERSION.config, without running the configuration assistant.

If you want to use an existing config file for uClibc, then see Section 3.5.5, “Environment variables”.

3.3.4. Customizing the Linux kernel configuration

The Linux kernel configuration can be customized just like BusyBox Section 3.3.2, “Customizing the BusyBox configuration” and uClibc Section 3.3.3, “Customizing the uClibc configuration” using make linux-menuconfig. Make sure you have enabled the kernel build in make menuconfig first. Once done, run make to (re)build everything.

If you want to use an existing config file for Linux, then see Section 3.5.5, “Environment variables”.

3.3.5. Customizing the toolchain

There are three distinct types of toolchain backend supported in Buildroot, available under the menu Toolchain, invoking make menuconfig.

Using the external toolchain backend

There is no way of tuning an external toolchain since Buildroot does not generate it.

It also requires to set the Buildroot settings according to the toolchain ones (see the section called “External toolchain backend”).

When using an external toolchain, Buildroot generates a wrapper program, that transparently passes the appropriate options (according to the configuration) to the external toolchain programs. In case you need to debug this wrapper to check exactly what arguments are passed, you can set the environment variable BR2_DEBUG_WRAPPER to either one of:

  • 0, empty or not set: no debug
  • 1: trace all arguments on a single line
  • 2: trace one argument per line

Using the internal Buildroot toolchain backend

The internal Buildroot toolchain backend allows to generate toolchains based on uClibc, glibc and eglibc. Generation of (e)glibc-based toolchains is still experimental in Buildroot.

It allows to tune major settings, such as:

These settings are available after selecting the Buildroot toolchain type in the menu Toolchain.

3.4. Storing the configuration

When you have a buildroot configuration that you are satisfied with and you want to share it with others, put it under revision control or move on to a different buildroot project, you need to store the configuration so it can be rebuilt later. The configuration that needs to be stored consists of the buildroot configuration, the configuration files for packages that you use (kernel, busybox, uClibc, …), and your rootfs modifications.

3.4.1. Basics for storing the configuration

Buildroot configuration

For storing the buildroot configuration itself, buildroot offers the following command: make savedefconfig.

This strips the buildroot configuration down by removing configuration options that are at their default value. The result is stored in a file called defconfig. If you want to save it in another place, change the BR2_DEFCONFIG option, or call make with make savedefconfig BR2_DEFCONFIG=<path-to-defconfig>. The usual place is configs/<boardname>_defconfig. The configuration can then be rebuilt by running make <boardname>_defconfig.

Alternatively, you can copy the file to any other place and rebuild with make defconfig BR2_DEFCONFIG=<path-to-defconfig-file>.

Other package configuration

The configuration files for busybox, the linux kernel, barebox and uClibc should be stored as well if changed. For each of these, a buildroot configuration option exists to point to an input configuration file, e.g. BR2_LINUX_KERNEL_CUSTOM_CONFIG_FILE. To save their configuration, set those configuration options to a path outside your output directory, e.g. board/<manufacturer>/<boardname>/linux.config. Then, copy the configuration files to that path.

Make sure that you create a configuration file before changing the BR2_LINUX_KERNEL_CUSTOM_CONFIG_FILE etc. options. Otherwise, buildroot will try to access this config file, which doesn’t exist yet, and will fail. You can create the configuration file by running make linux-menuconfig etc.

Buildroot provides a few helper targets to make the saving of configuration files easier.

  • make linux-update-defconfig saves the linux configuration to the path specified by BR2_LINUX_KERNEL_CUSTOM_CONFIG_FILE. It simplifies the config file by removing default values. However, this only works with kernels starting from 2.6.33. For earlier kernels, use make linux-update-config.
  • make busybox-update-config saves the busybox configuration to the path specified by BR2_PACKAGE_BUSYBOX_CONFIG.
  • make uclibc-update-config saves the uClibc configuration to the path specified by BR2_UCLIBC_CONFIG.
  • make barebox-update-defconfig saves the barebox configuration to the path specified by BR2_TARGET_BAREBOX_CUSTOM_CONFIG_FILE.
  • For at91bootstrap3, no helper exists so you have to copy the config file manually to BR2_TARGET_AT91BOOTSTRAP3_CUSTOM_CONFIG_FILE.

3.4.2. Creating your own board support

Creating your own board support in Buildroot allows users of a particular hardware platform to easily build a system that is known to work.

To do so, you need to create a normal Buildroot configuration that builds a basic system for the hardware: toolchain, kernel, bootloader, filesystem and a simple BusyBox-only userspace. No specific package should be selected: the configuration should be as minimal as possible, and should only build a working basic BusyBox system for the target platform. You can of course use more complicated configurations for your internal projects, but the Buildroot project will only integrate basic board configurations. This is because package selections are highly application-specific.

Once you have a known working configuration, run make savedefconfig. This will generate a minimal defconfig file at the root of the Buildroot source tree. Move this file into the configs/ directory, and rename it <boardname>_defconfig.

It is recommended to use as much as possible upstream versions of the Linux kernel and bootloaders, and to use as much as possible default kernel and bootloader configurations. If they are incorrect for your board, or no default exists, we encourage you to send fixes to the corresponding upstream projects.

However, in the mean time, you may want to store kernel or bootloader configuration or patches specific to your target platform. To do so, create a directory board/<manufacturer> and a subdirectory board/<manufacturer>/<boardname>. You can then store your patches and configurations in these directories, and reference them from the main Buildroot configuration.

3.4.3. Step-by-step instructions for storing configuration

To store the configuration for a specific product, device or application, it is advisable to use the same conventions as for the board support: put the buildroot defconfig in the configs directory, and any other files in a subdirectory of the boards directory. This section gives step-by-step instructions about how to do that. Of course, you can skip the steps that are not relevant for your use case.

  1. make menuconfig to configure toolchain, packages and kernel.
  2. make linux-menuconfig to update the kernel config, similar for other configuration.
  3. mkdir -p board/<manufacturer>/<boardname>
  4. Set the following options to board/<manufacturer>/<boardname>/<package>.config (as far as they are relevant):

    • BR2_LINUX_KERNEL_CUSTOM_CONFIG_FILE
    • BR2_PACKAGE_BUSYBOX_CONFIG
    • BR2_UCLIBC_CONFIG
    • BR2_TARGET_AT91BOOTSTRAP3_CUSTOM_CONFIG_FILE
    • BR2_TARGET_BAREBOX_CUSTOM_CONFIG_FILE
  5. Write the configuration files:

    • make linux-update-defconfig
    • make busybox-update-config
    • make uclibc-update-config
    • cp <output>/build/at91bootstrap3-*/.config board/<manufacturer>/<boardname>/at91bootstrap3.config
    • make barebox-update-defconfig
  6. Create board/<manufacturer>/<boardname>/fs-overlay/ and fill it with additional files you need on your rootfs, e.g. board/<manufacturer>/<boardname>/fs-overlay/etc/inittab. Set BR2_ROOTFS_OVERLAY to board/<manufacturer>/<boardname>/fs-overlay.
  7. Create a post-build script board/<manufacturer>/<boardname>/post-build.sh. Set BR2_ROOTFS_POST_BUILD_SCRIPT to board/<manufacturer>/<boardname>/post-build.sh
  8. If additional setuid permissions have to be set or device nodes have to be created, create board/<manufacturer>/<boardname>/device_table.txt and add that path to BR2_ROOTFS_DEVICE_TABLE.
  9. make savedefconfig to save the buildroot configuration.
  10. cp defconfig configs/<boardname>_defconfig
  11. To add patches to the linux build, set BR2_LINUX_KERNEL_PATCH to board/<manufacturer>/<boardname>/patches/linux/ and add your patches in that directory. Each patch should be called linux-<num>-<description>.patch. Similar for U-Boot, barebox, at91bootstrap and at91bootstrap3.
  12. If you need modifications to other packages, or if you need to add packages, do that directly in the packages/ directory, following the instructions in Section 7.2, “Adding new packages to Buildroot”.

3.4.4. Customizing packages

It is sometimes useful to apply extra patches to packages - over and above those provided in Buildroot. This might be used to support custom features in a project, for example, or when working on a new architecture.

The BR2_GLOBAL_PATCH_DIR configuration option can be used to specify a space separated list of one or more directories containing package patches. By specifying multiple global patch directories, a user could implement a layered approach to patches. This could be useful when a user has multiple boards that share a common processor architecture. It is often the case that a subset of patches for a package need to be shared between the different boards a user has. However, each board may require specific patches for the package that build on top of the common subset of patches.

For a specific version <packageversion> of a specific package <packagename>, patches are applied from BR2_GLOBAL_PATCH_DIR as follows:

  1. For every directory - <global-patch-dir> - that exists in BR2_GLOBAL_PATCH_DIR, a <package-patch-dir> will be determined as follows:

    • <global-patch-dir>/<packagename>/<packageversion>/ if the directory exists.
    • Otherwise, <global-patch-dir>/<packagename> if the directory exists.
  2. Patches will then be applied from a <package-patch-dir> as follows:

    • If a series file exists in the package directory, then patches are applied according to the series file;
    • Otherwise, patch files matching <packagename>-*.patch are applied in alphabetical order. So, to ensure they are applied in the right order, it is highly recommended to name the patch files like this: <packagename>-<number>-<description>.patch, where <number> refers to the apply order.

For information about how patches are applied for a package, see Section 7.3.2, “How patches are applied”

The BR2_GLOBAL_PATCH_DIR option is the preferred method for specifying a custom patch directory for packages. It can be used to specify a patch directory for any package in buildroot. It should also be used in place of the custom patch directory options that are available for packages such as U-Boot and Barebox. By doing this, it will allow a user to manage their patches from one top-level directory.

The exception to BR2_GLOBAL_PATCH_DIR being the preferred method for specifying custom patches is BR2_LINUX_KERNEL_PATCH. BR2_LINUX_KERNEL_PATCH should be used to specify kernel patches that are available at an URL. Note: BR2_LINUX_KERNEL_PATCH specifies kernel patches that are applied after patches available in BR2_GLOBAL_PATCH_DIR, as it is done from a post-patch hook of the Linux package.

An example directory structure for where a user has multiple directories specified for BR2_GLOBAL_PATCH_DIR may look like this:

board/
+-- common-fooarch
|   +-- patches
|       +-- linux
|       |   +-- linux-patch1.patch
|       |   +-- linux-patch2.patch
|       +-- uboot
|       +-- foopkg
+-- fooarch-board
    +-- patches
        +-- linux
        |   +-- linux-patch3.patch
        +-- uboot
        +-- foopkg

If the user has the BR2_GLOBAL_PATCH_DIR configuration option set as follows:

BR2_GLOBAL_PATCH_DIR="board/common-fooarch/patches board/fooarch-board/patches"

Then the patches would applied as follows for the Linux kernel:

  1. board/common-fooarch/patches/linux/linux-patch1.patch
  2. board/common-fooarch/patches/linux/linux-patch2.patch
  3. board/fooarch-board/patches/linux/linux-patch3.patch

3.4.5. Keeping customizations outside Buildroot

The Buildroot community recommends and encourages upstreaming to the official Buildroot version the packages and board support that are written by developers. However, it is sometimes not possible or desirable because some of these packages or board support are highly specific or proprietary.

In this case, Buildroot users are offered two choices:

  • They can add their packages, board support and configuration files directly within the Buildroot tree, and maintain them by using branches in a version control system.
  • They can use the BR2_EXTERNAL mechanism, which allows to keep package recipes, board support and configuration files outside of the Buildroot tree, while still having them nicely integrated in the build logic. The following paragraphs give details on how to use BR2_EXTERNAL.

BR2_EXTERNAL is an environment variable that can be used to point to a directory that contains Buildroot customizations. It can be passed to any Buildroot make invocation. It is automatically saved in the hidden .br-external file in the output directory. By doing this, there is no need to pass BR2_EXTERNAL at every make invocation. It can however be changed at any time by passing a new value, and can be removed by passing an empty value.

Note: the BR2_EXTERNAL path can be either an absolute or a relative path, but if it’s passed as a relative path, it is important to note that it is interpreted relative to the main Buildroot source directory, not the Buildroot output directory.

Some examples:

 buildroot/ $ make BR2_EXTERNAL=/path/to/foobar menuconfig

Starting from now on, external definitions from the /path/to/foobar directory will be used:

 buildroot/ $ make
 buildroot/ $ make legal-info

We can switch to another external definitions directory at any time:

 buildroot/ $ make BR2_EXTERNAL=/where/we/have/barfoo xconfig

Or disable the usage of external definitions:

 buildroot/ $ make BR2_EXTERNAL= xconfig

BR2_EXTERNAL then allows three different things:

  • One can store all the board-specific configuration files there, such as the kernel configuration, the root filesystem overlay, or any other configuration file for which Buildroot allows to set its location. The BR2_EXTERNAL value is available within the Buildroot configuration using $(BR2_EXTERNAL). As an example, one could set the BR2_ROOTFS_OVERLAY Buildroot option to $(BR2_EXTERNAL)/board/<boardname>/overlay/ (to specify a root filesystem overlay), or the BR2_LINUX_KERNEL_CUSTOM_CONFIG_FILE Buildroot option to $(BR2_EXTERNAL)/board/<boardname>/kernel.config (to specify the location of the kernel configuration file). To achieve this, it is recommended but not mandatory, to store those details in directories called board/<boardname>/ under BR2_EXTERNAL. This matches the directory structure used within Buildroot.
  • One can store package recipes (i.e. Config.in and <packagename>.mk), or even custom configuration options and make logic. Buildroot automatically includes BR2_EXTERNAL/Config.in to make it appear in the top-level configuration menu, and includes BR2_EXTERNAL/external.mk with the rest of the makefile logic. Providing those two files is mandatory, but they can be empty.

    The main usage of this is to store package recipes. The recommended way to do this is to write a BR2_EXTERNAL/Config.in that looks like:

    source "$BR2_EXTERNAL/package/package1/Config.in"
    source "$BR2_EXTERNAL/package/package2/Config.in"

    Then, have a BR2_EXTERNAL/external.mk file that looks like:

    include $(sort $(wildcard $(BR2_EXTERNAL)/package/*/*.mk))

    And then in BR2_EXTERNAL/package/package1 and BR2_EXTERNAL/package/package2 create normal Buildroot package recipes, as explained in Section 7.2, “Adding new packages to Buildroot”.

  • One can store Buildroot defconfigs in the configs subdirectory of BR2_EXTERNAL. Buildroot will automatically show them in the output of make help and allow them to be loaded with the normal make <name>_defconfig command. They will be visible under the User-provided configs:' label in the make help output.

In the end, a typical BR2_EXTERNAL directory organization would generally be:

$(BR2_EXTERNAL)/
+-- Config.in
+-- external.mk
+-- board/
|   +-- <boardname>/
|       +-- linux.config
|       +-- overlay/
|           +-- etc/
|               +-- <some file>
+-- configs/
|   +-- <boardname>_defconfig
+-- package/
    +-- package1/
    |    +-- Config.in
    |    +-- package1.mk
    +-- package2/
        +-- Config.in
        +-- package2.mk

3.5. Daily use

3.5.1. Understanding when a full rebuild is necessary

Buildroot does not attempt to detect what parts of the system should be rebuilt when the system configuration is changed through make menuconfig, make xconfig or one of the other configuration tools. In some cases, Buildroot should rebuild the entire system, in some cases, only a specific subset of packages. But detecting this in a completely reliable manner is very difficult, and therefore the Buildroot developers have decided to simply not attempt to do this.

Instead, it is the responsibility of the user to know when a full rebuild is necessary. As a hint, here are a few rules of thumb that can help you understand how to work with Buildroot:

  • When the target architecture configuration is changed, a complete rebuild is needed. Changing the architecture variant, the binary format or the floating point strategy for example has an impact on the entire system.
  • When the toolchain configuration is changed, a complete rebuild generally is needed. Changing the toolchain configuration often involves changing the compiler version, the type of C library or its configuration, or some other fundamental configuration item, and these changes have an impact on the entire system.
  • When an additional package is added to the configuration, a full rebuild is not necessarily needed. Buildroot will detect that this package has never been built, and will build it. However, if this package is a library that can optionally be used by packages that have already been built, Buildroot will not automatically rebuild those. Either you know which packages should be rebuilt, and you can rebuild them manually, or you should do a full rebuild. For example, let’s suppose you have built a system with the ctorrent package, but without openssl. Your system works, but you realize you would like to have SSL support in ctorrent, so you enable the openssl package in Buildroot configuration and restart the build. Buildroot will detect that openssl should be built and will be build it, but it will not detect that ctorrent should be rebuilt to benefit from openssl to add OpenSSL support. You will either have to do a full rebuild, or rebuild ctorrent itself.
  • When a package is removed from the configuration, Buildroot does not do anything special. It does not remove the files installed by this package from the target root filesystem or from the toolchain sysroot. A full rebuild is needed to get rid of this package. However, generally you don’t necessarily need this package to be removed right now: you can wait for the next lunch break to restart the build from scratch.
  • When the sub-options of a package are changed, the package is not automatically rebuilt. After making such changes, rebuilding only this package is often sufficient, unless enabling the package sub-option adds some features to the package that are useful for another package which has already been built. Again, Buildroot does not track when a package should be rebuilt: once a package has been built, it is never rebuilt unless explicitly told to do so.
  • When a change to the root filesystem skeleton is made, a full rebuild is needed. However, when changes to the root filesystem overlay, a post-build script or a post-image script are made, there is no need for a full rebuild: a simple make invocation will take the changes into account.

Generally speaking, when you’re facing a build error and you’re unsure of the potential consequences of the configuration changes you’ve made, do a full rebuild. If you get the same build error, then you are sure that the error is not related to partial rebuilds of packages, and if this error occurs with packages from the official Buildroot, do not hesitate to report the problem! As your experience with Buildroot progresses, you will progressively learn when a full rebuild is really necessary, and you will save more and more time.

For reference, a full rebuild is achieved by running:

$ make clean all

3.5.2. Understanding how to rebuild packages

One of the most common questions asked by Buildroot users is how to rebuild a given package or how to remove a package without rebuilding everything from scratch.

Removing a package is unsupported by Buildroot without rebuilding from scratch. This is because Buildroot doesn’t keep track of which package installs what files in the output/staging and output/target directories, or which package would be compiled differently depending on the availability of another package.

The easiest way to rebuild a single package from scratch is to remove its build directory in output/build. Buildroot will then re-extract, re-configure, re-compile and re-install this package from scratch. You can ask buildroot to do this with the make <package>-dirclean command.

On the other hand, if you only want to restart the build process of a package from its compilation step, you can run make <package>-rebuild, followed by make or make <package>. It will restart the compilation and installation of the package, but not from scratch: it basically re-executes make and make install inside the package, so it will only rebuild files that changed.

If you want to restart the build process of a package from its configuration step, you can run make <package>-reconfigure, followed by make or make <package>. It will restart the configuration, compilation and installation of the package.

Internally, Buildroot creates so-called stamp files to keep track of which build steps have been completed for each package. They are stored in the package build directory, output/build/<package>-<version>/ and are named .stamp_<step-name>. The commands detailed above simply manipulate these stamp files to force Buildroot to restart a specific set of steps of a package build process.

Further details about package special make targets are explained in Section 6.2.5, “Package-specific make targets”.

3.5.3. Offline builds

If you intend to do an offline build and just want to download all sources that you previously selected in the configurator (menuconfig, nconfig, xconfig or gconfig), then issue:

 $ make source

You can now disconnect or copy the content of your dl directory to the build-host.

3.5.4. Building out-of-tree

As default, everything built by Buildroot is stored in the directory output in the Buildroot tree.

Buildroot also supports building out of tree with a syntax similar to the Linux kernel. To use it, add O=<directory> to the make command line:

 $ make O=/tmp/build

Or:

 $ cd /tmp/build; make O=$PWD -C path/to/buildroot

All the output files will be located under /tmp/build. If the O path does not exist, Buildroot will create it.

Note: the O path can be either an absolute or a relative path, but if it’s passed as a relative path, it is important to note that it is interpreted relative to the main Buildroot source directory, not the current working directory.

When using out-of-tree builds, the Buildroot .config and temporary files are also stored in the output directory. This means that you can safely run multiple builds in parallel using the same source tree as long as they use unique output directories.

For ease of use, Buildroot generates a Makefile wrapper in the output directory - so after the first run, you no longer need to pass O=<…> and -C <…>, simply run (in the output directory):

 $ make <target>

3.5.5. Environment variables

Buildroot also honors some environment variables, when they are passed to make or set in the environment:

  • HOSTCXX, the host C++ compiler to use
  • HOSTCC, the host C compiler to use
  • UCLIBC_CONFIG_FILE=<path/to/.config>, path to the uClibc configuration file, used to compile uClibc, if an internal toolchain is being built. Note that the uClibc configuration file can also be set from the configuration interface, so through the Buildroot .config file; this is the recommended way of setting it.
  • BUSYBOX_CONFIG_FILE=<path/to/.config>, path to the BusyBox configuration file. Note that the BusyBox configuration file can also be set from the configuration interface, so through the Buildroot .config file; this is the recommended way of setting it.
  • BR2_DL_DIR to override the directory in which Buildroot stores/retrieves downloaded files Note that the Buildroot download directory can also be set from the configuration interface, so through the Buildroot .config file; this is the recommended way of setting it.
  • BR2_GRAPH_ALT, if set and non-empty, to use an alternate color-scheme in build-time graphs
  • BR2_GRAPH_OUT to set the filetype of generated graphs, either pdf (the default), or png.
  • BR2_GRAPH_DEPS_OPTS to pass extra options to the dependency graph; see Section 3.5.7, “Graphing the dependencies between packages” for the accepted options
  • BR2_GRAPH_DOT_OPTS is passed verbatim as options to the dot utility to draw the dependency graph.

An example that uses config files located in the toplevel directory and in your $HOME:

 $ make UCLIBC_CONFIG_FILE=uClibc.config BUSYBOX_CONFIG_FILE=$HOME/bb.config

If you want to use a compiler other than the default gcc or g++ for building helper-binaries on your host, then do

 $ make HOSTCXX=g++-4.3-HEAD HOSTCC=gcc-4.3-HEAD

3.5.6. Dealing efficiently with filesystem images

Filesystem images can get pretty big, depending on the filesystem you choose, the number of packages, whether you provisioned free space… Yet, some locations in the filesystems images may just be empty (e.g. a long run of zeroes); such a file is called a sparse file.

Most tools can handle sparse files efficiently, and will only store or write those parts of a sparse file that are not empty.

For example:

  • tar accepts the -S option to tell it to only store non-zero blocks of sparse files:

    • tar cf archive.tar -S [files…] will efficiently store sparse files in a tarball
    • tar xf archive.tar -S will efficiently store sparse files extracted from a tarball
  • cp accepts the --sparse=WHEN option (WHEN is one of auto, never or always):

    • cp --sparse=always source.file dest.file will make dest.file a sparse file if source.file has long runs of zeroes

Other tools may have similar options. Please consult their respective man pages.

You can use sparse files if you need to store the filesystem images (e.g. to transfer from one machine to another), or if you need to send them (e.g. to the Q&A team).

Note however that flashing a filesystem image to a device while using the sparse mode of dd may result in a broken filesystem (e.g. the block bitmap of an ext2 filesystem may be corrupted; or, if you have sparse files in your filesystem, those parts may not be all-zeroes when read back). You should only use sparse files when handling files on the build machine, not when transferring them to an actual device that will be used on the target.

3.5.7. Graphing the dependencies between packages

One of Buildroot’s jobs is to know the dependencies between packages, and make sure they are built in the right order. These dependencies can sometimes be quite complicated, and for a given system, it is often not easy to understand why such or such package was brought into the build by Buildroot.

In order to help understanding the dependencies, and therefore better understand what is the role of the different components in your embedded Linux system, Buildroot is capable of generating dependency graphs.

To generate a dependency graph of the full system you have compiled, simply run:

make graph-depends

You will find the generated graph in output/graphs/graph-depends.pdf.

If your system is quite large, the dependency graph may be too complex and difficult to read. It is therefore possible to generate the dependency graph just for a given package:

make <pkg>-graph-depends

You will find the generated graph in output/graph/<pkg>-graph-depends.pdf.

Note that the dependency graphs are generated using the dot tool from the Graphviz project, which you must have installed on your system to use this feature. In most distributions, it is available as the graphviz package.

