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SPDX-License-Identifier: CC-BY-SA-2.0-UK + +***************************************** +The Yocto Project Development Environment +***************************************** + +This chapter takes a look at the Yocto Project development environment. +The chapter provides Yocto Project Development environment concepts that +help you understand how work is accomplished in an open source +environment, which is very different as compared to work accomplished in +a closed, proprietary environment. + +Specifically, this chapter addresses open source philosophy, source +repositories, workflows, Git, and licensing. + +Open Source Philosophy +====================== + +Open source philosophy is characterized by software development directed +by peer production and collaboration through an active community of +developers. Contrast this to the more standard centralized development +models used by commercial software companies where a finite set of +developers produces a product for sale using a defined set of procedures +that ultimately result in an end product whose architecture and source +material are closed to the public. + +Open source projects conceptually have differing concurrent agendas, +approaches, and production. These facets of the development process can +come from anyone in the public (community) who has a stake in the +software project. The open source environment contains new copyright, +licensing, domain, and consumer issues that differ from the more +traditional development environment. In an open source environment, the +end product, source material, and documentation are all available to the +public at no cost. + +A benchmark example of an open source project is the Linux kernel, which +was initially conceived and created by Finnish computer science student +Linus Torvalds in 1991. Conversely, a good example of a non-open source +project is the Windows family of operating systems developed by +Microsoft Corporation. + +Wikipedia has a good historical description of the Open Source +Philosophy `here <http://en.wikipedia.org/wiki/Open_source>`__. You can +also find helpful information on how to participate in the Linux +Community +`here <https://www.kernel.org/doc/html/latest/process/index.html>`__. + +The Development Host +==================== + +A development host or :term:`Build Host` is key to +using the Yocto Project. Because the goal of the Yocto Project is to +develop images or applications that run on embedded hardware, +development of those images and applications generally takes place on a +system not intended to run the software - the development host. + +You need to set up a development host in order to use it with the Yocto +Project. Most find that it is best to have a native Linux machine +function as the development host. However, it is possible to use a +system that does not run Linux as its operating system as your +development host. When you have a Mac or Windows-based system, you can +set it up as the development host by using +`CROPS <https://github.com/crops/poky-container>`__, which leverages +`Docker Containers <https://www.docker.com/>`__. Once you take the steps +to set up a CROPS machine, you effectively have access to a shell +environment that is similar to what you see when using a Linux-based +development host. For the steps needed to set up a system using CROPS, +see the +":ref:`dev-manual/start:setting up to use cross platforms (crops)`" +section in +the Yocto Project Development Tasks Manual. + +If your development host is going to be a system that runs a Linux +distribution, steps still exist that you must take to prepare the system +for use with the Yocto Project. You need to be sure that the Linux +distribution on the system is one that supports the Yocto Project. You +also need to be sure that the correct set of host packages are installed +that allow development using the Yocto Project. For the steps needed to +set up a development host that runs Linux, see the +":ref:`dev-manual/start:setting up a native linux host`" +section in the Yocto Project Development Tasks Manual. + +Once your development host is set up to use the Yocto Project, several +methods exist for you to do work in the Yocto Project environment: + +- *Command Lines, BitBake, and Shells:* Traditional development in the + Yocto Project involves using the :term:`OpenEmbedded Build System`, + which uses + BitBake, in a command-line environment from a shell on your + development host. You can accomplish this from a host that is a + native Linux machine or from a host that has been set up with CROPS. + Either way, you create, modify, and build images and applications all + within a shell-based environment using components and tools available + through your Linux distribution and the Yocto Project. + + For a general flow of the build procedures, see the + ":ref:`dev-manual/common-tasks:building a simple image`" + section in the Yocto Project Development Tasks Manual. + +- *Board Support Package (BSP) Development:* Development of BSPs + involves using the Yocto Project to create and test layers that allow + easy development of images and applications targeted for specific + hardware. To development BSPs, you need to take some additional steps + beyond what was described in setting up a development host. + + The :doc:`/bsp-guide/index` provides BSP-related development + information. For specifics on development host preparation, see the + ":ref:`bsp-guide/bsp:preparing your build host to work with bsp layers`" + section in the Yocto Project Board Support Package (BSP) Developer's + Guide. + +- *Kernel Development:* If you are going to be developing kernels using + the Yocto Project you likely will be using ``devtool``. A workflow + using ``devtool`` makes kernel development quicker by reducing + iteration cycle times. + + The :doc:`/kernel-dev/index` provides kernel-related + development information. For specifics on development host + preparation, see the + ":ref:`kernel-dev/common:preparing the build host to work on the kernel`" + section in the Yocto Project Linux Kernel Development Manual. + +- *Using Toaster:* The other Yocto Project development method that + involves an interface that effectively puts the Yocto Project into + the background is Toaster. Toaster provides an interface to the + OpenEmbedded build system. The interface enables you to configure and + run your builds. Information about builds is collected and stored in + a database. You can use Toaster to configure and start builds on + multiple remote build servers. + + For steps that show you how to set up your development host to use + Toaster and on how to use Toaster in general, see the + :doc:`/toaster-manual/index`. + +Yocto Project Source Repositories +================================= + +The Yocto Project team maintains complete source repositories for all +Yocto Project files at :yocto_git:`/`. This web-based source +code browser is organized into categories by function such as IDE +Plugins, Matchbox, Poky, Yocto Linux Kernel, and so forth. From the +interface, you can click on any particular item in the "Name" column and +see the URL at the bottom of the page that you need to clone a Git +repository for that particular item. Having a local Git repository of +the :term:`Source Directory`, which +is usually named "poky", allows you to make changes, contribute to the +history, and ultimately enhance the Yocto Project's tools, Board Support +Packages, and so forth. + +For any supported release of Yocto Project, you can also go to the +:yocto_home:`Yocto Project Website <>` and select the "DOWNLOADS" +item from the "SOFTWARE" menu and get a released tarball of the ``poky`` +repository, any supported BSP tarball, or Yocto Project tools. Unpacking +these tarballs gives you a snapshot of the released files. + +.. note:: + + - The recommended method for setting up the Yocto Project + :term:`Source Directory` and the files + for supported BSPs (e.g., ``meta-intel``) is to use `Git <#git>`__ + to create a local copy of the upstream repositories. + + - Be sure to always work in matching branches for both the selected + BSP repository and the Source Directory (i.e. ``poky``) + repository. For example, if you have checked out the "master" + branch of ``poky`` and you are going to use ``meta-intel``, be + sure to checkout the "master" branch of ``meta-intel``. + +In summary, here is where you can get the project files needed for +development: + +- :yocto_git:`Source Repositories: <>` This area contains IDE + Plugins, Matchbox, Poky, Poky Support, Tools, Yocto Linux Kernel, and + Yocto Metadata Layers. You can create local copies of Git + repositories for each of these areas. + + .. image:: figures/source-repos.png + :align: center + + For steps on how to view and access these upstream Git repositories, + see the ":ref:`dev-manual/start:accessing source repositories`" + Section in the Yocto Project Development Tasks Manual. + +- :yocto_dl:`Index of /releases: </releases>` This is an index + of releases such as Poky, Pseudo, installers for cross-development + toolchains, miscellaneous support and all released versions of Yocto + Project in the form of images or tarballs. Downloading and extracting + these files does not produce a local copy of the Git repository but + rather a snapshot of a particular release or image. + + .. image:: figures/index-downloads.png + :align: center + + For steps on how to view and access these files, see the + ":ref:`dev-manual/start:accessing index of releases`" + section in the Yocto Project Development Tasks Manual. + +- *"DOWNLOADS" page for the* :yocto_home:`Yocto Project Website <>` *:* + + The Yocto Project website includes a "DOWNLOADS" page accessible + through the "SOFTWARE" menu that allows you to download any Yocto + Project release, tool, and Board Support Package (BSP) in tarball + form. The tarballs are similar to those found in the + :yocto_dl:`Index of /releases: </releases>` area. + + .. image:: figures/yp-download.png + :align: center + + For steps on how to use the "DOWNLOADS" page, see the + ":ref:`dev-manual/start:using the downloads page`" + section in the Yocto Project Development Tasks Manual. + +Git Workflows and the Yocto Project +=================================== + +Developing using the Yocto Project likely requires the use of +`Git <#git>`__. Git is a free, open source distributed version control +system used as part of many collaborative design environments. This +section provides workflow concepts using the Yocto Project and Git. In +particular, the information covers basic practices that describe roles +and actions in a collaborative development environment. + +.. note:: + + If you are familiar with this type of development environment, you + might not want to read this section. + +The Yocto Project files are maintained using Git in "branches" whose Git +histories track every change and whose structures provide branches for +all diverging functionality. Although there is no need to use Git, many +open source projects do so. + +For the Yocto Project, a key individual called the "maintainer" is +responsible for the integrity of the "master" branch of a given Git +repository. The "master" branch is the "upstream" repository from which +final or most recent builds of a project occur. The maintainer is +responsible for accepting changes from other developers and for +organizing the underlying branch structure to reflect release strategies +and so forth. + +.. note:: + + For information on finding out who is responsible for (maintains) a + particular area of code in the Yocto Project, see the + ":ref:`dev-manual/common-tasks:submitting a change to the yocto project`" + section of the Yocto Project Development Tasks Manual. + +The Yocto Project ``poky`` Git repository also has an upstream +contribution Git repository named ``poky-contrib``. You can see all the +branches in this repository using the web interface of the +:yocto_git:`Source Repositories <>` organized within the "Poky Support" +area. These branches hold changes (commits) to the project that have +been submitted or committed by the Yocto Project development team and by +community members who contribute to the project. The maintainer +determines if the changes are qualified to be moved from the "contrib" +branches into the "master" branch of the Git repository. + +Developers (including contributing community members) create and +maintain cloned repositories of upstream branches. The cloned +repositories are local to their development platforms and are used to +develop changes. When a developer is satisfied with a particular feature +or change, they "push" the change to the appropriate "contrib" +repository. + +Developers are responsible for keeping their local repository up-to-date +with whatever upstream branch they are working against. They are also +responsible for straightening out any conflicts that might arise within +files that are being worked on simultaneously by more than one person. +All this work is done locally on the development host before anything is +pushed to a "contrib" area and examined at the maintainer's level. + +A somewhat formal method exists by which developers commit changes and +push them into the "contrib" area and subsequently request that the +maintainer include them into an upstream branch. This process is called +"submitting a patch" or "submitting a change." For information