By default, the dependency graphs are generated in the PDF format. However, by passing the BR2_GRAPH_OUT environment variable, you can switch to other output formats, such as PNG, PostScript or SVG. All formats supported by the -T option of the dot tool are supported.

BR2_GRAPH_OUT=svg make graph-depends

The graph-depends behaviour can be controlled by setting options in the BR2_GRAPH_DEPS_OPTS environment variable. The accepted options are:

  • --depth N, -d N, to limit the dependency depth to N levels. The default, 0, means no limit.
  • --transitive, --no-transitive, to draw (or not) the transitive dependencies. The default is to not draw transitive dependencies.
  • --colours R,T,H, the comma-separated list of colours to draw the root package (R), the target packages (T) and the host packages (H). Defaults to: lightblue,grey,gainsboro
BR2_GRAPH_DEPS_OPTS='-d 3 --no-transitive --colours=red,green,blue' make graph-depends

3.5.8. Graphing the build duration

When the build of a system takes a long time, it is sometimes useful to be able to understand which packages are the longest to build, to see if anything can be done to speed up the build. In order to help such build time analysis, Buildroot collects the build time of each step of each package, and allows to generate graphs from this data.

To generate the build time graph after a build, run:

make graph-build

This will generate a set of files in output/graphs :

  • build.hist-build.pdf, a histogram of the build time for each package, ordered in the build order.
  • build.hist-duration.pdf, a histogram of the build time for each package, ordered by duration (longest first)
  • build.hist-name.pdf, a histogram of the build time for each package, order by package name.
  • build.pie-packages.pdf, a pie chart of the build time per package
  • build.pie-steps.pdf, a pie chart of the global time spent in each step of the packages build process.

This graph-build target requires the Python Matplotlib and Numpy libraries to be installed (python-matplotlib and python-numpy on most distributions), and also the argparse module if you’re using a Python version older than 2.7 (python-argparse on most distributions).

By default, the output format for the graph is PDF, but a different format can be selected using the BR2_GRAPH_OUT environment variable. The only other format supported is PNG:

BR2_GRAPH_OUT=png make graph-build

3.6. Integration with Eclipse

While a part of the embedded Linux developers like classical text editors like Vim or Emacs, and command-line based interfaces, a number of other embedded Linux developers like richer graphical interfaces to do their development work. Eclipse being one of the most popular Integrated Development Environment, Buildroot integrates with Eclipse in order to ease the development work of Eclipse users.

Our integration with Eclipse simplifies the compilation, remote execution and remote debugging of applications and libraries that are built on top of a Buildroot system. It does not integrate the Buildroot configuration and build processes themselves with Eclipse. Therefore, the typical usage model of our Eclipse integration would be:

  • Configure your Buildroot system with make menuconfig, make xconfig or any other configuration interface provided with Buildroot.
  • Build your Buildroot system by running make.
  • Start Eclipse to develop, execute and debug your own custom applications and libraries, that will rely on the libraries built and installed by Buildroot.

The Buildroot Eclipse integration installation process and usage is described in detail at https://github.com/mbats/eclipse-buildroot-bundle/wiki.

3.7. Hacking Buildroot

If Buildroot does not yet fit all your requirements, you may be interested in hacking it to add:



[3] This terminology differs from what is used by GNU configure, where the host is the machine on which the application will run (which is usually the same as target)

Chapter 4. Frequently Asked Questions & Troubleshooting

4.1. The boot hangs after Starting network…

If the boot process seems to hang after the following messages (messages not necessarily exactly similar, depending on the list of packages selected):

Freeing init memory: 3972K
Initializing random number generator... done.
Starting network...
Starting dropbear sshd: generating rsa key... generating dsa key... OK

then it means that your system is running, but didn’t start a shell on the serial console. In order to have the system start a shell on your serial console, you have to go into the Buildroot configuration, in System configuration, modify Run a getty (login prompt) after boot and set the appropriate port and baud rate in the getty options submenu. This will automatically tune the /etc/inittab file of the generated system so that a shell starts on the correct serial port.

4.2. Why is there no compiler on the target?

It has been decided that support for the native compiler on the target would be stopped from the Buildroot-2012.11 release because:

  • this feature was neither maintained nor tested, and often broken;
  • this feature was only available for Buildroot toolchains;
  • Buildroot mostly targets small or very small target hardware with limited resource onboard (CPU, ram, mass-storage), for which compiling does not make much sense.

If you need a compiler on your target anyway, then Buildroot is not suitable for your purpose. In such case, you need a real distribution and you should opt for something like:

4.3. Why are there no development files on the target?

Since there is no compiler available on the target (see Section 4.2, “Why is there no compiler on the target?”), it does not make sense to waste space with headers or static libraries.

Therefore, those files are always removed from the target since the Buildroot-2012.11 release.

4.4. Why is there no documentation on the target?

Because Buildroot mostly targets small or very small target hardware with limited resource onboard (CPU, ram, mass-storage), it does not make sense to waste space with the documentation data.

If you need documentation data on your target anyway, then Buildroot is not suitable for your purpose, and you should look for a real distribution (see: Section 4.2, “Why is there no compiler on the target?”).

4.5. Why are some packages not visible in the Buildroot config menu?

If a package exists in the Buildroot tree and does not appear in the config menu, this most likely means that some of the package’s dependencies are not met.

To know more about the dependencies of a package, search for the package symbol in the config menu (see Section 3.2, “make tips”).

Then, you may have to recursively enable several options (which correspond to the unmet dependencies) to finally be able to select the package.

If the package is not visible due to some unmet toolchain options, then you should certainly run a full rebuild (see Section 3.2, “make tips” for more explanations).

4.6. Why not use the target directory as a chroot directory?

There are plenty of reasons to not use the target directory a chroot one, among these:

  • file ownerships, modes and permissions are not correctly set in the target directory;
  • device nodes are not created in the target directory.

For these reasons, commands run through chroot, using the target directory as the new root, will most likely fail.

If you want to run the target filesystem inside a chroot, or as an NFS root, then use the tarball image generated in images/ and extract it as root.

4.7. Why doesn’t Buildroot generate binary packages (.deb, .ipkg…)?

One feature that is often discussed on the Buildroot list is the general topic of "package management". To summarize, the idea would be to add some tracking of which Buildroot package installs what files, with the goals of:

  • being able to remove files installed by a package when this package gets unselected from the menuconfig;
  • being able to generate binary packages (ipk or other format) that can be installed on the target without re-generating a new root filesystem image.

In general, most people think it is easy to do: just track which package installed what and remove it when the package is unselected. However, it is much more complicated than that:

  • It is not only about the target/ directory, but also the sysroot in host/usr/<tuple>/sysroot and the host/ directory itself. All files installed in those directories by various packages must be tracked.
  • When a package is unselected from the configuration, it is not sufficient to remove just the files it installed. One must also remove all its reverse dependencies (i.e. packages relying on it) and rebuild all those packages. For example, package A depends optionally on the OpenSSL library. Both are selected, and Buildroot is built. Package A is built with crypto support using OpenSSL. Later on, OpenSSL gets unselected from the configuration, but package A remains (since OpenSSL is an optional dependency, this is possible.) If only OpenSSL files are removed, then the files installed by package A are broken: they use a library that is no longer present on the target. Although this is technically doable, it adds a lot of complexity to Buildroot, which goes against the simplicity we try to stick to.
  • In addition to the previous problem, there is the case where the optional dependency is not even known to Buildroot. For example, package A in version 1.0 never used OpenSSL, but in version 2.0 it automatically uses OpenSSL if available. If the Buildroot .mk file hasn’t been updated to take this into account, then package A will not be part of the reverse dependencies of OpenSSL and will not be removed and rebuilt when OpenSSL is removed. For sure, the .mk file of package A should be fixed to mention this optional dependency, but in the mean time, you can have non-reproducible behaviors.
  • The request is to also allow changes in the menuconfig to be applied on the output directory without having to rebuild everything from scratch. However, this is very difficult to achieve in a reliable way: what happens when the suboptions of a package are changed (we would have to detect this, and rebuild the package from scratch and potentially all its reverse dependencies), what happens if toolchain options are changed, etc. At the moment, what Buildroot does is clear and simple so its behaviour is very reliable and it is easy to support users. If configuration changes done in menuconfig are applied after the next make, then it has to work correctly and properly in all situations, and not have some bizarre corner cases. The risk is to get bug reports like "I have enabled package A, B and C, then ran make, then disabled package C and enabled package D and ran make, then re-enabled package C and enabled package E and then there is a build failure". Or worse "I did some configuration, then built, then did some changes, built, some more changes, built, some more changes, built, and now it fails, but I don’t remember all the changes I did and in which order". This will be impossible to support.

For all these reasons, the conclusion is that adding tracking of installed files to remove them when the package is unselected, or to generate a repository of binary packages, is something that is very hard to achieve reliably and will add a lot of complexity.

On this matter, the Buildroot developers make this position statement:

  • Buildroot strives to make it easy to generate a root filesystem (hence the name, by the way.) That is what we want to make Buildroot good at: building root filesystems.
  • Buildroot is not meant to be a distribution (or rather, a distribution generator.) It is the opinion of most Buildroot developers that this is not a goal we should pursue. We believe that there are other tools better suited to generate a distro than Buildroot is. For example, Open Embedded, or openWRT, are such tools.
  • We prefer to push Buildroot in a direction that makes it easy (or even easier) to generate complete root filesystems. This is what makes Buildroot stands out in the crowd (among other things, of course!)
  • We believe that for most embedded Linux systems, binary packages are not necessary, and potentially harmful. When binary packages are used, it means that the system can be partially upgraded, which creates an enormous number of possible combinations of package versions that should be tested before doing the upgrade on the embedded device. On the other hand, by doing complete system upgrades by upgrading the entire root filesystem image at once, the image deployed to the embedded system is guaranteed to really be the one that has been tested and validated.

Chapter 5. Known issues

  • The ltp-testsuite package does not build with the default uClibc configuration used by the Buildroot toolchain backend. The LTP testsuite uses several functions that are considered obsolete, such as sigset() and others. uClibc configuration options such as DO_XSI_MATH, UCLIBC_HAS_OBSOLETE_BSD_SIGNAL and UCLIBC_SV4_DEPRECATED are needed if one wants to build the ltp-testsuite package with uClibc. You need to either use a glibc or eglibc based toolchain, or enable the appropriate options in the uClibc configuration.
  • The xfsprogs package does not build with the default uClibc configuration used by the Buildroot toolchain backend. You need to either use a glibc or eglibc based toolchain, or enable the appropriate options in the uClibc configuration.
  • The mrouted package does not build with the default uClibc configuration used by the Buildroot toolchain backend. You need to either use a glibc or eglibc based toolchain, or enable the appropriate options in the uClibc configuration.
  • The libffi package is not supported on the SuperH 2 and ARC architectures.
  • The prboom package triggers a compiler failure with the SuperH 4 compiler from Sourcery CodeBench, version 2012.09.

Chapter 6. Going further in Buildroot’s innards

6.1. How Buildroot works

As mentioned above, Buildroot is basically a set of Makefiles that download, configure, and compile software with the correct options. It also includes patches for various software packages - mainly the ones involved in the cross-compilation toolchain (gcc, binutils and uClibc).

There is basically one Makefile per software package, and they are named with the .mk extension. Makefiles are split into many different parts.

  • The toolchain/ directory contains the Makefiles and associated files for all software related to the cross-compilation toolchain: binutils, gcc, gdb, kernel-headers and uClibc.
  • The arch/ directory contains the definitions for all the processor architectures that are supported by Buildroot.
  • The package/ directory contains the Makefiles and associated files for all user-space tools and libraries that Buildroot can compile and add to the target root filesystem. There is one sub-directory per package.
  • The linux/ directory contains the Makefiles and associated files for the Linux kernel.
  • The boot/ directory contains the Makefiles and associated files for the bootloaders supported by Buildroot.
  • The system/ directory contains support for system integration, e.g. the target filesystem skeleton and the selection of an init system.
  • The fs/ directory contains the Makefiles and associated files for software related to the generation of the target root filesystem image.

Each directory contains at least 2 files:

  • something.mk is the Makefile that downloads, configures, compiles and installs the package something.
  • Config.in is a part of the configuration tool description file. It describes the options related to the package.

The main Makefile performs the following steps (once the configuration is done):

  • Create all the output directories: staging, target, build, etc. in the output directory (output/ by default, another value can be specified using O=)
  • Generate the toolchain target. When an internal toolchain is used, this means generating the cross-compilation toolchain. When an external toolchain is used, this means checking the features of the external toolchain and importing it into the Buildroot environment.
  • Generate all the targets listed in the TARGETS variable. This variable is filled by all the individual components' Makefiles. Generating these targets will trigger the compilation of the userspace packages (libraries, programs), the kernel, the bootloader and the generation of the root filesystem images, depending on the configuration.

6.2. Advanced usage

6.2.1. Using the generated toolchain outside Buildroot

You may want to compile, for your target, your own programs or other software that are not packaged in Buildroot. In order to do this you can use the toolchain that was generated by Buildroot.

The toolchain generated by Buildroot is located by default in output/host/. The simplest way to use it is to add output/host/usr/bin/ to your PATH environment variable and then to use ARCH-linux-gcc, ARCH-linux-objdump, ARCH-linux-ld, etc.

It is possible to relocate the toolchain - but then --sysroot must be passed every time the compiler is called to tell where the libraries and header files are.

It is also possible to generate the Buildroot toolchain in a directory other than output/host by using the Build options → Host dir option. This could be useful if the toolchain must be shared with other users.

6.2.2. Using gdb in Buildroot

Buildroot allows to do cross-debugging, where the debugger runs on the build machine and communicates with gdbserver on the target to control the execution of the program.

To achieve this:

  • If you are using an internal toolchain (built by Buildroot), you must enable BR2_PACKAGE_HOST_GDB, BR2_PACKAGE_GDB and BR2_PACKAGE_GDB_SERVER. This ensures that both the cross gdb and gdbserver get built, and that gdbserver gets installed to your target.
  • If you are using an external toolchain, you should enable BR2_TOOLCHAIN_EXTERNAL_GDB_SERVER_COPY, which will copy the gdbserver included with the external toolchain to the target. If your external toolchain does not have a cross gdb or gdbserver, it is also possible to let Buildroot build them, by enabling the same options as for the internal toolchain backend.

Now, to start debugging a program called foo, you should run on the target:

gdbserver :2345 foo

This will cause gdbserver to listen on TCP port 2345 for a connection from the cross gdb.

Then, on the host, you should start the cross gdb using the following command line:

<buildroot>/output/host/usr/bin/<tuple>-gdb -x <buildroot>/output/staging/usr/share/buildroot/gdbinit foo

Of course, foo must be available in the current directory, built with debugging symbols. Typically you start this command from the directory where foo is built (and not from output/target/ as the binaries in that directory are stripped).

The <buildroot>/output/staging/usr/share/buildroot/gdbinit file will tell the cross gdb where to find the libraries of the target.

Finally, to connect to the target from the cross gdb:

(gdb) target remote <target ip address>:2345

6.2.3. Using ccache in Buildroot

ccache is a compiler cache. It stores the object files resulting from each compilation process, and is able to skip future compilation of the same source file (with same compiler and same arguments) by using the pre-existing object files. When doing almost identical builds from scratch a number of times, it can nicely speed up the build process.

ccache support is integrated in Buildroot. You just have to enable Enable compiler cache in Build options. This will automatically build ccache and use it for every host and target compilation.

The cache is located in $HOME/.buildroot-ccache. It is stored outside of Buildroot output directory so that it can be shared by separate Buildroot builds. If you want to get rid of the cache, simply remove this directory.

You can get statistics on the cache (its size, number of hits, misses, etc.) by running make ccache-stats.

The make target ccache-options and the CCACHE_OPTIONS variable provide more generic access to the ccache. For example

# set cache limit size
make CCACHE_OPTIONS="--max-size=5G" ccache-options

# zero statistics counters
make CCACHE_OPTIONS="--zero-stats" ccache-options

6.2.4. Location of downloaded packages

The various tarballs that are downloaded by Buildroot are all stored in BR2_DL_DIR, which by default is the dl directory. If you want to keep a complete version of Buildroot which is known to be working with the associated tarballs, you can make a copy of this directory. This will allow you to regenerate the toolchain and the target filesystem with exactly the same versions.

If you maintain several Buildroot trees, it might be better to have a shared download location. This can be achieved by pointing the BR2_DL_DIR environment variable to a directory. If this is set, then the value of BR2_DL_DIR in the Buildroot configuration is overridden. The following line should be added to <~/.bashrc>.

 $ export BR2_DL_DIR <shared download location>

The download location can also be set in the .config file, with the BR2_DL_DIR option. Unlike most options in the .config file, this value is overridden by the BR2_DL_DIR environment variable.

6.2.5. Package-specific make targets

Running make <package> builds and installs that particular package and its dependencies.

For packages relying on the Buildroot infrastructure, there are numerous special make targets that can be called independently like this:

make <package>-<target>

The package build targets are (in the order they are executed):

command/target Description

source

Fetch the source (download the tarball, clone the source repository, etc)

depends

Build and install all dependencies required to build the package

extract

Put the source in the package build directory (extract the tarball, copy the source, etc)

patch

Apply the patches, if any

configure

Run the configure commands, if any

build

Run the compilation commands

install-staging

target package: Run the installation of the package in the staging directory, if necessary

install-target

target package: Run the installation of the package in the target directory, if necessary

install

target package: Run the 2 previous installation commands

host package: Run the installation of the package in the host directory

Additionally, there are some other useful make targets:

command/target Description

show-depends

Displays the dependencies required to build the package

graph-depends

Generate a dependency graph of the package, in the context of the current Buildroot configuration. See this section Section 3.5.7, “Graphing the dependencies between packages” for more details about dependency graphs.

dirclean

Remove the whole package build directory

rebuild

Re-run the compilation commands - this only makes sense when using the OVERRIDE_SRCDIR feature or when you modified a file directly in the build directory

reconfigure

Re-run the configure commands, then rebuild - this only makes sense when using the OVERRIDE_SRCDIR feature or when you modified a file directly in the build directory

6.2.6. Using Buildroot during development

The normal operation of Buildroot is to download a tarball, extract it, configure, compile and install the software component found inside this tarball. The source code is extracted in output/build/<package>-<version>, which is a temporary directory: whenever make clean is used, this directory is entirely removed, and re-recreated at the next make invocation. Even when a Git or Subversion repository is used as the input for the package source code, Buildroot creates a tarball out of it, and then behaves as it normally does with tarballs.

This behavior is well-suited when Buildroot is used mainly as an integration tool, to build and integrate all the components of an embedded Linux system. However, if one uses Buildroot during the development of certain components of the system, this behavior is not very convenient: one would instead like to make a small change to the source code of one package, and be able to quickly rebuild the system with Buildroot.

Making changes directly in output/build/<package>-<version> is not an appropriate solution, because this directory is removed on make clean.

Therefore, Buildroot provides a specific mechanism for this use case: the <pkg>_OVERRIDE_SRCDIR mechanism. Buildroot reads an override file, which allows the user to tell Buildroot the location of the source for certain packages. By default this override file is named local.mk and located in the top directory of the Buildroot source tree, but a different location can be specified through the BR2_PACKAGE_OVERRIDE_FILE configuration option.

In this override file, Buildroot expects to find lines of the form:

<pkg1>_OVERRIDE_SRCDIR = /path/to/pkg1/sources
<pkg2>_OVERRIDE_SRCDIR = /path/to/pkg2/sources

For example:

LINUX_OVERRIDE_SRCDIR = /home/bob/linux/
BUSYBOX_OVERRIDE_SRCDIR = /home/bob/busybox/

When Buildroot finds that for a given package, an <pkg>_OVERRIDE_SRCDIR has been defined, it will no longer attempt to download, extract and patch the package. Instead, it will directly use the source code available in in the specified directory and make clean will not touch this directory. This allows to point Buildroot to your own directories, that can be managed by Git, Subversion, or any other version control system. To achieve this, Buildroot will use rsync to copy the source code of the component from the specified <pkg>_OVERRIDE_SRCDIR to output/build/<package>-custom/.

This mechanism is best used in conjunction with the make <pkg>-rebuild and make <pkg>-reconfigure targets. A make <pkg>-rebuild all sequence will rsync the source code from <pkg>_OVERRIDE_SRCDIR to output/build/<package>-custom (thanks to rsync, only the modified files are copied), and restart the build process of just this package.

In the example of the linux package above, the developer can then make a source code change in /home/bob/linux and then run:

make linux-rebuild all

and in a matter of seconds gets the updated Linux kernel image in output/images. Similarly, a change can be made to the BusyBox source code in /home/bob/busybox, and after:

make busybox-rebuild all

the root filesystem image in output/images contains the updated BusyBox.

Chapter 7. Developer Guidelines

7.1. Coding style

Overall, these coding style rules are here to help you to add new files in Buildroot or refactor existing ones.

If you slightly modify some existing file, the important thing is to keep the consistency of the whole file, so you can:

  • either follow the potentially deprecated coding style used in this file,
  • or entirely rework it in order to make it comply with these rules.

7.1.1. Config.in file

Config.in files contain entries for almost anything configurable in Buildroot.

An entry has the following pattern:

config BR2_PACKAGE_LIBFOO
        bool "libfoo"
        depends on BR2_PACKAGE_LIBBAZ
        select BR2_PACKAGE_LIBBAR
        help
          This is a comment that explains what libfoo is.

          http://foosoftware.org/libfoo/
  • The bool, depends on, select and help lines are indented with one tab.
  • The help text itself should be indented with one tab and two spaces.

The Config.in files are the input for the configuration tool used in Buildroot, which is the regular Kconfig. For further details about the Kconfig language, refer to http://kernel.org/doc/Documentation/kbuild/kconfig-language.txt.

7.1.2. The .mk file

  • Header: The file starts with a header. It contains the module name, preferably in lowercase, enclosed between separators made of 80 hashes. A blank line is mandatory after the header:

    ################################################################################
    #
    # libfoo
    #
    ################################################################################
  • Assignment: use = preceded and followed by one space:

    LIBFOO_VERSION = 1.0
    LIBFOO_CONF_OPT += --without-python-support

    Do not align the = signs.

  • Indentation: use tab only:

    define LIBFOO_REMOVE_DOC
            $(RM) -fr $(TARGET_DIR)/usr/share/libfoo/doc \
                    $(TARGET_DIR)/usr/share/man/man3/libfoo*
    endef

    Note that commands inside a define block should always start with a tab, so make recognizes them as commands.

  • Optional dependency:

    • Prefer multi-line syntax.

      YES:

      ifeq ($(BR2_PACKAGE_PYTHON),y)
      LIBFOO_CONF_OPT += --with-python-support
      LIBFOO_DEPENDENCIES += python
      else
      LIBFOO_CONF_OPT += --without-python-support
      endif

      NO:

      LIBFOO_CONF_OPT += --with$(if $(BR2_PACKAGE_PYTHON),,out)-python-support
      LIBFOO_DEPENDENCIES += $(if $(BR2_PACKAGE_PYTHON),python,)
    • Keep configure options and dependencies close together.
  • Optional hooks: keep hook definition and assignment together in one if block.

    YES:

    ifneq ($(BR2_LIBFOO_INSTALL_DATA),y)
    define LIBFOO_REMOVE_DATA
            $(RM) -fr $(TARGET_DIR)/usr/share/libfoo/data
    endef
    LIBFOO_POST_INSTALL_TARGET_HOOKS += LIBFOO_REMOVE_DATA
    endif

    NO:

    define LIBFOO_REMOVE_DATA
            $(RM) -fr $(TARGET_DIR)/usr/share/libfoo/data
    endef
    
    ifneq ($(BR2_LIBFOO_INSTALL_DATA),y)
    LIBFOO_POST_INSTALL_TARGET_HOOKS += LIBFOO_REMOVE_DATA
    endif

7.1.3. The documentation

The documentation uses the asciidoc format.

For further details about the asciidoc syntax, refer to http://www.methods.co.nz/asciidoc/userguide.html.

7.2. Adding new packages to Buildroot

This section covers how new packages (userspace libraries or applications) can be integrated into Buildroot. It also shows how existing packages are integrated, which is needed for fixing issues or tuning their configuration.

7.2.1. Package directory

First of all, create a directory under the package directory for your software, for example libfoo.

Some packages have been grouped by topic in a sub-directory: x11r7, efl and matchbox. If your package fits in one of these categories, then create your package directory in these. New subdirectories are discouraged, however.

7.2.2. Config.in file

Then, create a file named Config.in. This file will contain the option descriptions related to our libfoo software that will be used and displayed in the configuration tool. It should basically contain:

config BR2_PACKAGE_LIBFOO
        bool "libfoo"
        help
          This is a comment that explains what libfoo is.

          http://foosoftware.org/libfoo/

The bool line, help line and other metadata information about the configuration option must be indented with one tab. The help text itself should be indented with one tab and two spaces, and it must mention the upstream URL of the project.

You can add other sub-options into a if BR2_PACKAGE_LIBFOO…endif statement to configure particular things in your software. You can look at examples in other packages. The syntax of the Config.in file is the same as the one for the kernel Kconfig file. The documentation for this syntax is available at http://kernel.org/doc/Documentation/kbuild/kconfig-language.txt

Finally you have to add your new libfoo/Config.in to package/Config.in (or in a category subdirectory if you decided to put your package in one of the existing categories). The files included there are sorted alphabetically per category and are NOT supposed to contain anything but the bare name of the package.

source "package/libfoo/Config.in"

Choosing depends on or select

The Config.in file of your package must also ensure that dependencies are enabled. Typically, Buildroot uses the following rules:

  • Use a select type of dependency for dependencies on libraries. These dependencies are generally not obvious and it therefore make sense to have the kconfig system ensure that the dependencies are selected. For example, the libgtk2 package uses select BR2_PACKAGE_LIBGLIB2 to make sure this library is also enabled. The select keyword expresses the dependency with a backward semantic.
  • Use a depends on type of dependency when the user really needs to be aware of the dependency. Typically, Buildroot uses this type of dependency for dependencies on target architecture, MMU support and toolchain options (see the section called “Dependencies on target and toolchain options”), or for dependencies on "big" things, such as the X.org system. The depends on keyword expresses the dependency with a forward semantic.

Note. The current problem with the kconfig language is that these two dependency semantics are not internally linked. Therefore, it may be possible to select a package, whom one of its dependencies/requirement is not met.

An example illustrates both the usage of select and depends on.

config BR2_PACKAGE_ACL
        bool "acl"
        select BR2_PACKAGE_ATTR
        depends on BR2_LARGEFILE
        help
          POSIX Access Control Lists, which are used to define more
          fine-grained discretionary access rights for files and
          directories.
          This package also provides libacl.

          http://savannah.nongnu.org/projects/acl

comment "acl needs a toolchain w/ largefile"
        depends on !BR2_LARGEFILE

Note that these two dependency types are only transitive with the dependencies of the same kind.

This means, in the following example:

config BR2_PACKAGE_A
        bool "Package A"

config BR2_PACKAGE_B
        bool "Package B"
        depends on BR2_PACKAGE_A

config BR2_PACKAGE_C
        bool "Package C"
        depends on BR2_PACKAGE_B

config BR2_PACKAGE_D
        bool "Package D"
        select BR2_PACKAGE_B

config BR2_PACKAGE_E
        bool "Package E"
        select BR2_PACKAGE_D
  • Selecting Package C will be visible if Package B has been selected, which in turn is only visible if Package A has been selected.
  • Selecting Package E will select Package D, which will select Package B, it will not check for the dependencies of Package B, so it will not select Package A.
  • Since Package B is selected but Package A is not, this violates the dependency of Package B on Package A. Therefore, in such a situation, the transitive dependency has to be added explicitly:
config BR2_PACKAGE_D
        bool "Package D"
        select BR2_PACKAGE_B
        depends on BR2_PACKAGE_A

config BR2_PACKAGE_E
        bool "Package E"
        select BR2_PACKAGE_D
        depends on BR2_PACKAGE_A

Overall, for package library dependencies, select should be preferred.

Note that such dependencies will ensure that the dependency option is also enabled, but not necessarily built before your package. To do so, the dependency also needs to be expressed in the .mk file of the package.

Further formatting details: see the coding style Section 7.1.1, “Config.in file”.

Dependencies on target and toolchain options

Many packages depend on certain options of the toolchain: the choice of C library, C++ support, largefile support, thread support, RPC support, IPv6 support, wchar support, or dynamic library support. Some packages can only be built on certain target architectures, or if an MMU is available in the processor.

These dependencies have to be expressed with the appropriate depends on statements in the Config.in file. Additionally, for dependencies on toolchain options, a comment should be displayed when the option is not enabled, so that the user knows why the package is not available. Dependencies on target architecture or MMU support should not be made visible in a comment: since it is unlikely that the user can freely choose another target, it makes little sense to show these dependencies explicitly.

The comment should only be visible if the config option itself would be visible when the toolchain option dependencies are met. This means that all other dependencies of the package (including dependencies on target architecture and MMU support) have to be repeated on the comment definition. To keep it clear, the depends on statement for these non-toolchain option should be kept separate from the depends on statement for the toolchain options. If there is a dependency on a config option in that same file (typically the main package) it is preferable to have a global if … endif construct rather than repeating the depends on statement on the comment and other config options.

The general format of a dependency comment for package foo is:

foo needs a toolchain w/ featA, featB, featC

for example:

aircrack-ng needs a toolchain w/ largefile, threads

or

crda needs a toolchain w/ threads

Note that this text is kept brief on purpose, so that it will fit on a 80-character terminal.

The rest of this section enumerates the different target and toolchain options, the corresponding config symbols to depend on, and the text to use in the comment.

  • Target architecture

    • Dependency symbol: BR2_powerpc, BR2_mips, … (see arch/Config.in)
    • Comment string: no comment to be added
  • MMU support

    • Dependency symbol: BR2_USE_MMU
    • Comment string: no comment to be added
  • Kernel headers

    • Dependency symbol: BR2_TOOLCHAIN_HEADERS_AT_LEAST_X_Y, (replace X_Y with the proper version, see toolchain/toolchain-common.in)
    • Comment string: headers >= X.Y (replace X.Y with the proper version)
  • C library

    • Dependency symbol: BR2_TOOLCHAIN_USES_GLIBC, BR2_TOOLCHAIN_USES_UCLIBC
    • Comment string: for the C library, a slightly different comment text is used: foo needs an (e)glibc toolchain, or foo needs an (e)glibc toolchain w/ C++
  • C++ support

    • Dependency symbol: BR2_INSTALL_LIBSTDCPP
    • Comment string: C++
  • largefile support

    • Dependency symbol: BR2_LARGEFILE
    • Comment string: largefile
  • thread support

    • Dependency symbol: BR2_TOOLCHAIN_HAS_THREADS
    • Comment string: threads (unless BR2_TOOLCHAIN_HAS_THREADS_NPTL is also needed, in which case, specifying only NPTL is sufficient)
  • NPTL thread support

    • Dependency symbol: BR2_TOOLCHAIN_HAS_THREADS_NPTL
    • Comment string: NPTL
  • RPC support

    • Dependency symbol: BR2_TOOLCHAIN_HAS_NATIVE_RPC
    • Comment string: RPC
  • IPv6 support

    • Dependency symbol: BR2_INET_IPV6
    • Comment string: IPv6 (lowercase v)
  • wchar support

    • Dependency symbol: BR2_USE_WCHAR
    • Comment string: wchar
  • dynamic library

    • Dependency symbol: !BR2_PREFER_STATIC_LIB
    • Comment string: dynamic library

Dependencies on a Linux kernel built by buildroot

Some packages need a Linux kernel to be built by buildroot. These are typically kernel modules or firmware. A comment should be added in the Config.in file to express this dependency, similar to dependencies on toolchain options. The general format is:

foo needs a Linux kernel to be built

If there is a dependency on both toolchain options and the Linux kernel, use this format:

foo needs a toolchain w/ featA, featB, featC and a Linux kernel to be built

Dependencies on udev /dev management

If a package needs udev /dev management, it should depend on symbol BR2_PACKAGE_HAS_UDEV, and the following comment should be added:

foo needs udev /dev management

If there is a dependency on both toolchain options and udev /dev management, use this format:

foo needs udev /dev management and a toolchain w/ featA, featB, featC

Dependencies on features provided by virtual packages

Some features can be provided by more than one package, such as the openGL libraries.

See Section 7.2.11, “Infrastructure for virtual packages” for more on the virtual packages.

See Section 12.4, “List of virtual packages” for the symbols to depend on if your package depends on a feature provided by a virtual package.

7.2.3. The .mk file

Finally, here’s the hardest part. Create a file named libfoo.mk. It describes how the package should be downloaded, configured, built, installed, etc.

Depending on the package type, the .mk file must be written in a different way, using different infrastructures:

Further formatting details: see the writing rules Section 7.1.2, “The .mk file”.

7.2.4. The .hash file

Optionally, you can add a third file, named libfoo.hash, that contains the hashes of the downloaded files for the libfoo package.

The hashes stored in that file are used to validate the integrity of the downloaded files.

The format of this file is one line for each file for which to check the hash, each line being space-separated, with these three fields:

  • the type of hash, one of:

    • sha1, sha224, sha256, sha384, sha512
  • the hash of the file:

    • for sha1, 40 hexadecimal characters
    • for sha224, 56 hexadecimal characters
    • for sha256, 64 hexadecimal characters
    • for sha384, 96 hexadecimal characters
    • for sha512, 128 hexadecimal characters
  • the name of the file, without any directory component

Lines starting with a # sign are considered comments, and ignored. Empty lines are ignored.

There can be more than one hash for a single file, each on its own line. In this case, all hashes must match.

Ideally, the hashes stored in this file should match the hashes published by upstream, e.g. on their website, in the e-mail announcement… If upstream provides more than one type of hash (say, sha1 and sha512), then it is best to add all those hashes in the .hash file. If upstream does not provide any hash, then compute at least one yourself, and mention this in a comment line above the hashes.

Note: the number of spaces does not matter, so one can use spaces to properly align the different fields.

The example below defines a sha1 and a sha256 published by upstream for the main libfoo-1.2.3.tar.bz2 tarball, plus two locally-computed hashes, a sha256 for a downloaded patch, and a sha1 for a downloaded binary blob:

# Hashes from: http://www.foosoftware.org/download/libfoo-1.2.3.tar.bz2.{sha1,sha256}:
sha1   486fb55c3efa71148fe07895fd713ea3a5ae343a                         libfoo-1.2.3.tar.bz2
sha256 efc8103cc3bcb06bda6a781532d12701eb081ad83e8f90004b39ab81b65d4369 libfoo-1.2.3.tar.bz2

# No upstream hashes for the following:
sha256 ff52101fb90bbfc3fe9475e425688c660f46216d7e751c4bbdb1dc85cdccacb9 libfoo-fix-blabla.patch
sha1   2d608f3c318c6b7557d551a5a09314f03452f1a1                         libfoo-data.bin

If the .hash file is present, and it contains one or more hashes for a downloaded file, the hash(es) computed by Buildroot (after download) must match the hash(es) stored in the .hash file. If one or more hashes do not match, Buildroot considers this an error, deletes the downloaded file, and aborts.

If the .hash file is present, but it does not contain a hash for a downloaded file, no check is done for that file. If you set the environment variable BR2_ENFORCE_CHECK_HASH to a non-empty value, and there is no hash for a downloaded file, Buildroot considers this an error, deletes the downloaded file, and aborts.

If the .hash file is missing, then no check is done at all.

7.2.5. Infrastructure for packages with specific build systems

By packages with specific build systems we mean all the packages whose build system is not one of the standard ones, such as autotools or CMake. This typically includes packages whose build system is based on hand-written Makefiles or shell scripts.

generic-package tutorial

01: ################################################################################
02: #
03: # libfoo
04: #
05: ################################################################################
06:
07: LIBFOO_VERSION = 1.0
08: LIBFOO_SOURCE = libfoo-$(LIBFOO_VERSION).tar.gz
09: LIBFOO_SITE = http://www.foosoftware.org/download
10: LIBFOO_LICENSE = GPLv3+
11: LIBFOO_LICENSE_FILES = COPYING
12: LIBFOO_INSTALL_STAGING = YES
13: LIBFOO_CONFIG_SCRIPTS = libfoo-config
14: LIBFOO_DEPENDENCIES = host-libaaa libbbb
15:
16: define LIBFOO_BUILD_CMDS
17:     $(MAKE) CC="$(TARGET_CC)" LD="$(TARGET_LD)" -C $(@D) all
18: endef
19:
20: define LIBFOO_INSTALL_STAGING_CMDS
21:     $(INSTALL) -D -m 0755 $(@D)/libfoo.a $(STAGING_DIR)/usr/lib/libfoo.a
22:     $(INSTALL) -D -m 0644 $(@D)/foo.h $(STAGING_DIR)/usr/include/foo.h
23:     $(INSTALL) -D -m 0755 $(@D)/libfoo.so* $(STAGING_DIR)/usr/lib
24: endef
25:
26: define LIBFOO_INSTALL_TARGET_CMDS
27:     $(INSTALL) -D -m 0755 $(@D)/libfoo.so* $(TARGET_DIR)/usr/lib
28:     $(INSTALL) -d -m 0755 $(TARGET_DIR)/etc/foo.d
29: endef
30:
31: define LIBFOO_DEVICES
32:     /dev/foo  c  666  0  0  42  0  -  -  -
33: endef
34:
35: define LIBFOO_PERMISSIONS
36:     /bin/foo  f  4755  0  0  -  -  -  -  -
37: endef
38:
39: define LIBFOO_USERS
40:     foo -1 libfoo -1 * - - - LibFoo daemon
41: endef
42:
43: $(eval $(generic-package))

The Makefile begins on line 7 to 11 with metadata information: the version of the package (LIBFOO_VERSION), the name of the tarball containing the package (LIBFOO_SOURCE) (xz-ed tarball recommended) the Internet location at which the tarball can be downloaded from (LIBFOO_SITE), the license (LIBFOO_LICENSE) and file with the license text (LIBFOO_LICENSE_FILES). All variables must start with the same prefix, LIBFOO_ in this case. This prefix is always the uppercased version of the package name (see below to understand where the package name is defined).

On line 12, we specify that this package wants to install something to the staging space. This is often needed for libraries, since they must install header files and other development files in the staging space. This will ensure that the commands listed in the LIBFOO_INSTALL_STAGING_CMDS variable will be executed.

On line 13, we specify that there is some fixing to be done to some of the libfoo-config files that were installed during LIBFOO_INSTALL_STAGING_CMDS phase. These *-config files are executable shell script files that are located in $(STAGING_DIR)/usr/bin directory and are executed by other 3rd party packages to find out the location and the linking flags of this particular package.

The problem is that all these *-config files by default give wrong, host system linking flags that are unsuitable for cross-compiling.

For example: -I/usr/include instead of -I$(STAGING_DIR)/usr/include or: -L/usr/lib instead of -L$(STAGING_DIR)/usr/lib

So some sed magic is done to these scripts to make them give correct flags. The argument to be given to LIBFOO_CONFIG_SCRIPTS is the file name(s) of the shell script(s) needing fixing. All these names are relative to $(STAGING_DIR)/usr/bin and if needed multiple names can be given.

In addition, the scripts listed in LIBFOO_CONFIG_SCRIPTS are removed from $(TARGET_DIR)/usr/bin, since they are not needed on the target.

Example 7.1. Config script: divine package

Package divine installs shell script $(STAGING_DIR)/usr/bin/divine-config.

So its fixup would be:

DIVINE_CONFIG_SCRIPTS = divine-config

Example 7.2. Config script: imagemagick package:

Package imagemagick installs the following scripts: $(STAGING_DIR)/usr/bin/{Magick,Magick++,MagickCore,MagickWand,Wand}-config

So it’s fixup would be:

IMAGEMAGICK_CONFIG_SCRIPTS = \
   Magick-config Magick++-config \
   MagickCore-config MagickWand-config Wand-config

On line 14, we specify the list of dependencies this package relies on. These dependencies are listed in terms of lower-case package names, which can be packages for the target (without the host- prefix) or packages for the host (with the host-) prefix). Buildroot will ensure that all these packages are built and installed before the current package starts its configuration.

The rest of the Makefile, lines 16..29, defines what should be done at the different steps of the package configuration, compilation and installation. LIBFOO_BUILD_CMDS tells what steps should be performed to build the package. LIBFOO_INSTALL_STAGING_CMDS tells what steps should be performed to install the package in the staging space. LIBFOO_INSTALL_TARGET_CMDS tells what steps should be performed to install the package in the target space.

All these steps rely on the $(@D) variable, which contains the directory where the source code of the package has been extracted.

On line 31..33, we define a device-node file used by this package (LIBFOO_DEVICES).

On line 35..37, we define the permissions to set to specific files installed by this package (LIBFOO_PERMISSIONS).

On lines 39..41, we define a user that is used by this package (e.g. to run a daemon as non-root) (LIBFOO_USERS).

Finally, on line 43, we call the generic-package function, which generates, according to the variables defined previously, all the Makefile code necessary to make your package working.

generic-package reference

There are two variants of the generic target. The generic-package macro is used for packages to be cross-compiled for the target. The host-generic-package macro is used for host packages, natively compiled for the host. It is possible to call both of them in a single .mk file: once to create the rules to generate a target package and once to create the rules to generate a host package:

$(eval $(generic-package))
$(eval $(host-generic-package))

This might be useful if the compilation of the target package requires some tools to be installed on the host. If the package name is libfoo, then the name of the package for the target is also libfoo, while the name of the package for the host is host-libfoo. These names should be used in the DEPENDENCIES variables of other packages, if they depend on libfoo or host-libfoo.

The call to the generic-package and/or host-generic-package macro must be at the end of the .mk file, after all variable definitions.

For the target package, the generic-package uses the variables defined by the .mk file and prefixed by the uppercased package name: LIBFOO_*. host-generic-package uses the HOST_LIBFOO_* variables. For some variables, if the HOST_LIBFOO_ prefixed variable doesn’t exist, the package infrastructure uses the corresponding variable prefixed by LIBFOO_. This is done for variables that are likely to have the same value for both the target and host packages. See below for details.

The list of variables that can be set in a .mk file to give metadata information is (assuming the package name is libfoo) :

  • LIBFOO_VERSION, mandatory, must contain the version of the package. Note that if HOST_LIBFOO_VERSION doesn’t exist, it is assumed to be the same as LIBFOO_VERSION. It can also be a revision number, branch or tag for packages that are fetched directly from their revision control system. Examples: LIBFOO_VERSION = 0.1.2 LIBFOO_VERSION = cb9d6aa9429e838f0e54faa3d455bcbab5eef057 LIBFOO_VERSION = stable
  • LIBFOO_SOURCE may contain the name of the tarball of the package. If HOST_LIBFOO_SOURCE is not specified, it defaults to LIBFOO_SOURCE. If none are specified, then the value is assumed to be libfoo-$(LIBFOO_VERSION).tar.gz. Example: LIBFOO_SOURCE = foobar-$(LIBFOO_VERSION).tar.bz2
  • LIBFOO_PATCH may contain a space-separated list of patch file names, that will be downloaded from the same location as the tarball indicated in LIBFOO_SOURCE, and then applied to the package source code. If HOST_LIBFOO_PATCH is not specified, it defaults to LIBFOO_PATCH. Note that patches that are included in Buildroot itself use a different mechanism: all files of the form <packagename>-*.patch present in the package directory inside Buildroot will be applied to the package after extraction (see patching a package Section 7.3, “Patching a package”). Finally, patches listed in the LIBFOO_PATCH variable are applied before the patches stored in the Buildroot package directory.
  • LIBFOO_SITE provides the location of the package, which can be a URL or a local filesystem path. HTTP, FTP and SCP are supported URL types for retrieving package tarballs. Git, Subversion, Mercurial, and Bazaar are supported URL types for retrieving packages directly from source code management systems. There is a helper function to make it easier to download source tarballs from GitHub (refer to the section called “How to add a package from GitHub” for details). A filesystem path may be used to specify either a tarball or a directory containing the package source code. See LIBFOO_SITE_METHOD below for more details on how retrieval works. Note that SCP URLs should be of the form scp://[user@]host:filepath, and that filepath is relative to the user’s home directory, so you may want to prepend the path with a slash for absolute paths: scp://[user@]host:/absolutepath. If HOST_LIBFOO_SITE is not specified, it defaults to LIBFOO_SITE. Examples: LIBFOO_SITE=http://www.libfoosoftware.org/libfoo LIBFOO_SITE=http://svn.xiph.org/trunk/Tremor/ LIBFOO_SITE=/opt/software/libfoo.tar.gz LIBFOO_SITE=$(TOPDIR)/../src/libfoo/
  • LIBFOO_EXTRA_DOWNLOADS lists a number of additional files that Buildroot should download from LIBFOO_SITE in addition to the main LIBFOO_SOURCE (which usually is a tarball). Buildroot will not do anything with those additional files, except download files: it will be up to the package recipe to use them from $(BR2_DL_DIR).
  • LIBFOO_SITE_METHOD determines the method used to fetch or copy the package source code. In many cases, Buildroot guesses the method from the contents of LIBFOO_SITE and setting LIBFOO_SITE_METHOD is unnecessary. When HOST_LIBFOO_SITE_METHOD is not specified, it defaults to the value of LIBFOO_SITE_METHOD. The possible values of LIBFOO_SITE_METHOD are:

    • wget for normal FTP/HTTP downloads of tarballs. Used by default when LIBFOO_SITE begins with http://, https:// or ftp://.
    • scp for downloads of tarballs over SSH with scp. Used by default when LIBFOO_SITE begins with scp://.
    • svn for retrieving source code from a Subversion repository. Used by default when LIBFOO_SITE begins with svn://. When a http:// Subversion repository URL is specified in LIBFOO_SITE, one must specify LIBFOO_SITE_METHOD=svn. Buildroot performs a checkout which is preserved as a tarball in the download cache; subsequent builds use the tarball instead of performing another checkout.
    • cvs for retrieving source code from a CVS repository. Used by default when LIBFOO_SITE begins with cvs://. The downloaded source code is cached as with the svn method. Only anonymous pserver mode is supported. LIBFOO_SITE must contain the source URL as well as the remote repository directory. The module is the package name. LIBFOO_VERSION is mandatory and must be a timestamp.
    • git for retrieving source code from a Git repository. Used by default when LIBFOO_SITE begins with git://. The downloaded source code is cached as with the svn method.
    • hg for retrieving source code from a Mercurial repository. One must specify LIBFOO_SITE_METHOD=hg when LIBFOO_SITE contains a Mercurial repository URL. The downloaded source code is cached as with the svn method.
    • bzr for retrieving source code from a Bazaar repository. Used by default when LIBFOO_SITE begins with bzr://. The downloaded source code is cached as with the svn method.
    • file for a local tarball. One should use this when LIBFOO_SITE specifies a package tarball as a local filename. Useful for software that isn’t available publicly or in version control.
    • local for a local source code directory. One should use this when LIBFOO_SITE specifies a local directory path containing the package source code. Buildroot copies the contents of the source directory into the package’s build directory.
  • LIBFOO_DEPENDENCIES lists the dependencies (in terms of package name) that are required for the current target package to compile. These dependencies are guaranteed to be compiled and installed before the configuration of the current package starts. In a similar way, HOST_LIBFOO_DEPENDENCIES lists the dependencies for the current host package.
  • LIBFOO_PROVIDES lists all the virtual packages libfoo is an implementation of. See Section 7.2.11, “Infrastructure for virtual packages”.
  • LIBFOO_INSTALL_STAGING can be set to YES or NO (default). If set to YES, then the commands in the LIBFOO_INSTALL_STAGING_CMDS variables are executed to install the package into the staging directory.
  • LIBFOO_INSTALL_TARGET can be set to YES (default) or NO. If set to YES, then the commands in the LIBFOO_INSTALL_TARGET_CMDS variables are executed to install the package into the target directory.
  • LIBFOO_CONFIG_SCRIPTS lists the names of the files in $(STAGING_DIR)/usr/bin that need some special fixing to make them cross-compiling friendly. Multiple file names separated by space can be given and all are relative to $(STAGING_DIR)/usr/bin. The files listed in LIBFOO_CONFIG_SCRIPTS are also removed from $(TARGET_DIR)/usr/bin since they are not needed on the target.
  • LIBFOO_DEVICES lists the device files to be created by Buildroot when using the static device table. The syntax to use is the makedevs one. You can find some documentation for this syntax in the Section 12.1, “Makedev syntax documentation”. This variable is optional.
  • LIBFOO_PERMISSIONS lists the changes of permissions to be done at the end of the build process. The syntax is once again the makedevs one. You can find some documentation for this syntax in the Section 12.1, “Makedev syntax documentation”. This variable is optional.
  • LIBFOO_USERS lists the users to create for this package, if it installs a program you want to run as a specific user (e.g. as a daemon, or as a cron-job). The syntax is similar in spirit to the makedevs one, and is described in the Section 12.2, “Makeuser syntax documentation”. This variable is optional.
  • LIBFOO_LICENSE defines the license (or licenses) under which the package is released. This name will appear in the manifest file produced by make legal-info. If the license appears in the following list Section 8.2, “License abbreviations”, use the same string to make the manifest file uniform. Otherwise, describe the license in a precise and concise way, avoiding ambiguous names such as BSD which actually name a family of licenses. This variable is optional. If it is not defined, unknown will appear in the license field of the manifest file for this package.
  • LIBFOO_LICENSE_FILES is a space-separated list of files in the package tarball that contain the license(s) under which the package is released. make legal-info copies all of these files in the legal-info directory. See Chapter 8, Legal notice and licensing for more information. This variable is optional. If it is not defined, a warning will be produced to let you know, and not saved will appear in the license files field of the manifest file for this package.
  • LIBFOO_REDISTRIBUTE can be set to YES (default) or NO to indicate if the package source code is allowed to be redistributed. Set it to NO for non-opensource packages: Buildroot will not save the source code for this package when collecting the legal-info.
  • LIBFOO_FLAT_STACKSIZE defines the stack size of an application built into the FLAT binary format. The application stack size on the NOMMU architecture processors can’t be enlarged at run time. The default stack size for the FLAT binary format is only 4k bytes. If the application consumes more stack, append the required number here.

The recommended way to define these variables is to use the following syntax:

LIBFOO_VERSION = 2.32

Now, the variables that define what should be performed at the different steps of the build process.

  • LIBFOO_EXTRACT_CMDS lists the actions to be performed to extract the package. This is generally not needed as tarballs are automatically handled by Buildroot. However, if the package uses a non-standard archive format, such as a ZIP or RAR file, or has a tarball with a non-standard organization, this variable allows to override the package infrastructure default behavior.
  • LIBFOO_CONFIGURE_CMDS lists the actions to be performed to configure the package before its compilation.
  • LIBFOO_BUILD_CMDS lists the actions to be performed to compile the package.
  • HOST_LIBFOO_INSTALL_CMDS lists the actions to be performed to install the package, when the package is a host package. The package must install its files to the directory given by $(HOST_DIR). All files, including development files such as headers should be installed, since other packages might be compiled on top of this package.
  • LIBFOO_INSTALL_TARGET_CMDS lists the actions to be performed to install the package to the target directory, when the package is a target package. The package must install its files to the directory given by $(TARGET_DIR). Only the files required for execution of the package have to be installed. Header files, static libraries and documentation will be removed again when the target filesystem is finalized.
  • LIBFOO_INSTALL_STAGING_CMDS lists the actions to be performed to install the package to the staging directory, when the package is a target package. The package must install its files to the directory given by $(STAGING_DIR). All development files should be installed, since they might be needed to compile other packages.
  • LIBFOO_INSTALL_IMAGES_CMDS lists the actions to be performed to install the package to the images directory, when the package is a target package. The package must install its files to the directory given by $(BINARIES_DIR). Only files that are binary images (aka images) that do not belong in the TARGET_DIR but are necessary for booting the board should be placed here. For example, a package should utilize this step if it has binaries which would be similar to the kernel image, bootloader or root filesystem images.
  • LIBFOO_INSTALL_INIT_SYSV and LIBFOO_INSTALL_INIT_SYSTEMD list the actions to install init scripts either for the systemV-like init systems (busybox, sysvinit, etc.) or for the systemd units. These commands will be run only when the relevant init system is installed (i.e. if systemd is selected as the init system in the configuration, only LIBFOO_INSTALL_INIT_SYSTEMD will be run).

The preferred way to define these variables is:

define LIBFOO_CONFIGURE_CMDS
        action 1
        action 2
        action 3
endef

In the action definitions, you can use the following variables:

  • $(@D), which contains the directory in which the package source code has been uncompressed.
  • $(TARGET_CC), $(TARGET_LD), etc. to get the target cross-compilation utilities
  • $(TARGET_CROSS) to get the cross-compilation toolchain prefix
  • Of course the $(HOST_DIR), $(STAGING_DIR) and $(TARGET_DIR) variables to install the packages properly.

Finally, you can also use hooks. See Section 7.2.12, “Hooks available in the various build steps” for more information.

7.2.6. Infrastructure for autotools-based packages

autotools-package tutorial

First, let’s see how to write a .mk file for an autotools-based package, with an example :

01: ################################################################################
02: #
03: # libfoo
04: #
05: ################################################################################
06:
07: LIBFOO_VERSION = 1.0
08: LIBFOO_SOURCE = libfoo-$(LIBFOO_VERSION).tar.gz
09: LIBFOO_SITE = http://www.foosoftware.org/download
10: LIBFOO_INSTALL_STAGING = YES
11: LIBFOO_INSTALL_TARGET = NO
12: LIBFOO_CONF_OPT = --disable-shared
13: LIBFOO_DEPENDENCIES = libglib2 host-pkgconf
14:
15: $(eval $(autotools-package))

On line 7, we declare the version of the package.

On line 8 and 9, we declare the name of the tarball (xz-ed tarball recommended) and the location of the tarball on the Web. Buildroot will automatically download the tarball from this location.

On line 10, we tell Buildroot to install the package to the staging directory. The staging directory, located in output/staging/ is the directory where all the packages are installed, including their development files, etc. By default, packages are not installed to the staging directory, since usually, only libraries need to be installed in the staging directory: their development files are needed to compile other libraries or applications depending on them. Also by default, when staging installation is enabled, packages are installed in this location using the make install command.

On line 11, we tell Buildroot to not install the package to the target directory. This directory contains what will become the root filesystem running on the target. For purely static libraries, it is not necessary to install them in the target directory because they will not be used at runtime. By default, target installation is enabled; setting this variable to NO is almost never needed. Also by default, packages are installed in this location using the make install command.

On line 12, we tell Buildroot to pass a custom configure option, that will be passed to the ./configure script before configuring and building the package.

On line 13, we declare our dependencies, so that they are built before the build process of our package starts.

Finally, on line line 15, we invoke the autotools-package macro that generates all the Makefile rules that actually allows the package to be built.

autotools-package reference

The main macro of the autotools package infrastructure is autotools-package. It is similar to the generic-package macro. The ability to have target and host packages is also available, with the host-autotools-package macro.

Just like the generic infrastructure, the autotools infrastructure works by defining a number of variables before calling the autotools-package macro.

First, all the package metadata information variables that exist in the generic infrastructure also exist in the autotools infrastructure: LIBFOO_VERSION, LIBFOO_SOURCE, LIBFOO_PATCH, LIBFOO_SITE, LIBFOO_SUBDIR, LIBFOO_DEPENDENCIES, LIBFOO_INSTALL_STAGING, LIBFOO_INSTALL_TARGET.

A few additional variables, specific to the autotools infrastructure, can also be defined. Many of them are only useful in very specific cases, typical packages will therefore only use a few of them.

  • LIBFOO_SUBDIR may contain the name of a subdirectory inside the package that contains the configure script. This is useful, if for example, the main configure script is not at the root of the tree extracted by the tarball. If HOST_LIBFOO_SUBDIR is not specified, it defaults to LIBFOO_SUBDIR.
  • LIBFOO_CONF_ENV, to specify additional environment variables to pass to the configure script. By default, empty.
  • LIBFOO_CONF_OPT, to specify additional configure options to pass to the configure script. By default, empty.
  • LIBFOO_MAKE, to specify an alternate make command. This is typically useful when parallel make is enabled in the configuration (using BR2_JLEVEL) but that this feature should be disabled for the given package, for one reason or another. By default, set to $(MAKE). If parallel building is not supported by the package, then it should be set to LIBFOO_MAKE=$(MAKE1).
  • LIBFOO_MAKE_ENV, to specify additional environment variables to pass to make in the build step. These are passed before the make command. By default, empty.
  • LIBFOO_MAKE_OPT, to specify additional variables to pass to make in the build step. These are passed after the make command. By default, empty.
  • LIBFOO_AUTORECONF, tells whether the package should be autoreconfigured or not (i.e. if the configure script and Makefile.in files should be re-generated by re-running autoconf, automake, libtool, etc.). Valid values are YES and NO. By default, the value is NO
  • LIBFOO_AUTORECONF_ENV, to specify additional environment variables to pass to the autoreconf program if LIBFOO_AUTORECONF=YES. These are passed in the environment of the autoreconf command. By default, empty.
  • LIBFOO_AUTORECONF_OPT to specify additional options passed to the autoreconf program if LIBFOO_AUTORECONF=YES. By default, empty.
  • LIBFOO_GETTEXTIZE, tells whether the package should be gettextized or not (i.e. if the package uses a different gettext version than Buildroot provides, and it is needed to run gettextize.) Only valid when LIBFOO_AUTORECONF=YES. Valid values are YES and NO. The default is NO.
  • LIBFOO_GETTEXTIZE_OPT, to specify additional options passed to the gettextize program, if LIBFOO_GETTEXTIZE=YES. You may use that if, for example, the .po files are not located in the standard place (i.e. in po/ at the root of the package.) By default, -f.
  • LIBFOO_LIBTOOL_PATCH tells whether the Buildroot patch to fix libtool cross-compilation issues should be applied or not. Valid values are YES and NO. By default, the value is YES
  • LIBFOO_INSTALL_STAGING_OPT contains the make options used to install the package to the staging directory. By default, the value is DESTDIR=$(STAGING_DIR) install, which is correct for most autotools packages. It is still possible to override it.
  • LIBFOO_INSTALL_TARGET_OPT contains the make options used to install the package to the target directory. By default, the value is DESTDIR=$(TARGET_DIR) install. The default value is correct for most autotools packages, but it is still possible to override it if needed.

With the autotools infrastructure, all the steps required to build and install the packages are already defined, and they generally work well for most autotools-based packages. However, when required, it is still possible to customize what is done in any particular step:

  • By adding a post-operation hook (after extract, patch, configure, build or install). See Section 7.2.12, “Hooks available in the various build steps” for details.
  • By overriding one of the steps. For example, even if the autotools infrastructure is used, if the package .mk file defines its own LIBFOO_CONFIGURE_CMDS variable, it will be used instead of the default autotools one. However, using this method should be restricted to very specific cases. Do not use it in the general case.

7.2.7. Infrastructure for CMake-based packages

cmake-package tutorial

First, let’s see how to write a .mk file for a CMake-based package, with an example :

01: ################################################################################
02: #
03: # libfoo
04: #
05: ################################################################################
06:
07: LIBFOO_VERSION = 1.0
08: LIBFOO_SOURCE = libfoo-$(LIBFOO_VERSION).tar.gz
09: LIBFOO_SITE = http://www.foosoftware.org/download
10: LIBFOO_INSTALL_STAGING = YES
11: LIBFOO_INSTALL_TARGET = NO
12: LIBFOO_CONF_OPT = -DBUILD_DEMOS=ON
13: LIBFOO_DEPENDENCIES = libglib2 host-pkgconf
14:
15: $(eval $(cmake-package))

On line 7, we declare the version of the package.

On line 8 and 9, we declare the name of the tarball (xz-ed tarball recommended) and the location of the tarball on the Web. Buildroot will automatically download the tarball from this location.

On line 10, we tell Buildroot to install the package to the staging directory. The staging directory, located in output/staging/ is the directory where all the packages are installed, including their development files, etc. By default, packages are not installed to the staging directory, since usually, only libraries need to be installed in the staging directory: their development files are needed to compile other libraries or applications depending on them. Also by default, when staging installation is enabled, packages are installed in this location using the make install command.

On line 11, we tell Buildroot to not install the package to the target directory. This directory contains what will become the root filesystem running on the target. For purely static libraries, it is not necessary to install them in the target directory because they will not be used at runtime. By default, target installation is enabled; setting this variable to NO is almost never needed. Also by default, packages are installed in this location using the make install command.

On line 12, we tell Buildroot to pass custom options to CMake when it is configuring the package.

On line 13, we declare our dependencies, so that they are built before the build process of our package starts.

Finally, on line line 15, we invoke the cmake-package macro that generates all the Makefile rules that actually allows the package to be built.

cmake-package reference

The main macro of the CMake package infrastructure is cmake-package. It is similar to the generic-package macro. The ability to have target and host packages is also available, with the host-cmake-package macro.

Just like the generic infrastructure, the CMake infrastructure works by defining a number of variables before calling the cmake-package macro.

First, all the package metadata information variables that exist in the generic infrastructure also exist in the CMake infrastructure: LIBFOO_VERSION, LIBFOO_SOURCE, LIBFOO_PATCH, LIBFOO_SITE, LIBFOO_SUBDIR, LIBFOO_DEPENDENCIES, LIBFOO_INSTALL_STAGING, LIBFOO_INSTALL_TARGET.

A few additional variables, specific to the CMake infrastructure, can also be defined. Many of them are only useful in very specific cases, typical packages will therefore only use a few of them.

  • LIBFOO_SUBDIR may contain the name of a subdirectory inside the package that contains the main CMakeLists.txt file. This is useful, if for example, the main CMakeLists.txt file is not at the root of the tree extracted by the tarball. If HOST_LIBFOO_SUBDIR is not specified, it defaults to LIBFOO_SUBDIR.
  • LIBFOO_CONF_ENV, to specify additional environment variables to pass to CMake. By default, empty.
  • LIBFOO_CONF_OPT, to specify additional configure options to pass to CMake. By default, empty.
  • LIBFOO_MAKE, to specify an alternate make command. This is typically useful when parallel make is enabled in the configuration (using BR2_JLEVEL) but that this feature should be disabled for the given package, for one reason or another. By default, set to $(MAKE). If parallel building is not supported by the package, then it should be set to LIBFOO_MAKE=$(MAKE1).
  • LIBFOO_MAKE_ENV, to specify additional environment variables to pass to make in the build step. These are passed before the make command. By default, empty.
  • LIBFOO_MAKE_OPT, to specify additional variables to pass to make in the build step. These are passed after the make command. By default, empty.
  • LIBFOO_INSTALL_STAGING_OPT contains the make options used to install the package to the staging directory. By default, the value is DESTDIR=$(STAGING_DIR) install, which is correct for most CMake packages. It is still possible to override it.
  • LIBFOO_INSTALL_TARGET_OPT contains the make options used to install the package to the target directory. By default, the value is DESTDIR=$(TARGET_DIR) install. The default value is correct for most CMake packages, but it is still possible to override it if needed.

With the CMake infrastructure, all the steps required to build and install the packages are already defined, and they generally work well for most CMake-based packages. However, when required, it is still possible to customize what is done in any particular step:

  • By adding a post-operation hook (after extract, patch, configure, build or install). See Section 7.2.12, “Hooks available in the various build steps” for details.
  • By overriding one of the steps. For example, even if the CMake infrastructure is used, if the package .mk file defines its own LIBFOO_CONFIGURE_CMDS variable, it will be used instead of the default CMake one. However, using this method should be restricted to very specific cases. Do not use it in the general case.

7.2.8. Infrastructure for Python packages

This infrastructure applies to Python packages that use the standard Python setuptools mechanism as their build system, generally recognizable by the usage of a setup.py script.

python-package tutorial

First, let’s see how to write a .mk file for a Python package, with an example :

01: ################################################################################
02: #
03: # python-foo
04: #
05: ################################################################################
06:
07: PYTHON_FOO_VERSION = 1.0
08: PYTHON_FOO_SOURCE = python-foo-$(LIBFOO_VERSION).tar.xz
09: PYTHON_FOO_SITE = http://www.foosoftware.org/download
10: PYTHON_FOO_LICENSE = BSD-3c
11: PYTHON_FOO_LICENSE_FILES = LICENSE
12: PYTHON_FOO_ENV = SOME_VAR=1
13: PYTHON_FOO_DEPENDENCIES = libmad
14: PYTHON_FOO_SETUP_TYPE = distutils
15:
16: $(eval $(python-package))

On line 7, we declare the version of the package.

On line 8 and 9, we declare the name of the tarball (xz-ed tarball recommended) and the location of the tarball on the Web. Buildroot will automatically download the tarball from this location.

On line 10 and 11, we give licensing details about the package (its license on line 10, and the file containing the license text on line 11).

On line 12, we tell Buildroot to pass custom options to the Python setup.py script when it is configuring the package.

On line 13, we declare our dependencies, so that they are built before the build process of our package starts.

On line 14, we declare the specific Python build system being used. In this case the distutils Python build system is used. The two supported ones are distutils and setuptools.

Finally, on line 16, we invoke the python-package macro that generates all the Makefile rules that actually allow the package to be built.

python-package reference

As a policy, packages that merely provide Python modules should all be named python-<something> in Buildroot. Other packages that use the Python build system, but are not Python modules, can freely choose their name (existing examples in Buildroot are scons and supervisor).

In their Config.in file, they should depend on BR2_PACKAGE_PYTHON so that when Buildroot will enable Python 3 usage for modules, we will be able to enable Python modules progressively on Python 3.

The main macro of the Python package infrastructure is python-package. It is similar to the generic-package macro. It is also possible to create Python host packages with the host-python-package macro.

Just like the generic infrastructure, the Python infrastructure works by defining a number of variables before calling the python-package or host-python-package macros.

All the package metadata information variables that exist in the generic package infrastructure the section called “generic-package reference” also exist in the Python infrastructure: PYTHON_FOO_VERSION, PYTHON_FOO_SOURCE, PYTHON_FOO_PATCH, PYTHON_FOO_SITE, PYTHON_FOO_SUBDIR, PYTHON_FOO_DEPENDENCIES, PYTHON_FOO_LICENSE, PYTHON_FOO_LICENSE_FILES, PYTHON_FOO_INSTALL_STAGING, etc.

Note that:

  • It is not necessary to add python or host-python in the PYTHON_FOO_DEPENDENCIES variable of a package, since these basic dependencies are automatically added as needed by the Python package infrastructure.
  • Similarly, it is not needed to add host-setuptools and/or host-distutilscross dependencies to PYTHON_FOO_DEPENDENCIES for setuptools-based packages, since these are automatically added by the Python infrastructure as needed.

One variable specific to the Python infrastructure is mandatory:

  • PYTHON_FOO_SETUP_TYPE, to define which Python build system is used by the package. The two supported values are distutils and setuptools. If you don’t know which one is used in your package, look at the setup.py file in your package source code, and see whether it imports things from the distutils module or the setuptools module.

A few additional variables, specific to the Python infrastructure, can optionally be defined, depending on the package’s needs. Many of them are only useful in very specific cases, typical packages will therefore only use a few of them, or none.

  • PYTHON_FOO_ENV, to specify additional environment variables to pass to the Python setup.py script (for both the build and install steps). Note that the infrastructure is automatically passing several standard variables, defined in PKG_PYTHON_DISTUTILS_ENV (for distutils target packages), HOST_PKG_PYTHON_DISTUTILS_ENV (for distutils host packages), PKG_PYTHON_SETUPTOOLS_ENV (for setuptools target packages) and HOST_PKG_PYTHON_SETUPTOOLS_ENV (for setuptools host packages).
  • PYTHON_FOO_BUILD_OPT, to specify additional options to pass to the Python setup.py script during the build step. For target distutils packages, the PKG_PYTHON_DISTUTILS_BUILD_OPT options are already passed automatically by the infrastructure.
  • PYTHON_FOO_INSTALL_TARGET_OPT, PYTHON_FOO_INSTALL_STAGING_OPT, HOST_PYTHON_FOO_INSTALL_OPT to specify additional options to pass to the Python setup.py script during the target installation step, the staging installation step or the host installation, respectively. Note that the infrastructure is automatically passing some options, defined in PKG_PYTHON_DISTUTILS_INSTALL_TARGET_OPT or PKG_PYTHON_DISTUTILS_INSTALL_STAGING_OPT (for target distutils packages), HOST_PKG_PYTHON_DISTUTILS_INSTALL_OPT (for host distutils packages), PKG_PYTHON_SETUPTOOLS_INSTALL_TARGET_OPT or PKG_PYTHON_SETUPTOOLS_INSTALL_STAGING_OPT (for target setuptools packages) and HOST_PKG_PYTHON_SETUPTOOLS_INSTALL_OPT (for host setuptools packages).
  • HOST_PYTHON_FOO_NEEDS_HOST_PYTHON, to define the host python interpreter. The usage of this variable is limited to host packages. The two supported value are python2 and python3. It will ensures the right host python package is available and will invoke it for the build. If some build steps are overloaded, the right python interpreter must be explicitly called in the commands.

With the Python infrastructure, all the steps required to build and install the packages are already defined, and they generally work well for most Python-based packages. However, when required, it is still possible to customize what is done in any particular step:

  • By adding a post-operation hook (after extract, patch, configure, build or install). See Section 7.2.12, “Hooks available in the various build steps” for details.
  • By overriding one of the steps. For example, even if the Python infrastructure is used, if the package .mk file defines its own PYTHON_FOO_BUILD_CMDS variable, it will be used instead of the default Python one. However, using this method should be restricted to very specific cases. Do not use it in the general case.

7.2.9. Infrastructure for LuaRocks-based packages

luarocks-package tutorial

First, let’s see how to write a .mk file for a LuaRocks-based package, with an example :

01: ################################################################################
02: #
03: # luafoo
04: #
05: ################################################################################
06:
07: LUAFOO_VERSION = 1.0.2-1
08: LUAFOO_DEPENDENCIES = foo
09:
10: LUAFOO_BUILD_OPT += FOO_INCDIR=$(STAGING_DIR)/usr/include
11: LUAFOO_BUILD_OPT += FOO_LIBDIR=$(STAGING_DIR)/usr/lib
12: LUAFOO_LICENSE = luaFoo license
13: LUAFOO_LICENSE_FILES = COPYING
14:
15: $(eval $(luarocks-package))

On line 7, we declare the version of the package (the same as in the rockspec, which is the concatenation of the upstream version and the rockspec revision, separated by a hyphen -).

On line 8, we declare our dependencies against native libraries, so that they are built before the build process of our package starts.

On lines 10-11, we tell Buildroot to pass custom options to LuaRocks when it is building the package.

On lines 12-13, we specify the licensing terms for the package.

Finally, on line 15, we invoke the luarocks-package macro that generates all the Makefile rules that actually allows the package to be built.

luarocks-package reference

LuaRocks is a deployment and management system for Lua modules, and supports various build.type: builtin, make and cmake. In the context of Buildroot, the luarocks-package infrastructure only supports the builtin mode. LuaRocks packages that use the make or cmake build mechanisms should instead be packaged using the generic-package and cmake-package infrastructures in Buildroot, respectively.

The main macro of the LuaRocks package infrastructure is luarocks-package: like generic-package it works by defining a number of variables providing metadata information about the package, and then calling luarocks-package. It is worth mentioning that building LuaRocks packages for the host is not supported, so the macro host-luarocks-package is not implemented.

Just like the generic infrastructure, the LuaRocks infrastructure works by defining a number of variables before calling the luarocks-package macro.

First, all the package metadata information variables that exist in the generic infrastructure also exist in the LuaRocks infrastructure: LUAFOO_VERSION, LUAFOO_SOURCE, LUAFOO_SITE, LUAFOO_DEPENDENCIES, LUAFOO_LICENSE, LUAFOO_LICENSE_FILES.

Two of them are populated by the LuaRocks infrastructure (for the download step). If your package is not hosted on the LuaRocks mirror $(BR2_LUAROCKS_MIRROR), you can override them:

  • LUAFOO_SITE, which defaults to $(BR2_LUAROCKS_MIRROR)
  • LUAFOO_SOURCE, which defaults to luafoo-$(LUAFOO_VERSION).src.rock

A few additional variables, specific to the LuaRocks infrastructure, are also defined. They can be overridden in specific cases.

  • LUAFOO_ROCKSPEC, which defaults to luafoo-$(LUAFOO_VERSION).rockspec
  • LUAFOO_SUBDIR, which defaults to luafoo-$(LUAFOO_VERSION_WITHOUT_ROCKSPEC_REVISION)
  • LUAFOO_BUILD_OPT contains additional build options for the luarocks build call.

7.2.10. Infrastructure for Perl/CPAN packages

perl-package tutorial

First, let’s see how to write a .mk file for a Perl/CPAN package, with an example :

01: ################################################################################
02: #
03: # perl-foo-bar
04: #
05: ################################################################################
06:
07: PERL_FOO_BAR_VERSION = 0.02
08: PERL_FOO_BAR_SOURCE = Foo-Bar-$(PERL_FOO_BAR_VERSION).tar.gz
09: PERL_FOO_BAR_SITE = $(BR2_CPAN_MIRROR)/authors/id/M/MO/MONGER/
10: PERL_FOO_BAR_DEPENDENCIES = perl-strictures
11: PERL_FOO_BAR_LICENSE = Artistic or GPLv1+
12: PERL_FOO_BAR_LICENSE_FILES = LICENSE
13:
14: $(eval $(perl-package))

On line 7, we declare the version of the package.

On line 8 and 9, we declare the name of the tarball and the location of the tarball on a CPAN server. Buildroot will automatically download the tarball from this location.

On line 10, we declare our dependencies, so that they are built before the build process of our package starts.

On line 11 and 12, we give licensing details about the package (its license on line 11, and the file containing the license text on line 12).

Finally, on line 14, we invoke the perl-package macro that generates all the Makefile rules that actually allow the package to be built.

Most of these data can be retrieved from https://metacpan.org/. So, this file and the Config.in can be generated by running the script supports/scripts/scancpan Foo-Bar in the Buildroot directory (or in the BR2_EXTERNAL directory). This script creates a Config.in file and foo-bar.mk file for the requested package, and also recursively for all dependencies specified by CPAN. You should still manually edit the result. In particular, the following things should be checked.

  • If the perl module links with a shared library that is provided by another (non-perl) package, this dependency is not added automatically. It has to be added manually to PERL_FOO_BAR_DEPENDENCIES.
  • The package/Config.in file has to be updated manually to include the generated Config.in files. As a hint, the scancpan script prints out the required source "…" statements, sorted alphabetically.

perl-package reference

As a policy, packages that provide Perl/CPAN modules should all be named perl-<something> in Buildroot.

This infrastructure handles various Perl build systems : ExtUtils-MakeMaker, Module-Build and Module-Build-Tiny. Build.PL is always preferred when a package provides a Makefile.PL and a Build.PL.

The main macro of the Perl/CPAN package infrastructure is perl-package. It is similar to the generic-package macro. The ability to have target and host packages is also available, with the host-perl-package macro.

Just like the generic infrastructure, the Perl/CPAN infrastructure works by defining a number of variables before calling the perl-package macro.

First, all the package metadata information variables that exist in the generic infrastructure also exist in the Perl/CPAN infrastructure: PERL_FOO_VERSION, PERL_FOO_SOURCE, PERL_FOO_PATCH, PERL_FOO_SITE, PERL_FOO_SUBDIR, PERL_FOO_DEPENDENCIES, PERL_FOO_INSTALL_TARGET.

Note that setting PERL_FOO_INSTALL_STAGING to YES has no effect unless a PERL_FOO_INSTALL_STAGING_CMDS variable is defined. The perl infrastructure doesn’t define these commands since Perl modules generally don’t need to be installed to the staging directory.

A few additional variables, specific to the Perl/CPAN infrastructure, can also be defined. Many of them are only useful in very specific cases, typical packages will therefore only use a few of them.

  • PERL_FOO_CONF_ENV/HOST_PERL_FOO_CONF_ENV, to specify additional environment variables to pass to the perl Makefile.PL or perl Build.PL. By default, empty.
  • PERL_FOO_CONF_OPT/HOST_PERL_FOO_CONF_OPT, to specify additional configure options to pass to the perl Makefile.PL or perl Build.PL. By default, empty.
  • PERL_FOO_BUILD_OPT/HOST_PERL_FOO_BUILD_OPT, to specify additional options to pass to make pure_all or perl Build build in the build step. By default, empty.
  • PERL_FOO_INSTALL_TARGET_OPT, to specify additional options to pass to make pure_install or perl Build install in the install step. By default, empty.
  • HOST_PERL_FOO_INSTALL_OPT, to specify additional options to pass to make pure_install or perl Build install in the install step. By default, empty.

7.2.11. Infrastructure for virtual packages

In Buildroot, a virtual package is a package whose functionalities are provided by one or more packages, referred to as providers. The virtual package management is an extensible mechanism allowing the user to choose the provider used in the rootfs.

For example, OpenGL ES is an API for 2D and 3D graphics on embedded systems. The implementation of this API is different for the Allwinner Tech Sunxi and the Texas Instruments OMAP35xx platforms. So libgles will be a virtual package and sunxi-mali and ti-gfx will be the providers.

virtual-package tutorial

In the following example, we will explain how to add a new virtual package (something-virtual) and a provider for it (some-provider).

First, let’s create the virtual package.

Virtual package’s Config.in file

The Config.in file of virtual package something-virtual should contain:

01: config BR2_PACKAGE_HAS_SOMETHING_VIRTUAL
02:     bool
03:
04: config BR2_PACKAGE_PROVIDES_SOMETHING_VIRTUAL
05:     depends on BR2_PACKAGE_HAS_SOMETHING_VIRTUAL
06:     string

In this file, we declare two options, BR2_PACKAGE_HAS_SOMETHING_VIRTUAL and BR2_PACKAGE_PROVIDES_SOMETHING_VIRTUAL, whose values will be used by the providers.

Virtual package’s .mk file

The .mk for the virtual package should just evaluate the virtual-package macro:

01: ################################################################################
02: #
03: # something-virtual
04: #
05: ################################################################################
06:
07: $(eval $(virtual-package))

The ability to have target and host packages is also available, with the host-virtual-package macro.

Provider’s Config.in file

When adding a package as a provider, only the Config.in file requires some modifications.

The Config.in file of the package some-provider, which provides the functionalities of something-virtual, should contain:

01: config BR2_PACKAGE_SOME_PROVIDER
02:     bool "some-provider"
03:     select BR2_PACKAGE_HAS_SOMETHING_VIRTUAL
04:     help
05:       This is a comment that explains what some-provider is.
06:
07:       http://foosoftware.org/some-provider/
08:
09: if BR2_PACKAGE_SOME_PROVIDER
10: config BR2_PACKAGE_PROVIDES_SOMETHING_VIRTUAL
11:     default "some-provider"
12: endif

On line 3, we select BR2_PACKAGE_HAS_SOMETHING_VIRTUAL, and on line 11, we set the value of BR2_PACKAGE_PROVIDES_SOMETHING_VIRTUAL to the name of the provider, but only if it is selected.

See Section 12.4, “List of virtual packages” for the symbols to select if you implement a new provider for an existing virtual package.

Provider’s .mk file

The .mk file should also declare an additional variable SOME_PROVIDER_PROVIDES to contain the names of all the virtual packages it is an implementation of:

01: SOME_PROVIDER_PROVIDES = something-virtual

Of course, do not forget to add the proper build and runtime dependencies for this package!

See Section 12.4, “List of virtual packages” for the names of virtual packages to provide if you implement a new provider for an existing virtual package.

Notes on depending on a virtual package

When adding a package that requires a certain FEATURE provided by a virtual package, you have to use depends on BR2_PACKAGE_HAS_FEATURE, like so:

config BR2_PACKAGE_HAS_FEATURE
    bool

config BR2_PACKAGE_FOO
    bool "foo"
    depends on BR2_PACKAGE_HAS_FEATURE

Notes on depending on a specific provider

If your package really requires a specific provider, then you’ll have to make your package depends on this provider; you can not select a provider.

Let’s take an example with two providers for a FEATURE:

config BR2_PACKAGE_HAS_FEATURE
    bool

config BR2_PACKAGE_FOO
    bool "foo"
    select BR2_PACKAGE_HAS_FEATURE

config BR2_PACKAGE_BAR
    bool "bar"
    select BR2_PACKAGE_HAS_FEATURE

And you are adding a package that needs FEATURE as provided by foo, but not as provided by bar.

If you were to use select BR2_PACKAGE_FOO, then the user would still be able to select BR2_PACKAGE_BAR in the menuconfig. This would create a configuration inconsistency, whereby two providers of the same FEATURE would be enabled at once, one explicitly set by the user, the other implicitly by your select.

Instead, you have to use depends on BR2_PACKAGE_FOO, which avoids any implicit configuration inconsistency.

7.2.12. Hooks available in the various build steps

The generic infrastructure (and as a result also the derived autotools and cmake infrastructures) allow packages to specify hooks. These define further actions to perform after existing steps. Most hooks aren’t really useful for generic packages, since the .mk file already has full control over the actions performed in each step of the package construction.

The following hook points are available:

  • LIBFOO_PRE_DOWNLOAD_HOOKS
  • LIBFOO_POST_DOWNLOAD_HOOKS
  • LIBFOO_PRE_EXTRACT_HOOKS
  • LIBFOO_POST_EXTRACT_HOOKS
  • LIBFOO_PRE_RSYNC_HOOKS
  • LIBFOO_POST_RSYNC_HOOKS
  • LIBFOO_PRE_PATCH_HOOKS
  • LIBFOO_POST_PATCH_HOOKS
  • LIBFOO_PRE_CONFIGURE_HOOKS
  • LIBFOO_POST_CONFIGURE_HOOKS
  • LIBFOO_PRE_BUILD_HOOKS
  • LIBFOO_POST_BUILD_HOOKS
  • LIBFOO_PRE_INSTALL_HOOKS (for host packages only)
  • LIBFOO_POST_INSTALL_HOOKS (for host packages only)
  • LIBFOO_PRE_INSTALL_STAGING_HOOKS (for target packages only)
  • LIBFOO_POST_INSTALL_STAGING_HOOKS (for target packages only)
  • LIBFOO_PRE_INSTALL_TARGET_HOOKS (for target packages only)
  • LIBFOO_POST_INSTALL_TARGET_HOOKS (for target packages only)
  • LIBFOO_PRE_INSTALL_IMAGES_HOOKS
  • LIBFOO_POST_INSTALL_IMAGES_HOOKS
  • LIBFOO_PRE_LEGAL_INFO_HOOKS
  • LIBFOO_POST_LEGAL_INFO_HOOKS

These variables are lists of variable names containing actions to be performed at this hook point. This allows several hooks to be registered at a given hook point. Here is an example:

define LIBFOO_POST_PATCH_FIXUP
        action1
        action2
endef

LIBFOO_POST_PATCH_HOOKS += LIBFOO_POST_PATCH_FIXUP

Using the POST_RSYNC hook

The POST_RSYNC hook is run only for packages that use a local source, either through the local site method or the OVERRIDE_SRCDIR mechanism. In this case, package sources are copied using rsync from the local location into the buildroot build directory. The rsync command does not copy all files from the source directory, though. Files belonging to a version control system, like the directories .git, .hg, etc. are not copied. For most packages this is sufficient, but a given package can perform additional actions using the POST_RSYNC hook.

In principle, the hook can contain any command you want. One specific use case, though, is the intentional copying of the version control directory using rsync. The rsync command you use in the hook can, among others, use the following variables:

  • $(SRCDIR): the path to the overridden source directory
  • $(@D): the path to the build directory

7.2.13. Gettext integration and interaction with packages

Many packages that support internationalization use the gettext library. Dependencies for this library are fairly complicated and therefore, deserve some explanation.

The uClibc C library doesn’t implement gettext functionality; therefore with this C library, a separate gettext must be compiled. On the other hand, the glibc C library does integrate its own gettext, and in this case the separate gettext library should not be compiled, because it creates various kinds of build failures.

Additionally, some packages (such as libglib2) do require gettext unconditionally, while other packages (those who support --disable-nls in general) only require gettext when locale support is enabled.

Therefore, Buildroot defines two configuration options:

  • BR2_NEEDS_GETTEXT, which is true as soon as the toolchain doesn’t provide its own gettext implementation
  • BR2_NEEDS_GETTEXT_IF_LOCALE, which is true if the toolchain doesn’t provide its own gettext implementation and if locale support is enabled

Packages that need gettext only when locale support is enabled should:

  • use select BR2_PACKAGE_GETTEXT if BR2_NEEDS_GETTEXT_IF_LOCALE in the Config.in file;
  • use $(if $(BR2_NEEDS_GETTEXT_IF_LOCALE),gettext) in the package DEPENDENCIES variable in the .mk file.

Packages that unconditionally need gettext (which should be very rare) should:

  • use select BR2_PACKAGE_GETTEXT if BR2_NEEDS_GETTEXT in the Config.in file;
  • use $(if $(BR2_NEEDS_GETTEXT),gettext) in the package DEPENDENCIES variable in the .mk file.

7.2.14. Tips and tricks

Package name, config entry name and makefile variable relationship

In Buildroot, there is some relationship between:

  • the package name, which is the package directory name (and the name of the *.mk file);
  • the config entry name that is declared in the Config.in file;
  • the makefile variable prefix.

It is mandatory to maintain consistency between these elements, using the following rules:

  • the package directory and the *.mk name are the package name itself (e.g.: package/foo-bar_boo/foo-bar_boo.mk);
  • the make target name is the package name itself (e.g.: foo-bar_boo);
  • the config entry is the upper case package name with . and - characters substituted with _, prefixed with BR2_PACKAGE_ (e.g.: BR2_PACKAGE_FOO_BAR_BOO);
  • the *.mk file variable prefix is the upper case package name with . and - characters substituted with _ (e.g.: FOO_BAR_BOO_VERSION).

How to add a package from GitHub

Packages on GitHub often don’t have a download area with release tarballs. However, it is possible to download tarballs directly from the repository on GitHub. As GitHub is known to have changed download mechanisms in the past, the github helper function should be used as shown below.

FOO_VERSION = v1.0 # tag or full commit ID
FOO_SITE = $(call github,<user>,<package>,$(FOO_VERSION))

Notes

  • The FOO_VERSION can either be a tag or a commit ID.
  • The tarball name generated by github matches the default one from Buildroot (e.g.: foo-f6fb6654af62045239caed5950bc6c7971965e60.tar.gz), so it is not necessary to specify it in the .mk file.
  • When using a commit ID as version, you should use the full 40 hex characters.

7.2.15. Conclusion

As you can see, adding a software package to Buildroot is simply a matter of writing a Makefile using an existing example and modifying it according to the compilation process required by the package.

If you package software that might be useful for other people, don’t forget to send a patch to the Buildroot mailing list (see Section 11.5, “Submitting patches”)!

7.3. Patching a package

While integrating a new package or updating an existing one, it may be necessary to patch the source of the software to get it cross-built within Buildroot.

Buildroot offers an infrastructure to automatically handle this during the builds. It supports three ways of applying patch sets: downloaded patches, patches supplied within buildroot and patches located in a user-defined global patch directory.

7.3.1. Providing patches

Downloaded

If it is necessary to apply a patch that is available for download, then add it to the <packagename>_PATCH variable. It is downloaded from the same site as the package itself. It can be a single patch, or a tarball containing a patch series.

This method is typically used for packages from Debian.

Within Buildroot

Most patches are provided within Buildroot, in the package directory; these typically aim to fix cross-compilation, libc support, or other such issues.

These patch files should be named <packagename>-<number>-<description>.patch.

A series file, as used by quilt, may also be added in the package directory. In that case, the series file defines the patch application order.

Notes

  • The patch files coming with Buildroot should not contain any package version reference in their filename.
  • The field <number> in the patch file name refers to the apply order.

Global patch directory

The BR2_GLOBAL_PATCH_DIR configuration file option can be used to specify a space separated list of one or more directories containing global package patches. See Section 3.4.4, “Customizing packages” for details.

7.3.2. How patches are applied

  1. Run the <packagename>_PRE_PATCH_HOOKS commands if defined;
  2. Cleanup the build directory, removing any existing *.rej files;
  3. If <packagename>_PATCH is defined, then patches from these tarballs are applied;
  4. If there are some *.patch files in the package’s Buildroot directory or in a package subdirectory named <packageversion>, then:

    • If a series file exists in the package directory, then patches are applied according to the series file;
    • Otherwise, patch files matching <packagename>-*.patch are applied in alphabetical order. So, to ensure they are applied in the right order, it is highly recommended to name the patch files like this: <packagename>-<number>-<description>.patch, where <number> refers to the apply order.
  5. If BR2_GLOBAL_PATCH_DIR is defined, the directories will be enumerated in the order they are specified. The patches are applied as described in the previous step.
  6. Run the <packagename>_POST_PATCH_HOOKS commands if defined.

If something goes wrong in the steps 3 or 4, then the build fails.

7.3.3. Format and licensing of the package patches

Patches are released under the same license as the software that is modified.

A message explaining what the patch does, and why it is needed, should be added in the header commentary of the patch.

You should add a Signed-off-by statement in the header of the each patch to help with keeping track of the changes and to certify that the patch is released under the same license as the software that is modified.

If the software is under version control, it is recommended to use the upstream SCM software to generate the patch set.

Otherwise, concatenate the header with the output of the diff -purN package-version.orig/ package-version/ command.

At the end, the patch should look like:

configure.ac: add C++ support test

Signed-off-by: John Doe <john.doe@noname.org>

--- configure.ac.orig
+++ configure.ac
@@ -40,2 +40,12 @@

AC_PROG_MAKE_SET
+
+AC_CACHE_CHECK([whether the C++ compiler works],
+               [rw_cv_prog_cxx_works],
+               [AC_LANG_PUSH([C++])
+                AC_LINK_IFELSE([AC_LANG_PROGRAM([], [])],
+                               [rw_cv_prog_cxx_works=yes],
+                               [rw_cv_prog_cxx_works=no])
+                AC_LANG_POP([C++])])
+
+AM_CONDITIONAL([CXX_WORKS], [test "x$rw_cv_prog_cxx_works" = "xyes"])

7.3.4. Integrating patches found on the Web

When integrating a patch of which you are not the author, you have to add a few things in the header of the patch itself.

Depending on whether the patch has been obtained from the project repository itself, or from somewhere on the web, add one of the following tags:

Backported from: <some commit id>

or

Fetch from: <some url>

It is also sensible to add a few words about any changes to the patch that may have been necessary.

7.4. Download infrastructure

TODO

7.5. Debugging Buildroot

It is possible to instrument the steps Buildroot does when building packages. Define the variable BR2_INSTRUMENTATION_SCRIPTS to contain the path of one or more scripts (or other executables), in a space-separated list, you want called before and after each step. The scripts are called in sequence, with three parameters:

  • start or end to denote the start (resp. the end) of a step;
  • the name of the step about to be started, or which just ended.
  • the name of the package

For example :

make BR2_INSTRUMENTATION_SCRIPTS="/path/to/my/script1 /path/to/my/script2"

That script has access to the following variables:

  • BR2_CONFIG: the path to the Buildroot .config file
  • HOST_DIR, STAGING_DIR, TARGET_DIR: see the section called “generic-package reference”
  • BUILD_DIR: the directory where packages are extracted and built
  • BINARIES_DIR: the place where all binary files (aka images) are stored
  • BASE_DIR: the base output directory

Chapter 8. Legal notice and licensing

8.1. Complying with open source licenses

All of the end products of Buildroot (toolchain, root filesystem, kernel, bootloaders) contain open source software, released under various licenses.

Using open source software gives you the freedom to build rich embedded systems, choosing from a wide range of packages, but also imposes some obligations that you must know and honour. Some licenses require you to publish the license text in the documentation of your product. Others require you to redistribute the source code of the software to those that receive your product.

The exact requirements of each license are documented in each package, and it is your responsibility (or that of your legal office) to comply with those requirements. To make this easier for you, Buildroot can collect for you some material you will probably need. To produce this material, after you have configured Buildroot with make menuconfig, make xconfig or make gconfig, run:

make legal-info

Buildroot will collect legally-relevant material in your output directory, under the legal-info/ subdirectory. There you will find:

  • A README file, that summarizes the produced material and contains warnings about material that Buildroot could not produce.
  • buildroot.config: this is the Buildroot configuration file that is usually produced with make menuconfig, and which is necessary to reproduce the build.
  • The source code for all packages; this is saved in the sources/ and host-sources/ subdirectories for target and host packages respectively. The source code for packages that set <PKG>_REDISTRIBUTE = NO will not be saved. Patches applied to some packages by Buildroot are distributed with the Buildroot sources and are not duplicated in the sources/ and host-sources/ subdirectories.
  • A manifest file (one for host and one for target packages) listing the configured packages, their version, license and related information. Some of this information might not be defined in Buildroot; such items are marked as "unknown".
  • The license texts of all packages, in the licenses/ and host-licenses/ subdirectories for target and host packages respectively. If the license file(s) are not defined in Buildroot, the file is not produced and a warning in the README indicates this.

Please note that the aim of the legal-info feature of Buildroot is to produce all the material that is somehow relevant for legal compliance with the package licenses. Buildroot does not try to produce the exact material that you must somehow make public. Certainly, more material is produced than is needed for a strict legal compliance. For example, it produces the source code for packages released under BSD-like licenses, that you are not required to redistribute in source form.

Moreover, due to technical limitations, Buildroot does not produce some material that you will or may need, such as the toolchain source code and the Buildroot source code itself (including patches to packages for which source distribution is required). When you run make legal-info, Buildroot produces warnings in the README file to inform you of relevant material that could not be saved.

8.2. License abbreviations

Here is a list of the licenses that are most widely used by packages in Buildroot, with the name used in the manifest files:

8.3. Complying with the Buildroot license

Buildroot itself is an open source software, released under the GNU General Public License, version 2 or (at your option) any later version. However, being a build system, it is not normally part of the end product: if you develop the root filesystem, kernel, bootloader or toolchain for a device, the code of Buildroot is only present on the development machine, not in the device storage.

Nevertheless, the general view of the Buildroot developers is that you should release the Buildroot source code along with the source code of other packages when releasing a product that contains GPL-licensed software. This is because the GNU GPL defines the "complete source code" for an executable work as "all the source code for all modules it contains, plus any associated interface definition files, plus the scripts used to control compilation and installation of the executable". Buildroot is part of the scripts used to control compilation and installation of the executable, and as such it is considered part of the material that must be redistributed.

Keep in mind that this is only the Buildroot developers' opinion, and you should consult your legal department or lawyer in case of any doubt.

Chapter 9. Beyond Buildroot

9.1. Boot the generated images

9.1.1. NFS boot

To achieve NFS-boot, enable tar root filesystem in the Filesystem images menu.

After a complete build, just run the following commands to setup the NFS-root directory:

sudo tar -xavf /path/to/output_dir/rootfs.tar -C /path/to/nfs_root_dir

Remember to add this path to /etc/exports.

Then, you can execute a NFS-boot from your target.

9.2. Chroot

If you want to chroot in a generated image, then there are few thing you should be aware of:

  • you should setup the new root from the tar root filesystem image;
  • either the selected target architecture is compatible with your host machine, or you should use some qemu-* binary and correctly set it within the binfmt properties to be able to run the binaries built for the target on your host machine;
  • Buildroot does not currently provide host-qemu and binfmt correctly built and set for that kind of use.

Chapter 10. Getting involved

Like any open source project, Buildroot has different ways to share information in its community and outside.

One piece of it is the document you are currently reading ;-).

Each of those ways may interest you if you are looking for some help, want to understand Buildroot or contribute to the project.

10.1. Mailing List

Buildroot has a mailing list http://lists.busybox.net/pipermail/buildroot for discussion and development.

10.1.1. Subscribing to the mailing list

You can subscribe by visiting http://lists.busybox.net/mailman/listinfo/buildroot. Only subscribers to the Buildroot mailing list are allowed to post to this list.

The list is also available through Gmane http://gmane.org, at gmane.comp.lib.uclibc.buildroot http://dir.gmane.org/gmane.comp.lib.uclibc.buildroot.

10.1.2. Searching the List Archives

Please search the mailing list archives before asking questions on the mailing list, since there is a good chance someone else has asked the same question before. Checking the archives is a great way to avoid annoying everyone on the list with frequently asked questions…

10.2. IRC

The Buildroot IRC is irc://freenode.net/#buildroot. The channel #buildroot is hosted on Freenode http://webchat.freenode.net.

When asking for help on IRC, share relevant logs or pieces of code using a code sharing website.

10.3. Patchwork

Patchwork is a web-based patch tracking system designed to facilitate the contribution and management of contributions to an open-source project. Patches that have been sent to a mailing list are 'caught' by the system, and appear on a web page. Any comments posted that reference the patch are appended to the patch page too. For more information on Patchwork see http://jk.ozlabs.org/projects/patchwork.

Buildroot’s Patchwork website is mainly for use by Buildroot’s maintainer to ensure patches aren’t missed. The website however, exposes patches and their corresponding review comments in a clean and concise web interface.

The Buildroot patch management interface is available at http://patchwork.buildroot.org.

10.3.1. Applying Patches from Patchwork

The main use of Buildroot’s Patchwork website for a developer is for pulling in patches into their local git repository for testing purposes.

When browsing patches in the patchwork management interface, an mbox link is provided at the top of the page. Copy this link address and run the following commands:

$ git checkout -b <test-branch-name>
$ wget -O - <mbox-url> | git am

Another option for applying patches is to create a bundle. A bundle is a set of patches that you can group together using the patchwork interface. Once the bundle is created and the bundle is made public, you can copy the mbox link for the bundle and apply the bundle using the above commands.

10.4. Bugtracker

The Buildroot bugtracker is at https://bugs.busybox.net.

To open a bug, see Section 11.6, “Reporting issues/bugs or getting help”.

10.5. Buildroot wikipage

After the Buildroot developer day on February 3, 2012, a page dedicated to Buildroot has been created on elinux.org.

This page is reachable at http://elinux.org/Buildroot.

Currently, this page is mainly used as a todo-list.

10.6. Events

10.6.1. Buildroot Developer Days aside ELC-E 2012 (November 3-4, 2012 - Barcelona)

10.6.2. Buildroot presentation at LSM 2012 (July 12-14, 2012 - Geneva)

10.6.3. Buildroot Developer Days aside FOSDEM 2012 (February 3, 2012 - Brussels)

Chapter 11. Contributing to Buildroot

There are many ways in which you can contribute to Buildroot: analyzing and fixing bugs, analyzing and fixing package build failures detected by the autobuilders, testing and reviewing patches sent by other developers, working on the items in our TODO list and sending your own improvements to Buildroot or its manual. The following sections give a little more detail on each of these items.

If you are interested in contributing to Buildroot, the first thing you should do is to subscribe to the Buildroot mailing list. This list is the main way of interacting with other Buildroot developers and to send contributions to. If you aren’t subscribed yet, then refer to Section 10.1.1, “Subscribing to the mailing list”.

If you are going to touch the code, it is highly recommended to use a git repository of Buildroot, rather than starting from an extracted source code tarball. Git is the easiest way to develop from and directly send your patches to the mailing list. Refer to Section 2.2, “Getting Buildroot” for more information on obtaining a Buildroot git tree.

11.1. Reproducing, analyzing and fixing bugs

A first way of contributing is to have a look at the open bug reports in the Buildroot bug tracker. As we strive to keep the bug count as small as possible, all help in reproducing, analyzing and fixing reported bugs is more than welcome. Don’t hesitate to add a comment to bug reports reporting your findings, even if you don’t yet see the full picture.

11.2. Analyzing and fixing autobuild failures

The Buildroot autobuilders are a set of build machines that continuously run Buildroot builds based on random configurations. This is done for all architectures supported by Buildroot, with various toolchains, and with a random selection of packages. With the large commit activity on Buildroot, these autobuilders are a great help in detecting problems very early after commit.

All build results are available at http://autobuild.buildroot.org, statistics are at http://autobuild.buildroot.org/stats.php. Every day, an overview of all failed packages is sent to the mailing list.

Detecting problems is great, but obviously these problems have to be fixed as well. Your contribution is very welcome here! There are basically two things that can be done:

  • Analyzing the problems. The daily summary mails do not contain details about the actual failures: in order to see what’s going on you have to open the build log and check the last output. Having someone doing this for all packages in the mail is very useful for other developers, as they can make a quick initial analysis based on this output alone.
  • Fixing a problem. When fixing autobuild failures, you should follow these steps:

    1. Check if you can reproduce the problem by building with the same configuration. You can do this manually, or use the br-reproduce-build script that will automatically clone a Buildroot git repository, checkout the correct revision, download and set the right configuration, and start the build.
    2. Analyze the problem and create a fix.
    3. Verify that the problem is really fixed by starting from a clean Buildroot tree and only applying your fix.
    4. Send the fix to the Buildroot mailing list (see Section 11.5, “Submitting patches”). In case you created a patch against the package sources, you should also send the patch upstream so that the problem will be fixed in a later release, and the patch in Buildroot can be removed. In the commit message of a patch fixing an autobuild failure, add a reference to the build result directory, as follows:
Fixes http://autobuild.buildroot.org/results/51000a9d4656afe9e0ea6f07b9f8ed374c2e4069

11.3. Reviewing and testing patches

With the amount of patches sent to the mailing list each day, the maintainer has a very hard job to judge which patches are ready to apply and which ones aren’t. Contributors can greatly help here by reviewing and testing these patches.

In the review process, do not hesitate to respond to patch submissions for remarks, suggestions or anything that will help everyone to understand the patches and make them better. Please use internet style replies in plain text emails when responding to patch submissions.

To indicate approval of a patch, there are three formal tags that keep track of this approval. To add your tag to a patch, reply to it with the approval tag below the original author’s Signed-off-by line. These tags will be picked up automatically by patchwork (see Section 10.3.1, “Applying Patches from Patchwork”) and will be part of the commit log when the patch is accepted.

Tested-by
Indicates that the patch has been tested successfully. You are encouraged to specify what kind of testing you performed (compile-test on architecture X and Y, runtime test on target A, …). This additional information helps other testers and the maintainer.
Reviewed-by
Indicates that you code-reviewed the patch and did your best in spotting problems, but you are not sufficiently familiar with the area touched to provide an Acked-by tag. This means that there may be remaining problems in the patch that would be spotted by someone with more experience in that area. Should such problems be detected, your Reviewed-by tag remains appropriate and you cannot be blamed.
Acked-by
Indicates that you code-reviewed the patch and you are familiar enough with the area touched to feel that the patch can be committed as-is (no additional changes required). In case it later turns out that something is wrong with the patch, your Acked-by could be considered inappropriate. The difference between Acked-by and Reviewed-by is thus mainly that you are prepared to take the blame on Acked patches, but not on Reviewed ones.

If you reviewed a patch and have comments on it, you should simply reply to the patch stating these comments, without providing a Reviewed-by or Acked-by tag. These tags should only be provided if you judge the patch to be good as it is.

It is important to note that neither Reviewed-by nor Acked-by imply that testing has been performed. To indicate that you both reviewed and tested the patch, provide two separate tags (Reviewed/Acked-by and Tested-by).

Note also that any developer can provide Tested/Reviewed/Acked-by tags, without exception, and we encourage everyone to do this. Buildroot does not have a defined group of core developers, it just so happens that some developers are more active than others. The maintainer will value tags according to the track record of their submitter. Tags provided by a regular contributor will naturally be trusted more than tags provided by a newcomer. As you provide tags more regularly, your trustworthiness (in the eyes of the maintainer) will go up, but any tag provided is valuable.

Buildroot’s Patchwork website can be used to pull in patches for testing purposes. Please see Section 10.3.1, “Applying Patches from Patchwork” for more information on using Buildroot’s Patchwork website to apply patches.

11.4. Work on items from the TODO list

If you want to contribute to Buildroot but don’t know where to start, and you don’t like any of the above topics, you can always work on items from the Buildroot TODO list. Don’t hesitate to discuss an item first on the mailing list or on IRC. Do edit the wiki to indicate when you start working on an item, so we avoid duplicate efforts.

11.5. Submitting patches

Note

Please, do not attach patches to bugs, send them to the mailing list instead.

If you made some changes to Buildroot and you would like to contribute them to the Buildroot project, proceed as follows. Starting from the changes committed in your local git view, rebase your development branch on top of the upstream tree before generating a patch set. To do so, run:

$ git fetch --all --tags
$ git rebase origin/master

Now, you are ready to generate then submit your patch set.

To generate it, run:

$ git format-patch -M -n -s -o outgoing origin/master

This will generate patch files in the outgoing subdirectory, automatically adding the Signed-off-by line.

Once patch files are generated, you can review/edit the commit message before submitting them, using your favorite text editor.

Lastly, send/submit your patch set to the Buildroot mailing list:

$ git send-email --to buildroot@buildroot.org outgoing/*

Note that git should be configured to use your mail account. To configure git, see man git-send-email or google it.

If you do not use git send-email, make sure posted patches are not line-wrapped, otherwise they cannot easily be applied. In such a case, fix your e-mail client, or better yet, learn to use git send-email.

11.5.1. Cover letter

If you want to present the whole patch set in a separate mail, add --cover-letter to the git format-patch command (see man git-format-patch for further information). This will generate a template for an introduction e-mail to your patch series.

A cover letter may be useful to introduce the changes you propose in the following cases:

  • large number of commits in the series;
  • deep impact of the changes in the rest of the project;
  • RFC [4];
  • whenever you feel it will help presenting your work, your choices, the review process, etc.

11.5.2. Patch revision changelog

When improvements are requested, the new revision of each commit should include a changelog of the modifications between each submission. Note that when your patch series is introduced by a cover letter, an overall changelog may be added to the cover letter in addition to the changelog in the individual commits. The best thing to rework a patch series is by interactive rebasing: git rebase -i origin/master. Consult the git manual for more information.

When added to the individual commits, this changelog is added when editing the commit message. Below the Signed-off-by section, add --- and your changelog.

Although the changelog will be visible for the reviewers in the mail thread, as well as in patchwork, git will automatically ignores lines below --- when the patch will be merged. This is the intended behavior: the changelog is not meant to be preserved forever in the git history of the project.

Hereafter the recommended layout:

Patch title: short explanation, max 72 chars

A paragraph that explains the problem, and how it manifests itself. If
the problem is complex, it is OK to add more paragraphs. All paragraphs
should be wrapped at 72 characters.

A paragraph that explains the root cause of the problem. Again, more
than on paragraph is OK.

Finally, one or more paragraphs that explain how the problem is solved.
Don't hesitate to explain complex solutions in detail.

Signed-off-by: John DOE <john.doe@example.net>

---
Changes v2 -> v3:
  - foo bar  (suggested by Jane)
  - bar buz

Changes v1 -> v2:
  - alpha bravo  (suggested by John)
  - charly delta

Any patch revision should include the version number. The version number is simply composed of the letter v followed by an integer greater or equal to two (i.e. "PATCH v2", "PATCH v3" …).

This can be easily handled with git format-patch by using the option --subject-prefix:

$ git format-patch --subject-prefix "PATCH v4" \
    -M -o outgoing origin/master

11.6. Reporting issues/bugs or getting help

Before reporting any issue, please check the mailing list archive Section 10.1.1, “Subscribing to the mailing list” in case someone has already reported and fixed a similar problem.

However you choose to report bugs or get help, either by opening a bug Section 10.4, “Bugtracker” or by sending a mail to the mailing list Section 10.1.1, “Subscribing to the mailing list”, there are a number of details to provide in order to help people reproduce and find a solution to the issue.

Try to think as if you were trying to help someone else; in that case, what would you need?

Here is a short list of details to provide in such case:

  • host machine (OS/release)
  • version of Buildroot
  • target for which the build fails
  • package(s) for which the build fails
  • the command that fails and its output
  • any information you think that may be relevant

Additionally, you should add the .config file (or if you know how, a defconfig; see the section called “Buildroot configuration”).

If some of these details are too large, do not hesitate to use a pastebin service. Note that not all available pastebin services will preserve Unix-style line terminators when downloading raw pastes. Following pastebin services are known to work correctly: - https://gist.github.com/ - http://code.bulix.org/



[4] RFC: (Request for comments) change proposal

Chapter 12. Appendix

12.1. Makedev syntax documentation

The makedev syntax is used in several places in Buildroot to define changes to be made for permissions, or which device files to create and how to create them, in order to avoid calls to mknod.

This syntax is derived from the makedev utility, and more complete documentation can be found in the package/makedevs/README file.

It takes the form of a line for each file, with the following layout:

name

type

mode

uid

gid

major

minor

start

inc

count

There are a few non-trivial blocks here:

  • name is the path to the file you want to create/modify
  • type is the type of the file, being one of:

    • f: a regular file
    • d: a directory
    • c: a character device file
    • b: a block device file
    • p: a named pipe
  • mode, uid and gid are the usual permissions settings
  • major and minor are here for device files - set to - for other files
  • start, inc and count are for when you want to create a batch of files, and can be reduced to a loop, beginning at start, incrementing its counter by inc until it reaches count

Let’s say you want to change the permissions of a given file; using this syntax, you will need to put:

/usr/bin/foobar f       644     0       0       -       -       -       -       -

On the other hand, if you want to create the device file /dev/hda and the corresponding 15 files for the partitions, you will need for /dev/hda:

/dev/hda        b       640     0       0       3       0       0       0       -

and then for device files corresponding to the partitions of /dev/hda, /dev/hdaX, X ranging from 1 to 15:

/dev/hda        b       640     0       0       3       1       1       1       15

12.2. Makeuser syntax documentation

The syntax to create users is inspired by the makedev syntax, above, but is specific to Buildroot.

The syntax for adding a user is a space-separated list of fields, one user per line; the fields are:

username

uid

group

gid

password

home

shell

groups

comment

Where:

  • username is the desired user name (aka login name) for the user. It can not be root, and must be unique.
  • uid is the desired UID for the user. It must be unique, and not 0. If set to -1, then a unique UID will be computed by Buildroot in the range [1000…1999]
  • group is the desired name for the user’s main group. It can not be root. If the group does not exist, it will be created.
  • gid is the desired GID for the user’s main group. It must be unique, and not 0. If set to -1, and the group does not already exist, then a unique GID will be computed by Buildroot in the range [1000..1999]
  • password is the crypt(3)-encoded password. If prefixed with !, then login is disabled. If prefixed with =, then it is interpreted as clear-text, and will be crypt-encoded (using MD5). If prefixed with !=, then the password will be crypt-encoded (using MD5) and login will be disabled. If set to *, then login is not allowed.
  • home is the desired home directory for the user. If set to -, no home directory will be created, and the user’s home will be /. Explicitly setting home to / is not allowed.
  • shell is the desired shell for the user. If set to -, then /bin/false is set as the user’s shell.
  • groups is the comma-separated list of additional groups the user should be part of. If set to -, then the user will be a member of no additional group. Missing groups will be created with an arbitrary gid.
  • comment (aka GECOS field) is an almost-free-form text.

There are a few restrictions on the content of each field:

  • except for comment, all fields are mandatory.
  • except for comment, fields may not contain spaces.
  • no field may contain a colon (:).

If home is not -, then the home directory, and all files below, will belong to the user and its main group.

Examples:

foo -1 bar -1 !=blabla /home/foo /bin/sh alpha,bravo Foo user

This will create this user:

  • username (aka login name) is: foo
  • uid is computed by Buildroot
  • main group is: bar
  • main group gid is computed by Buildroot
  • clear-text password is: blabla, will be crypt(3)-encoded, and login is disabled.
  • home is: /home/foo
  • shell is: /bin/sh
  • foo is also a member of groups: alpha and bravo
  • comment is: Foo user
test 8000 wheel -1 = - /bin/sh - Test user

This will create this user:

  • username (aka login name) is: test
  • uid is : 8000
  • main group is: wheel
  • main group gid is computed by Buildroot, and will use the value defined in the rootfs skeleton
  • password is empty (aka no password).
  • home is / but will not belong to test
  • shell is: /bin/sh
  • test is not a member of any additional groups
  • comment is: Test user

12.3. List of target packages available in Buildroot

Packages Target packages → …

a10disp

→ Hardware handling

acl

→ System tools

acpid

→ Hardware handling

aespipe

→ Miscellaneous

agent++

→ Libraries → Networking

aiccu

→ Networking applications

aircrack-ng

→ Networking applications

alsa-lib

→ Libraries → Audio/Sound

alsa-utils

→ Audio and video applications

alsamixergui

→ Graphic libraries and applications (graphic/text)

am33x-cm3

→ Hardware handling → Firmware

apitrace

→ Graphic libraries and applications (graphic/text)

applewmproto

→ Graphic libraries and applications (graphic/text) → X11R7 X protocols

appres

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

apr

→ Libraries → Other

apr-util

→ Libraries → Other

argp-standalone

→ Libraries → Other

argus

→ Networking applications

armadillo

→ Libraries → Other

arptables

→ Networking applications

at

→ Shell and utilities

atftp

→ Networking applications

atk

→ Libraries → Graphics

attr

→ System tools

audiofile

→ Libraries → Audio/Sound

aumix

→ Audio and video applications

autossh

→ Networking applications

avahi

→ Networking applications

avrdude

→ Hardware handling

axel

→ Networking applications

b43-firmware

→ Hardware handling → Firmware

bash

→ Shell and utilities

bc

→ Miscellaneous

bcusdk

→ Networking applications

bdftopcf

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

beecrypt

→ Libraries → Crypto

beforelight

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

bellagio

→ Audio and video applications

berkeleydb

→ Libraries → Database

bigreqsproto

→ Graphic libraries and applications (graphic/text) → X11R7 X protocols

bind

→ Networking applications

binutils

→ Development tools

bison (deprecated)

→ Development tools

bitmap

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

blackbox (deprecated)

→ Graphic libraries and applications (graphic/text)

bluez-utils

→ Networking applications

bmon

→ Networking applications

boa

→ Networking applications

bonnie++

→ Debugging, profiling and benchmark

boost

→ Libraries → Other

bootutils

→ System tools

bridge-utils

→ Networking applications

bsdiff

→ Development tools

btrfs-progs

→ Filesystem and flash utilities

bustle

→ Development tools

BusyBox

bwm-ng

→ Networking applications

bzip2

→ Compressors and decompressors

c-ares

→ Libraries → Networking

CA Certificates

→ Libraries → Crypto

cache-calibrator

→ Debugging, profiling and benchmark

cairo

→ Libraries → Graphics

can-utils

→ Networking applications

cblas/clapack

→ Libraries → Other

ccid

→ Libraries → Hardware handling

ccrypt

→ Shell and utilities

cdrkit

→ Hardware handling

cegui06

→ Graphic libraries and applications (graphic/text)

cgilua

→ Interpreter languages and scripting → Lua libraries/modules

chrony

→ Networking applications

cifs-utils

→ Filesystem and flash utilities

civetweb

→ Networking applications

cJSON

→ Libraries → JSON/XML

classpath

→ Libraries → Other

collectd

→ Miscellaneous

compositeproto

→ Graphic libraries and applications (graphic/text) → X11R7 X protocols

connman

→ Networking applications

conntrack-tools

→ Networking applications

copas

→ Interpreter languages and scripting → Lua libraries/modules

coreutils

→ System tools

cosmo

→ Interpreter languages and scripting → Lua libraries/modules

coxpcall

→ Interpreter languages and scripting → Lua libraries/modules

cppcms

→ Libraries → Other

cppdb

→ Libraries → Database

cppzmq

→ Libraries → Networking

cpuload

→ System tools

cramfs

→ Filesystem and flash utilities

crda

→ Networking applications

cryptodev-linux

→ Libraries → Crypto → cryptodev variant

cryptsetup

→ Hardware handling

ctorrent

→ Networking applications

cups

→ Networking applications

curlftpfs (FUSE)

→ Filesystem and flash utilities

cvs

→ Development tools

cwiid

→ Hardware handling

czmq

→ Libraries → Networking

dado

→ Interpreter languages and scripting → Lua libraries/modules

damageproto

→ Graphic libraries and applications (graphic/text) → X11R7 X protocols

dash

→ Shell and utilities

dbus

→ Hardware handling

dbus-c++

→ Hardware handling

dbus-glib

→ Hardware handling

dbus-python

→ Hardware handling

dbus-triggerd

→ Hardware handling

dcron

→ System tools

Declarative module

→ Graphic libraries and applications (graphic/text)

DejaVu fonts

→ Graphic libraries and applications (graphic/text)

devmem2

→ Hardware handling

dhcp (ISC)

→ Networking applications

dhcpcd

→ Networking applications

dhcpdump

→ Networking applications

dhrystone

→ Debugging, profiling and benchmark

dialog

→ Shell and utilities

diffutils

→ Development tools

dillo

→ Graphic libraries and applications (graphic/text)

directfb

→ Graphic libraries and applications (graphic/text)

directfb examples

→ Graphic libraries and applications (graphic/text)

directfb virtual input extension

→ Graphic libraries and applications (graphic/text)

distcc (deprecated)

→ Development tools

dmalloc

→ Debugging, profiling and benchmark

dmidecode

→ Hardware handling

dmraid

→ Hardware handling

dmxproto

→ Graphic libraries and applications (graphic/text) → X11R7 X protocols

dnsmasq

→ Networking applications

docker

→ Graphic libraries and applications (graphic/text)

dosfstools

→ Filesystem and flash utilities

dri2proto

→ Graphic libraries and applications (graphic/text) → X11R7 X protocols

dri3proto

→ Graphic libraries and applications (graphic/text) → X11R7 X protocols

dropbear

→ Networking applications

dropwatch

→ Debugging, profiling and benchmark

dsp-tools

→ System tools

dstat

→ Debugging, profiling and benchmark

dtach

→ Shell and utilities

dtc (libfdt)

→ Libraries → Hardware handling

dtv-scan-tables

→ Hardware handling

duma

→ Debugging, profiling and benchmark

dvb-apps

→ Hardware handling

dvbsnoop

→ Hardware handling

e2fsprogs

→ Filesystem and flash utilities

e2tools

→ Filesystem and flash utilities

ebtables

→ Networking applications

ecryptfs-utils

→ Filesystem and flash utilities

ed

→ Text editors and viewers

editres

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

eeprog

→ Hardware handling

eigen

→ Libraries → Other

elfutils

→ Libraries → Other

empty

→ Miscellaneous

enchant

→ Libraries → Text and terminal handling

encodings

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

enlightenment

→ Graphic libraries and applications (graphic/text)

Enlightenment Foundation Libraries

→ Graphic libraries and applications (graphic/text)

enscript

→ Interpreter languages and scripting

erlang

→ Interpreter languages and scripting

ethtool

→ Networking applications

eudev

→ Hardware handling

evemu

→ Hardware handling

evtest

→ Hardware handling

exFAT (FUSE)

→ Filesystem and flash utilities

exfat-utils

→ Filesystem and flash utilities

exim

→ Mail

expat

→ Libraries → JSON/XML

expect

→ Interpreter languages and scripting → tcl libraries/modules

expedite

→ Graphic libraries and applications (graphic/text)

explorercanvas

→ Libraries → Javascript

ezxml

→ Libraries → JSON/XML

f2fs-tools

→ Filesystem and flash utilities

faad2

→ Audio and video applications

faifa

→ Networking applications

fan-ctrl

→ Hardware handling

fb-test-app

→ Graphic libraries and applications (graphic/text)

fbdump (Framebuffer Capture Tool)

→ Graphic libraries and applications (graphic/text)

fbgrab

→ Graphic libraries and applications (graphic/text)

fbset

→ Graphic libraries and applications (graphic/text)

fbterm

→ Graphic libraries and applications (graphic/text)

fbv

→ Graphic libraries and applications (graphic/text)

fconfig

→ Hardware handling

fdk-aac

→ Libraries → Audio/Sound

feh

→ Graphic libraries and applications (graphic/text)

fetchmail

→ Mail

ffmpeg

→ Audio and video applications

fftw

→ Libraries → Other

file

→ Shell and utilities

filemq

→ Libraries → Networking

findutils

→ Development tools

fio

→ Debugging, profiling and benchmark

firmware-imx

→ Hardware handling

fis

→ Hardware handling

fixesproto

→ Graphic libraries and applications (graphic/text) → X11R7 X protocols

flac

→ Audio and video applications

flann

→ Libraries → Other

flashbench

→ Filesystem and flash utilities

flashrom

→ Hardware handling

flex

→ Development tools

flite

→ Audio and video applications

flot

→ Libraries → Javascript

fltk

→ Libraries → Graphics

fluxbox

→ Graphic libraries and applications (graphic/text)

fmc

→ Networking applications

fmlib

→ Libraries → Networking

fmtools

→ Hardware handling

font-adobe-100dpi

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-adobe-75dpi

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-adobe-utopia-100dpi

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-adobe-utopia-75dpi

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-adobe-utopia-type1

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-alias

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-arabic-misc

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-bh-100dpi

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-bh-75dpi

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-bh-lucidatypewriter-100dpi

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-bh-lucidatypewriter-75dpi

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-bh-ttf

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-bh-type1

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-bitstream-100dpi

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-bitstream-75dpi

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-bitstream-type1

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-cronyx-cyrillic

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-cursor-misc

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-daewoo-misc

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-dec-misc

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-ibm-type1

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-isas-misc

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-jis-misc

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-micro-misc

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-misc-cyrillic

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-misc-ethiopic

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-misc-meltho

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-misc-misc

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-mutt-misc

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-schumacher-misc

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-screen-cyrillic

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-sony-misc

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-sun-misc

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-util

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-winitzki-cyrillic

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

font-xfree86-type1

→ Graphic libraries and applications (graphic/text) → X11R7 Fonts

fontcacheproto

→ Graphic libraries and applications (graphic/text) → X11R7 X protocols

fontconfig

→ Libraries → Graphics

fontsproto

→ Graphic libraries and applications (graphic/text) → X11R7 X protocols

fonttosfnt

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

foomatic_filters

→ Networking applications

fping

→ Networking applications

freerdp

→ Graphic libraries and applications (graphic/text)

Freescale i.MX libraries

→ Hardware handling

freetype

→ Libraries → Graphics

fslsfonts

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

fstobdf

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

fswebcam

→ Graphic libraries and applications (graphic/text)

ftop

→ System tools

fxload

→ Hardware handling

gadgetfs-test

→ Hardware handling

gamin

→ Libraries → Filesystem

gawk

→ Development tools

gd

→ Libraries → Graphics

gdb

→ Debugging, profiling and benchmark

gdbm

→ Libraries → Database

gdk-pixbuf

→ Libraries → Graphics

genext2fs

→ Filesystem and flash utilities

genromfs

→ Filesystem and flash utilities

geoip

→ Libraries → Networking

gesftpserver

→ Networking applications

gettext

→ Development tools

giblib

→ Libraries → Graphics

git

→ Development tools

glib-networking

→ Libraries → Networking

glibmm

→ Libraries → Other

glproto

→ Graphic libraries and applications (graphic/text) → X11R7 X protocols

gmp

→ Libraries → Other

gmpc

→ Graphic libraries and applications (graphic/text)

gnu-efi

→ Libraries → Hardware handling

gnuchess

→ Games

gnupg

→ Shell and utilities

gnupg2

→ Shell and utilities

gnuplot

→ Graphic libraries and applications (graphic/text)

gnutls

→ Libraries → Crypto

gob2 (deprecated)

→ Graphic libraries and applications (graphic/text)

Google font directory

→ Miscellaneous

google-breakpad

→ Debugging, profiling and benchmark

gperf

→ Development tools

gpm

→ Hardware handling

gpsd

→ Hardware handling

gptfdisk

→ Hardware handling

gpu-viv-bin-mx6q

→ Hardware handling

gqview

→ Graphic libraries and applications (graphic/text)

grantlee

→ Graphic libraries and applications (graphic/text)

grep

→ Development tools

gsl

→ Libraries → Other

gst-dsp

→ Audio and video applications

gst-ffmpeg

→ Audio and video applications

gst-fsl-plugins

→ Audio and video applications

gst-omapfb

→ Audio and video applications

gst-omx

→ Audio and video applications

gst-plugin-x170

→ Audio and video applications

gst-plugins-bad

→ Audio and video applications

gst-plugins-base

→ Audio and video applications

gst-plugins-good

→ Audio and video applications

gst-plugins-ugly

→ Audio and video applications

gst1-libav

→ Audio and video applications

gst1-plugins-bad

→ Audio and video applications

gst1-plugins-base

→ Audio and video applications

gst1-plugins-good

→ Audio and video applications

gst1-plugins-ugly

→ Audio and video applications

gstreamer 0.10

→ Audio and video applications

gstreamer 1.x

→ Audio and video applications

gtest

→ Libraries → Other

gtk engines

→ Libraries → Graphics

gtkperf (performance test for GTK2)

→ Graphic libraries and applications (graphic/text)

gutenprint

→ Networking applications

gvfs

→ Hardware handling

gzip

→ Compressors and decompressors

harfbuzz

→ Libraries → Graphics

haserl

→ Interpreter languages and scripting

haveged

→ Miscellaneous

hdparm

→ Hardware handling

heirloom-mailx

→ Mail

hiawatha

→ Networking applications

hicolor (default theme)

→ Libraries → Graphics → GTK Themes

hostapd

→ Networking applications

hplip

→ Networking applications

htop

→ System tools

httping

→ Networking applications

hwdata

→ Hardware handling

i2c-tools

→ Hardware handling

iceauth

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

ico

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

icu

→ Libraries → Text and terminal handling

ifplugd

→ Networking applications

iftop

→ Networking applications

igh-ethercat

→ Networking applications

igmpproxy

→ Networking applications

imagemagick

→ Graphic libraries and applications (graphic/text)

imlib2

→ Libraries → Graphics

imx-lib

→ Hardware handling

imx-vpu

→ Hardware handling

inadyn

→ Networking applications

infozip

→ Compressors and decompressors

inotify-tools

→ Shell and utilities

input-event-daemon

→ Hardware handling

input-tools

→ Hardware handling

inputproto

→ Graphic libraries and applications (graphic/text) → X11R7 X protocols

intel-microcode

→ Hardware handling

intltool

→ Development tools

iostat

→ Hardware handling

iozone

→ Debugging, profiling and benchmark

iperf

→ Networking applications

ipkg

→ Package managers

iproute2

→ Networking applications

iprutils

→ System tools

ipsec-tools

→ Networking applications

ipset

→ Networking applications

iptables

→ Networking applications

iptraf-ng

→ Networking applications

iputils

→ Networking applications

irda-utils

→ Hardware handling

iucode-tool

→ Hardware handling

iw

→ Networking applications

jack2

→ Audio and video applications

jamvm

→ Interpreter languages and scripting

jansson

→ Libraries → JSON/XML

jasper

→ Libraries → Graphics

jhead

→ Graphic libraries and applications (graphic/text)

jimtcl

→ Interpreter languages and scripting

joe

→ Text editors and viewers

jpeg

→ Libraries → Graphics → jpeg variant

jpeg-turbo

→ Libraries → Graphics → jpeg variant

jq

→ Development tools

jQuery

→ Libraries → Javascript

jQuery keyboard

→ Libraries → Javascript

jQuery UI

→ Libraries → Javascript

jQuery UI themes

→ Libraries → Javascript

jquery-mobile

→ Libraries → Javascript

jQuery-Sparkline

→ Libraries → Javascript

jQuery-Validation

→ Libraries → Javascript

jsmin

→ Libraries → Javascript

json-c

→ Libraries → JSON/XML

json-glib

→ Libraries → JSON/XML

json-javascript

→ Libraries → Javascript

kbd

→ Hardware handling

kbproto

→ Graphic libraries and applications (graphic/text) → X11R7 X protocols

kexec

→ Debugging, profiling and benchmark

kexec-lite

→ Debugging, profiling and benchmark

keyutils

→ System tools

kismet

→ Networking applications

kmod

→ System tools

knock

→ Networking applications

kobs-ng

→ Filesystem and flash utilities

ktap

→ Debugging, profiling and benchmark

lame

→ Audio and video applications

latencytop

→ Debugging, profiling and benchmark

lbase64

→ Interpreter languages and scripting → Lua libraries/modules

LBreakout2

→ Games

lcdapi

→ Libraries → Hardware handling

lcdproc

→ Hardware handling

lcms2

→ Libraries → Graphics

leafpad

→ Graphic libraries and applications (graphic/text)

less

→ Text editors and viewers

lesstif

→ Libraries → Graphics

lftp

→ Networking applications

libaio

→ Libraries → Hardware handling

libao

→ Libraries → Audio/Sound

libarchive

→ Libraries → Compression and decompression

libargtable2

→ Libraries → Other

libart

→ Libraries → Graphics

libass

→ Libraries → Multimedia

libassuan

→ Libraries → Crypto

libatasmart

→ Libraries → Hardware handling

libatomic_ops

→ Libraries → Other

libbluray

→ Libraries → Multimedia

libbsd

→ Libraries → Other

libcap

→ Libraries → Other

libcap-ng

→ Libraries → Other

libcdaudio

→ Libraries → Audio/Sound

libcdio

→ Libraries → Audio/Sound

libcec

→ Libraries → Hardware handling

libcgi

→ Libraries → Networking

libcgicc

→ Libraries → Networking

libcgroup

→ Libraries → Other

libcofi

→ Libraries → Other

libconfig

→ Libraries → Filesystem

libconfuse

→ Libraries → Filesystem

libcue

→ Libraries → Audio/Sound

libcuefile

→ Libraries → Audio/Sound

libcurl

→ Libraries → Networking

libdaemon

→ Libraries → Other

libdmtx

→ Libraries → Graphics

libdmx

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

libdnet

→ Libraries → Networking

libdrm

→ Libraries → Graphics

libdvbsi

→ Libraries → Multimedia

libdvdnav

→ Libraries → Multimedia

libdvdread

→ Libraries → Multimedia

libebml

→ Libraries → Multimedia

libecore

→ Graphic libraries and applications (graphic/text)

libedbus

→ Graphic libraries and applications (graphic/text)

libedit

→ Libraries → Text and terminal handling

libedje

→ Graphic libraries and applications (graphic/text)

libee

→ Libraries → Other

libeet

→ Graphic libraries and applications (graphic/text)

libefreet

→ Graphic libraries and applications (graphic/text)

libeina

→ Graphic libraries and applications (graphic/text)

libeio

→ Graphic libraries and applications (graphic/text)

libelementary

→ Graphic libraries and applications (graphic/text)

libelf

→ Libraries → Other

libembryo

→ Graphic libraries and applications (graphic/text)

libenca

→ Libraries → Text and terminal handling

Liberation (Free fonts)

→ Graphic libraries and applications (graphic/text)

libesmtp

→ Mail

libestr

→ Libraries → Text and terminal handling

libethumb

→ Graphic libraries and applications (graphic/text)

libev

→ Libraries → Other

libevas

→ Graphic libraries and applications (graphic/text)

libevas generic loaders

→ Graphic libraries and applications (graphic/text)

libevdev

→ Libraries → Other

libevent

→ Libraries → Other

libexif

→ Libraries → Graphics

libeXosip2

→ Libraries → Networking

libfcgi

→ Libraries → Networking

libffi

→ Libraries → Other

libfontenc

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

libfreefare

→ Libraries → Hardware handling

libfribidi

→ Libraries → Text and terminal handling

libFS

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

libfslcodec

→ Libraries → Multimedia

libfslparser

→ Libraries → Multimedia

libfslvpuwrap

→ Libraries → Multimedia

libftdi

→ Libraries → Hardware handling

libfuse

→ Libraries → Filesystem

libgail

→ Libraries → Graphics

libgc

→ Libraries → Other

libgcrypt

→ Libraries → Crypto

libgeotiff

→ Libraries → Graphics

libglade

→ Libraries → Graphics

libglew

→ Libraries → Graphics

libglib2

→ Libraries → Other

libglu

→ Libraries → Graphics

libgpg-error

→ Libraries → Crypto

libgpgme

→ Libraries → Crypto

libgsasl

→ Libraries → Networking

libgtk2

→ Libraries → Graphics

libhid

→ Libraries → Hardware handling

libical

→ Libraries → Other

libICE

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

libiconv

→ Libraries → Text and terminal handling

libid3tag

→ Libraries → Audio/Sound

libidn

→ Libraries → Networking

libinput

→ Libraries → Hardware handling

libiqrf

→ Libraries → Hardware handling

libiscsi

→ Libraries → Networking

libjson

→ Libraries → JSON/XML

libksba

→ Libraries → Crypto

libllcp

→ Libraries → Hardware handling

liblo

→ Libraries → Audio/Sound

liblockfile

→ Libraries → Filesystem

liblog4c-localtime

→ Libraries → Logging

liblogging

→ Libraries → Logging

libmad

→ Libraries → Audio/Sound

libmatroska

→ Libraries → Multimedia

libmbim

→ Libraries → Hardware handling

libmbus

→ Libraries → Networking

libmcrypt

→ Libraries → Crypto

libmemcached

→ Libraries → Networking

libmhash

→ Libraries → Crypto

libmicrohttpd

→ Libraries → Networking

libmms

→ Libraries → Multimedia

libmnl

→ Libraries → Networking

libmodbus

→ Libraries → Networking

libmodplug

→ Libraries → Audio/Sound

libmpd

→ Libraries → Audio/Sound

libmpdclient

→ Libraries → Audio/Sound

libmpeg2

→ Libraries → Multimedia

libndp

→ Libraries → Networking

libneon

→ Libraries → Networking

libnetfilter_acct

→ Libraries → Networking

libnetfilter_conntrack

→ Libraries → Networking

libnetfilter_cthelper

→ Libraries → Networking

libnetfilter_cttimeout

→ Libraries → Networking

libnetfilter_log

→ Libraries → Networking

libnetfilter_queue

→ Libraries → Networking

libnfc

→ Libraries → Hardware handling

libnfnetlink

→ Libraries → Networking

libnfs

→ Libraries → Filesystem

libnftnl

→ Libraries → Networking

libnl

→ Libraries → Networking

libnspr

→ Libraries → Other

libnss

→ Libraries → Crypto

liboauth

→ Libraries → Networking

libogg

→ Libraries → Multimedia

liboping

→ Libraries → Networking

libosip2

→ Libraries → Networking

libpcap

→ Libraries → Networking

libpciaccess

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

libpfm4

→ Libraries → Other

libplayer

→ Libraries → Multimedia

libplist

→ Libraries → Other

libpng

→ Libraries → Graphics

libpthread-stubs

→ Libraries → Other

libpthsem

→ Libraries → Other

libqmi

→ Libraries → Hardware handling

libqrencode

→ Libraries → Graphics

libraw

→ Libraries → Graphics

libraw1394

→ Libraries → Hardware handling

libreplaygain

→ Libraries → Audio/Sound

librsvg

→ Libraries → Graphics

librsync

→ Libraries → Networking

librtlsdr

→ Libraries → Hardware handling

librtmp

→ Libraries → Networking

libsamplerate

→ Libraries → Audio/Sound

libseccomp

→ Libraries → Other

libsecret

→ Libraries → Crypto

libsepol

→ Libraries → Security

libserial

→ Libraries → Hardware handling

libsexy

→ Graphic libraries and applications (graphic/text)

libsha1

→ Libraries → Crypto

libshairplay

→ Libraries → Networking

libsigc++

→ Libraries → Other

libsigsegv

→ Libraries → Other

libSM

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

libsndfile

→ Libraries → Audio/Sound

libsoc

→ Libraries → Hardware handling

libsocketcan

→ Libraries → Networking

libsoup

→ Libraries → Networking

libsoxr

→ Libraries → Audio/Sound

libssh2

→ Libraries → Crypto

libstrophe

→ Libraries → Networking

libsvg

→ Libraries → Graphics

libsvg-cairo

→ Libraries → Graphics

libsvgtiny

→ Libraries → Graphics

libsysfs

→ Libraries → Filesystem

libtasn1

→ Libraries → Other

libtheora

→ Libraries → Multimedia

libtirpc

→ Libraries → Networking

libtool

→ Development tools

libtorrent

→ Libraries → Networking

libtpl

→ Libraries → Other

libubox

→ Libraries → Other

libuci

→ Libraries → Other

libungif

→ Libraries → Graphics

libunwind

→ Libraries → Other

libupnp

→ Libraries → Networking

liburcu

→ Libraries → Other

libusb

→ Libraries → Hardware handling

libusb-compat

→ Libraries → Hardware handling

libuv

→ Libraries → Other

libv4l

→ Libraries → Hardware handling

libva

→ Libraries → Graphics

libva-intel-driver

→ Libraries → Graphics

libvncserver

→ Libraries → Networking

libvorbis

→ Libraries → Audio/Sound

libvpx

→ Audio and video applications

libwebsockets

→ Libraries → Networking

libX11

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

libXau

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

libXaw

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

libxcb

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

libXcomposite

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

libXcursor

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

libXdamage

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

libXdmcp

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

libXext

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

libXfixes

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

libXfont

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

libXft

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

libXi

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

libXinerama

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

libxkbcommon

→ Libraries → Hardware handling

libxkbfile

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

libxml++

→ Libraries → JSON/XML

libxml2

→ Libraries → JSON/XML

libxmlrpc

→ Libraries → JSON/XML

libXmu

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

libXpm

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

libXrandr

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

libXrender

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

libXres

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

libXScrnSaver

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

libxshmfence

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

libxslt

→ Libraries → JSON/XML

libXt

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

libXtst

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

libXv

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

libXvMC

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

libXxf86dga

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

libXxf86vm

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

libyaml

→ Libraries → JSON/XML

lighttpd

→ Networking applications

linenoise

→ Libraries → Text and terminal handling

linknx

→ Networking applications

links

→ Networking applications

linphone

→ Networking applications

linux-firmware

→ Hardware handling → Firmware

linux-fusion communication layer for DirectFB multi

→ Graphic libraries and applications (graphic/text)

linux-pam

→ Libraries → Other

linux-zigbee

→ Networking applications

listres

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

LiTE (toolbox engine)

→ Graphic libraries and applications (graphic/text)

live555

→ Libraries → Multimedia

ljlinenoise

→ Interpreter languages and scripting → Lua libraries/modules

ljsyscall

→ Interpreter languages and scripting → Lua libraries/modules

lm-sensors

→ Hardware handling

lmbench

→ Debugging, profiling and benchmark

lockdev

→ Libraries → Filesystem

lockfile programs

→ Shell and utilities

log4cplus

→ Libraries → Logging

log4cxx

→ Libraries → Logging

logrotate

→ Shell and utilities

logsurfer

→ Shell and utilities

lpeg

→ Interpreter languages and scripting → Lua libraries/modules

lpty

→ Interpreter languages and scripting → Lua libraries/modules

lrandom

→ Interpreter languages and scripting → Lua libraries/modules

lrzsz

→ Networking applications

lshw

→ Hardware handling

lsof

→ Debugging, profiling and benchmark

lsqlite3

→ Interpreter languages and scripting → Lua libraries/modules

lsuio

→ Hardware handling

ltp-testsuite

→ Debugging, profiling and benchmark

ltrace

→ Debugging, profiling and benchmark

LTris

→ Games

lttng-babeltrace

→ Debugging, profiling and benchmark

lttng-libust

→ Libraries → Other

lttng-modules

→ Debugging, profiling and benchmark

lttng-tools

→ Debugging, profiling and benchmark

lua

→ Interpreter languages and scripting

lua-cjson

→ Interpreter languages and scripting → Lua libraries/modules

lua-coat

→ Interpreter languages and scripting → Lua libraries/modules

lua-coatpersistent

→ Interpreter languages and scripting → Lua libraries/modules

lua-csnappy

→ Interpreter languages and scripting → Lua libraries/modules

lua-ev

→ Interpreter languages and scripting → Lua libraries/modules

lua-messagepack

→ Interpreter languages and scripting → Lua libraries/modules

lua-msgpack-native

→ Interpreter languages and scripting → Lua libraries/modules

lua-testmore

→ Interpreter languages and scripting → Lua libraries/modules

luabitop

→ Interpreter languages and scripting → Lua libraries/modules

luacrypto

→ Interpreter languages and scripting → Lua libraries/modules

luaexpat

→ Interpreter languages and scripting → Lua libraries/modules

luaexpatutils

→ Interpreter languages and scripting → Lua libraries/modules

luafilesystem

→ Interpreter languages and scripting → Lua libraries/modules

luajit

→ Interpreter languages and scripting

luajson

→ Interpreter languages and scripting → Lua libraries/modules

lualogging

→ Interpreter languages and scripting → Lua libraries/modules

luaposix

→ Interpreter languages and scripting → Lua libraries/modules

luasec

→ Interpreter languages and scripting → Lua libraries/modules

luasocket

→ Interpreter languages and scripting → Lua libraries/modules

luasql-sqlite3

→ Interpreter languages and scripting → Lua libraries/modules

luit

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

lunit

→ Interpreter languages and scripting → Lua libraries/modules

lvm2 & device mapper

→ Hardware handling

lxc

→ System tools

lz4

→ Compressors and decompressors

lzip

→ Compressors and decompressors

lzlib

→ Interpreter languages and scripting → Lua libraries/modules

lzo

→ Libraries → Compression and decompression

lzop

→ Compressors and decompressors

m4 (deprecated)

→ Development tools

macchanger

→ Networking applications

madplay

→ Audio and video applications

make

→ Development tools

makedepend

→ Graphic libraries and applications (graphic/text) → X11R7 Utilities

makedevs

→ Filesystem and flash utilities

Matchbox Desktop

→ Graphic libraries and applications (graphic/text)

Matchbox Panel

→ Graphic libraries and applications (graphic/text)

Matchbox session common files

→ Graphic libraries and applications (graphic/text)

Matchbox Virtual Keyboard

→ Graphic libraries and applications (graphic/text)

MatchBox Window Manager

→ Graphic libraries and applications (graphic/text)

mcookie

→ Graphic libraries and applications (graphic/text) → X11R7 Utilities

mcrypt

→ Miscellaneous

mdadm

→ Hardware handling

media-ctl

→ Hardware handling

mediastreamer

→ Libraries → Multimedia

memcached

→ Networking applications

memstat

→ Debugging, profiling and benchmark

memtester

→ Hardware handling

mesa3d

→ Graphic libraries and applications (graphic/text)

metacity

→ Graphic libraries and applications (graphic/text)

midori

→ Graphic libraries and applications (graphic/text)

mii-diag

→ Networking applications

Mini-XML

→ Libraries → JSON/XML

minicom

→ Hardware handling

minidlna

→ Networking applications

mkfontdir

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

mkfontscale

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

mmc-utils

→ Filesystem and flash utilities

mobile-broadband-provider-info

→ Miscellaneous

modemmanager

→ Networking applications

mongoose

→ Networking applications

mongrel2

→ Networking applications

monit

→ System tools

mpc

→ Libraries → Other

mpd

→ Audio and video applications

mpfr

→ Libraries → Other

mpg123

→ Audio and video applications

mplayer

→ Audio and video applications

mrouted

→ Networking applications

msgpack

→ Libraries → Other

msmtp

→ Mail

mtd, jffs2 and ubi/ubifs tools

→ Filesystem and flash utilities

mtdev

→ Libraries → Hardware handling

mtdev2tuio

→ Libraries → Other

mtools

→ Filesystem and flash utilities

mtr

→ Networking applications

Multimedia Module

→ Graphic libraries and applications (graphic/text)

musepack

→ Audio and video applications

mutt

→ Mail

MySQL

→ Libraries → Database

nano

→ Text editors and viewers

nanocom

→ Hardware handling

nbd

→ Networking applications

ncdu

→ System tools

ncftp

→ Networking applications

ncmpc

→ Audio and video applications

ncurses

→ Libraries → Text and terminal handling

ndisc6 tools

→ Networking applications

ne10

→ Libraries → Hardware handling

neard

→ Hardware handling

neardal

→ Libraries → Hardware handling

net-tools

→ Networking applications

netatalk

→ Networking applications

netcat

→ Networking applications

netperf

→ Debugging, profiling and benchmark

netplug

→ Networking applications

netsnmp

→ Networking applications

netstat-nat

→ Networking applications

nettle

→ Libraries → Crypto

networkmanager

→ Networking applications

newt

→ Libraries → Text and terminal handling

nfacct

→ Networking applications

nfs-utils

→ Filesystem and flash utilities

nftables

→ Networking applications

ngircd

→ Networking applications

ngrep

→ Networking applications

nmap

→ Networking applications

nodejs

→ Interpreter languages and scripting

noip

→ Networking applications

nss-mdns

→ Libraries → Networking

ntfs-3g

→ Filesystem and flash utilities

ntp

→ Networking applications

numactl

→ System tools

nut

→ System tools

nuttcp

→ Networking applications

ocf-linux

→ Libraries → Crypto → cryptodev variant

oclock

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

ocrad

→ Graphic libraries and applications (graphic/text)

ofono

→ Hardware handling

ola (open lighting architecture)

→ Hardware handling

olsrd

→ Networking applications

omniorb

→ Libraries → Networking

on2-8170-libs

→ Audio and video applications

on2-8170-modules

→ Hardware handling

open2300

→ Hardware handling

opencore-amr

→ Libraries → Audio/Sound

opencv

→ Libraries → Graphics

openntpd

→ Networking applications

openobex

→ Networking applications

openocd

→ Hardware handling

openpgm

→ Libraries → Networking

openpowerlink

→ Hardware handling

openssh

→ Networking applications

openssl

→ Libraries → Crypto

openswan

→ Networking applications

OpenTyrian

→ Games

OpenTyrian data

→ Games

openvpn

→ Networking applications

opkg

→ Package managers

oprofile

→ Debugging, profiling and benchmark

opus

→ Libraries → Audio/Sound

opus-tools

→ Audio and video applications

orbit

→ Interpreter languages and scripting → Lua libraries/modules

orc

→ Libraries → Other

oRTP

→ Libraries → Networking

owl-linux

→ Hardware handling

p11-kit

→ Libraries → Other

p910nd

→ Networking applications

pango

→ Libraries → Graphics

parted

→ Hardware handling

patch

→ Development tools

pax-utils

→ Debugging, profiling and benchmark

pciutils

→ Hardware handling

pcmanfm

→ Graphic libraries and applications (graphic/text)

pcre

→ Libraries → Text and terminal handling

pcsc-lite

→ Libraries → Hardware handling

perf

→ Debugging, profiling and benchmark

perl

→ Interpreter languages and scripting

perl-datetime-tiny

→ Interpreter languages and scripting → Perl libraries/modules

perl-gd

→ Interpreter languages and scripting → Perl libraries/modules

perl-gdgraph

→ Interpreter languages and scripting → Perl libraries/modules

perl-gdtextutil

→ Interpreter languages and scripting → Perl libraries/modules

perl-io-socket-ssl

→ Interpreter languages and scripting → Perl libraries/modules

perl-json-tiny

→ Interpreter languages and scripting → Perl libraries/modules

perl-mojolicious

→ Interpreter languages and scripting → Perl libraries/modules

perl-net-ssleay

→ Interpreter languages and scripting → Perl libraries/modules

perl-path-tiny

→ Interpreter languages and scripting → Perl libraries/modules

perl-try-tiny

→ Interpreter languages and scripting → Perl libraries/modules

perl-xml-libxml

→ Interpreter languages and scripting → Perl libraries/modules

perl-xml-namespacesupport

→ Interpreter languages and scripting → Perl libraries/modules

perl-xml-sax

→ Interpreter languages and scripting → Perl libraries/modules

perl-xml-sax-base

→ Interpreter languages and scripting → Perl libraries/modules

php

→ Interpreter languages and scripting

php-geoip

→ Interpreter languages and scripting → External php extensions

php-gnupg

→ Interpreter languages and scripting → External php extensions

php-imagick

→ Interpreter languages and scripting → External php extensions

php-memcached

→ Interpreter languages and scripting → External php extensions

php-ssh2

→ Interpreter languages and scripting → External php extensions

php-yaml

→ Interpreter languages and scripting → External php extensions

php-zmq

→ Interpreter languages and scripting → External php extensions

picocom

→ Hardware handling

pifmrds

→ Hardware handling

pinentry

→ Shell and utilities

pixman

→ Libraries → Graphics

pkgconf

→ Development tools

poco

→ Libraries → Other

polarssl

→ Libraries → Crypto

polkit

→ System tools

poppler

→ Libraries → Graphics

popt

→ Libraries → Text and terminal handling

portaudio

→ Libraries → Audio/Sound

portmap

→ Networking applications

postgresql

→ Libraries → Database

powerpc-utils

→ System tools

pppd

→ Networking applications

pptp-linux

→ Networking applications

PrBoom

→ Games

presentproto

→ Graphic libraries and applications (graphic/text) → X11R7 X protocols

procps-ng

→ System tools

proftpd

→ Networking applications

protobuf

→ Libraries → Other

protobuf-c

→ Libraries → Other

proxychains-ng

→ Networking applications

psmisc

→ System tools

psplash

→ Graphic libraries and applications (graphic/text)

ptpd

→ Networking applications

ptpd2

→ Networking applications

pulseaudio

→ Audio and video applications

pv

→ Debugging, profiling and benchmark

pwgen

→ System tools

python

→ Interpreter languages and scripting

python-bottle

→ Interpreter languages and scripting → external python modules

python-configobj

→ Interpreter languages and scripting → external python modules

python-crc16

→ Interpreter languages and scripting → external python modules

python-dialog

→ Interpreter languages and scripting → external python modules

python-dpkt

→ Interpreter languages and scripting → external python modules

python-id3

→ Interpreter languages and scripting → external python modules

python-ipy

→ Interpreter languages and scripting → external python modules

python-json-schema-validator

→ Interpreter languages and scripting → external python modules

python-keyring

→ Interpreter languages and scripting → external python modules

python-libconfig

→ Interpreter languages and scripting → external python modules

python-mad

→ Interpreter languages and scripting → external python modules

python-meld3

→ Interpreter languages and scripting → external python modules

python-msgpack

→ Interpreter languages and scripting → external python modules

python-netifaces

→ Interpreter languages and scripting → external python modules

python-nfc

→ Interpreter languages and scripting → external python modules

python-numpy

→ Interpreter languages and scripting → external python modules

python-posix-ipc

→ Interpreter languages and scripting → external python modules

python-protobuf

→ Interpreter languages and scripting → external python modules

python-pyasn

→ Interpreter languages and scripting → external python modules

python-pycrypto

→ Interpreter languages and scripting → external python modules

python-pygame

→ Interpreter languages and scripting → external python modules

python-pyparsing

→ Interpreter languages and scripting → external python modules

python-pypcap

→ Interpreter languages and scripting → external python modules

python-pyro

→ Interpreter languages and scripting → external python modules

python-pysnmp

→ Interpreter languages and scripting → external python modules

python-pysnmp-apps

→ Interpreter languages and scripting → external python modules

python-pysnmp-mibs

→ Interpreter languages and scripting → external python modules

python-pyusb

→ Interpreter languages and scripting → external python modules

python-pyzmq

→ Interpreter languages and scripting → external python modules

python-serial

→ Interpreter languages and scripting → external python modules

python-setuptools

→ Interpreter languages and scripting → external python modules

python-simplejson

→ Interpreter languages and scripting → external python modules

python-thrift

→ Interpreter languages and scripting → external python modules

python-tornado

→ Interpreter languages and scripting → external python modules

python-versiontools

→ Interpreter languages and scripting → external python modules

python3

→ Interpreter languages and scripting

qdecoder

→ Libraries → Networking

qextserialport

→ Graphic libraries and applications (graphic/text)

qhull

→ Libraries → Other

qjson

→ Graphic libraries and applications (graphic/text)

Qt

→ Graphic libraries and applications (graphic/text)

Qt5

→ Graphic libraries and applications (graphic/text)

qt5base

→ Graphic libraries and applications (graphic/text)

qt5connectivity

→ Graphic libraries and applications (graphic/text)

qt5declarative

→ Graphic libraries and applications (graphic/text)

qt5enginio

→ Graphic libraries and applications (graphic/text)

qt5graphicaleffects

→ Graphic libraries and applications (graphic/text)

qt5imageformats

→ Graphic libraries and applications (graphic/text)

qt5multimedia

→ Graphic libraries and applications (graphic/text)

qt5quick1

→ Graphic libraries and applications (graphic/text)

qt5quickcontrols

→ Graphic libraries and applications (graphic/text)

qt5script

→ Graphic libraries and applications (graphic/text)

qt5sensors

→ Graphic libraries and applications (graphic/text)

qt5serialport

→ Graphic libraries and applications (graphic/text)

qt5svg

→ Graphic libraries and applications (graphic/text)

qt5webkit

→ Graphic libraries and applications (graphic/text)

qt5webkit examples

→ Graphic libraries and applications (graphic/text)

qt5websockets

→ Graphic libraries and applications (graphic/text)

qt5x11extras

→ Graphic libraries and applications (graphic/text)

qt5xmlpatterns

→ Graphic libraries and applications (graphic/text)

qtuio

→ Graphic libraries and applications (graphic/text)

quagga

→ Networking applications

quota

→ System tools

qwt

→ Graphic libraries and applications (graphic/text)

radvd

→ Networking applications

ramspeed

→ Debugging, profiling and benchmark

ramspeed/smp

→ Debugging, profiling and benchmark

randrproto

→ Graphic libraries and applications (graphic/text) → X11R7 X protocols

rapidjson

→ Libraries → JSON/XML

rdesktop

→ Graphic libraries and applications (graphic/text)

read-edid

→ Hardware handling

readline

→ Libraries → Text and terminal handling

recordproto

→ Graphic libraries and applications (graphic/text) → X11R7 X protocols

redis

→ Libraries → Database

renderproto

→ Graphic libraries and applications (graphic/text) → X11R7 X protocols

resourceproto

→ Graphic libraries and applications (graphic/text) → X11R7 X protocols

rgb

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

rings

→ Interpreter languages and scripting → Lua libraries/modules

rng-tools

→ Hardware handling

roxml

→ Libraries → JSON/XML

rp-pppoe

→ Networking applications

rpcbind

→ Networking applications

rpi-firmware

→ Hardware handling → Firmware

rpi-userland

→ Hardware handling

rpm

→ Package managers

rrdtool

→ Graphic libraries and applications (graphic/text)

rsh-redone

→ Networking applications

rstart

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

rsync

→ Networking applications

rsyslog

→ System tools

rt-tests

→ Debugging, profiling and benchmark

rtai

→ Real-Time

rtorrent

→ Networking applications

rtptools

→ Networking applications

rubix

→ Games

ruby

→ Interpreter languages and scripting

samba

→ Networking applications

samba4

→ Networking applications

sane-backends

→ Hardware handling

SawMan (Window Manager)

→ Graphic libraries and applications (graphic/text)

schifra

→ Libraries → Other

sconeserver

→ Networking applications

screen

→ Shell and utilities

Script Module

→ Graphic libraries and applications (graphic/text)

scripts

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

scrnsaverproto

→ Graphic libraries and applications (graphic/text) → X11R7 X protocols

SDL

→ Graphic libraries and applications (graphic/text)

SDL_gfx

→ Graphic libraries and applications (graphic/text)

SDL_image

→ Graphic libraries and applications (graphic/text)

SDL_mixer

→ Graphic libraries and applications (graphic/text)

SDL_net

→ Graphic libraries and applications (graphic/text)

SDL_sound

→ Graphic libraries and applications (graphic/text)

SDL_TTF

→ Graphic libraries and applications (graphic/text)

sdparm

→ Hardware handling

sed

→ Development tools

ser2net

→ Networking applications

sessreg

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

setserial

→ Hardware handling

setxkbmap

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

sg3-utils

→ Hardware handling

shared-mime-info

→ Miscellaneous

shareware Doom WAD file

→ Games

showfont

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

simicsfs

→ Filesystem and flash utilities

sispmctl

→ Hardware handling

slang

→ Libraries → Text and terminal handling

slirp

→ Libraries → Networking

smack

→ System tools

smartmontools

→ Hardware handling

smcroute

→ Networking applications

smproxy

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

smstools3

→ Hardware handling

snappy

→ Libraries → Compression and decompression

snmp++

→ Libraries → Networking

snowball-hdmiservice

→ Hardware handling

snowball-init

→ Miscellaneous

socat

→ Networking applications

socketcand

→ Networking applications

sound-theme-borealis

→ Miscellaneous

sound-theme-freedesktop

→ Miscellaneous

sox

→ Audio and video applications

spawn-fcgi

→ Networking applications

speex

→ Libraries → Audio/Sound

spice protocol

→ Networking applications

spice server

→ Networking applications

sqlcipher

→ Libraries → Database

sqlite

→ Libraries → Database

squashfs

→ Filesystem and flash utilities

squid

→ Networking applications

sredird

→ Hardware handling

sshfs (FUSE)

→ Filesystem and flash utilities

sshpass

→ Networking applications

sstrip

→ Development tools

startup-notification

→ Libraries → Other

statserial

→ Hardware handling

strace

→ Debugging, profiling and benchmark

stress

→ Debugging, profiling and benchmark

strongswan

→ Networking applications

stunnel

→ Networking applications

subversion

→ Development tools

sudo

→ Shell and utilities

sunxi nand-part

→ Filesystem and flash utilities

sunxi script.bin board file

→ Hardware handling → Firmware

sunxi-cedarx

→ Hardware handling

sunxi-mali

→ Hardware handling

supervisor

→ System tools

SVG Module

→ Graphic libraries and applications (graphic/text)

sylpheed

→ Mail

synergy

→ Graphic libraries and applications (graphic/text)

syslogd & klogd

→ System tools

sysprof

→ Debugging, profiling and benchmark

sysstat

→ Hardware handling

systemd

→ System tools

sysvinit

→ System tools

taglib

→ Libraries → Audio/Sound

tar

→ Development tools

tcl

→ Interpreter languages and scripting

tclap

→ Libraries → Text and terminal handling

tcllib

→ Interpreter languages and scripting → tcl libraries/modules

tcpdump

→ Networking applications

tcping

→ Networking applications

tcpreplay

→ Networking applications

tftpd

→ Networking applications

thrift

→ Libraries → Networking

thttpd

→ Networking applications

ti-gfx

→ Hardware handling

ti-uim

→ Hardware handling

ti-utils

→ Hardware handling

tidsp-binaries

→ Audio and video applications

tiff

→ Libraries → Graphics

time

→ Shell and utilities

tinyhttpd

→ Networking applications

tinymembench

→ Debugging, profiling and benchmark

tinyxml

→ Libraries → JSON/XML

tmux

→ Shell and utilities

tn5250

→ Networking applications

torsmo

→ Graphic libraries and applications (graphic/text)

trace-cmd

→ Debugging, profiling and benchmark

transmission

→ Networking applications

tree

→ Development tools

tremor (fixed point vorbis decoder)

→ Libraries → Audio/Sound

tslib

→ Libraries → Hardware handling

tstools

→ Audio and video applications

tvheadend

→ Networking applications

twm

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

twolame

→ Audio and video applications

u-boot tools

→ Hardware handling

udisks

→ Hardware handling

udpcast

→ Networking applications

uemacs

→ Text editors and viewers

ulogd

→ Networking applications

unionfs (FUSE)

→ Filesystem and flash utilities

upmpdcli

→ Audio and video applications

urg

→ Libraries → Hardware handling

usb_modeswitch

→ Hardware handling

usb_modeswitch_data

→ Hardware handling

usbmount

→ Hardware handling

usbredir

→ Libraries → Networking

usbutils

→ Hardware handling

ushare

→ Networking applications

ussp-push

→ Networking applications

util-linux

→ System tools

util-macros

→ Graphic libraries and applications (graphic/text) → X11R7 Utilities

ux500-firmware

→ Hardware handling → Firmware

valgrind

→ Debugging, profiling and benchmark

vde2

→ Networking applications

videoproto

→ Graphic libraries and applications (graphic/text) → X11R7 X protocols

viewres

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

vim

→ Text editors and viewers

vlc

→ Audio and video applications

vo-aacenc

→ Libraries → Audio/Sound

vorbis-tools

→ Audio and video applications

vpnc

→ Networking applications

vsftpd

→ Networking applications

vtun

→ Networking applications

w_scan

→ Hardware handling

wavpack

→ Audio and video applications

wayland

→ Libraries → Graphics

webkit

→ Libraries → Graphics

WebKit Module

→ Graphic libraries and applications (graphic/text)

webp

→ Libraries → Graphics

webrtc-audio-processing

→ Libraries → Audio/Sound

weston

→ Graphic libraries and applications (graphic/text)

wget

→ Networking applications

whetstone

→ Debugging, profiling and benchmark

which

→ Shell and utilities

whois

→ Networking applications

windowswmproto

→ Graphic libraries and applications (graphic/text) → X11R7 X protocols

wipe

→ Hardware handling

wireless tools

→ Networking applications

wireless-regdb

→ Networking applications

wireshark

→ Networking applications

wmctrl

→ Graphic libraries and applications (graphic/text)

wpa_supplicant

→ Networking applications

wsapi

→ Interpreter languages and scripting → Lua libraries/modules

wvdial

→ Networking applications

wvstreams

→ Libraries → Networking

x11perf

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

x11vnc

→ Graphic libraries and applications (graphic/text)

xauth

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xavante

→ Interpreter languages and scripting → Lua libraries/modules

xbacklight

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xbiff

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xbitmaps

→ Graphic libraries and applications (graphic/text) → X11R7 Other data

xbmc

→ Audio and video applications

xbmc-addon-xvdr

→ Audio and video applications

xbmc-pvr-addons

→ Audio and video applications

xcalc

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xcb-proto

→ Graphic libraries and applications (graphic/text) → X11R7 X protocols

xcb-util

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

xcb-util-image

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

xcb-util-keysyms

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

xcb-util-wm

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

xclipboard

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xclock

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xcmiscproto

→ Graphic libraries and applications (graphic/text) → X11R7 X protocols

xcmsdb

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xconsole

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xcursor-transparent-theme

→ Graphic libraries and applications (graphic/text) → X11R7 Other data

xcursorgen

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xdata_xcursor-themes

→ Graphic libraries and applications (graphic/text) → X11R7 Other data

xdbedizzy

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xditview

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xdm

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xdpyinfo

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xdriinfo

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xedit

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

Xenomai Userspace

→ Real-Time

xerces-c++

→ Libraries → JSON/XML

xev

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xextproto

→ Graphic libraries and applications (graphic/text) → X11R7 X protocols

xeyes

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xf86-input-evdev

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-input-joystick

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-input-keyboard

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-input-mouse

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-input-synaptics

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-input-tslib

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-input-vmmouse

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-input-void

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-video-ark

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-video-ast

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-video-ati

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-video-cirrus

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-video-dummy

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-video-fbdev

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-video-geode

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-video-glide

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-video-glint

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-video-i128

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-video-intel

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-video-mach64

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-video-mga

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-video-neomagic

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-video-nv

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-video-openchrome

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-video-r128

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-video-savage

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-video-siliconmotion

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-video-sis

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-video-tdfx

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-video-tga

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-video-trident

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-video-v4l

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-video-vesa

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-video-vmware

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-video-voodoo

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86-video-wsfb

→ Graphic libraries and applications (graphic/text) → X11R7 Drivers

xf86bigfontproto

→ Graphic libraries and applications (graphic/text) → X11R7 X protocols

xf86dga

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xf86dgaproto

→ Graphic libraries and applications (graphic/text) → X11R7 X protocols

xf86driproto

→ Graphic libraries and applications (graphic/text) → X11R7 X protocols

xf86vidmodeproto

→ Graphic libraries and applications (graphic/text) → X11R7 X protocols

xfd

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xfontsel

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xfs

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xfsinfo

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xfsprogs

→ Filesystem and flash utilities

xgamma

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xgc

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xhost

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xineramaproto

→ Graphic libraries and applications (graphic/text) → X11R7 X protocols

xinetd

→ Networking applications

xinit

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xinput

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xinput-calibrator

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xkbcomp

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xkbevd

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xkbprint

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xkbutils

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xkeyboard-config

→ Graphic libraries and applications (graphic/text)

xkill

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xl2tp

→ Networking applications

xload

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xlogo

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xlsatoms

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xlsclients

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xlsfonts

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xmag

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xman

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xmessage

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xmh

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

XML Patterns Module

→ Graphic libraries and applications (graphic/text)

xmlstarlet

→ Shell and utilities

xmodmap

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xmore

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xorg-server

→ Graphic libraries and applications (graphic/text) → X11R7 Servers

xpr

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xprop

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xproto

→ Graphic libraries and applications (graphic/text) → X11R7 X protocols

xrandr

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xrdb

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xrefresh

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xscreensaver

→ Graphic libraries and applications (graphic/text)

xset

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xsetmode

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xsetpointer

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xsetroot

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xsm

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xstdcmap

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xterm

→ Graphic libraries and applications (graphic/text)

xtrans

→ Graphic libraries and applications (graphic/text) → X11R7 Libraries

xvidtune

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xvinfo

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xvkbd

→ Graphic libraries and applications (graphic/text)

xwd

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xwininfo

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xwud

→ Graphic libraries and applications (graphic/text) → X11R7 Applications

xz-utils

→ Compressors and decompressors

yajl

→ Libraries → JSON/XML

yasm

→ Development tools

yavta

→ Audio and video applications

zd1211-firmware

→ Hardware handling → Firmware

zeromq

→ Libraries → Networking

zlib

→ Libraries → Compression and decompression

zlog

→ Libraries → Logging

zmqpp

→ Libraries → Networking

znc

→ Networking applications

zsh

→ Shell and utilities

zxing

→ Libraries → Graphics

zyre

→ Libraries → Networking

12.4. List of virtual packages

These are the virtual packages known to Buildroot, with the corresponding symbols and providers.

Virtual packages Symbols Providers

cryptodev

BR2_PACKAGE_HAS_CRYPTODEV

cryptodev-linux, ocf-linux

jpeg

BR2_PACKAGE_HAS_JPEG

jpeg, jpeg-turbo

libegl

BR2_PACKAGE_HAS_LIBEGL

mesa3d (w/ OpenGL EGL), gpu-viv-bin-mx6q, rpi-userland, sunxi-mali, ti-gfx

libgl

BR2_PACKAGE_HAS_LIBGL

mesa3d (w/ DRI swrast driver), mesa3d (w/ DRI i965 driver), mesa3d (w/ DRI radeon driver)

libgles

BR2_PACKAGE_HAS_LIBGLES

mesa3d (w/ OpenGL ES), gpu-viv-bin-mx6q, rpi-userland, sunxi-mali, ti-gfx

libopenmax

BR2_PACKAGE_HAS_LIBOPENMAX

bellagio, rpi-userland

libopenvg

BR2_PACKAGE_HAS_LIBOPENVG

rpi-userland

luainterpreter

BR2_PACKAGE_HAS_LUAINTERPRETER

lua, luajit

powervr

BR2_PACKAGE_HAS_POWERVR

ti-gfx

udev

BR2_PACKAGE_HAS_UDEV

eudev, systemd

12.5. List of host utilities available in Buildroot

The following packages are all available in the menu Host utilities.

Packages

host dfu-util

host dosfstools

host e2fsprogs

host genext2fs

host genimage

host genpart

host lpc3250loader

host mtd, jffs2 and ubi/ubifs tools

host mtools

host omap-u-boot-utils

host openocd

host parted

host pwgen

host sam-ba

host squashfs

host sunxi-tools

host u-boot tools

host util-linux

host-e2tools

12.6. Deprecated features

The following features are marked as deprecated in Buildroot due to them being either too old or unmaintained. They will be removed at some point, so stop using them. Each deprecated symbol in kconfig depends on a symbol BR2_DEPRECATED_SINCE_xxxx_xx, which provides an indication of when the feature can be removed: features will not be removed within the year following deprecation. For example, a symbol depending on BR2_DEPRECATED_SINCE_2013_05 can be removed from 2014.05 onwards.

Features Location

AVR32

Target options → Target Architecture

mips I (generic)

Target options → Target Architecture Variant

mips II

Target options → Target Architecture Variant

mips III

Target options → Target Architecture Variant

mips IV

Target options → Target Architecture Variant

sstrip

Build options → strip command for binaries on target

Linux 3.9.x kernel headers

Toolchain → Kernel Headers

Enable Objective-C support

Toolchain

Enable Fortran support

Toolchain

Xilinx Little Endian Microblaze GNU Tools 14.3

Toolchain → Toolchain

Xilinx Little Endian Microblaze GNU Tools v2

Toolchain → Toolchain

Xilinx Big Endian Microblaze GNU Tools

Toolchain → Toolchain

Xilinx Big Endian Microblaze GNU Tools

Toolchain → Toolchain

bison

Target packages → Development tools

distcc

Target packages → Development tools

Install flex binary on target

Target packages → Development tools

m4

Target packages → Development tools

gob2

Target packages → Graphic libraries and applications (graphic/text)

blackbox

Target packages → Graphic libraries and applications (graphic/text)

v 0.8.x

Target packages → Interpreter languages and scripting → Haserl version

Custom Network Settings

Bootloaders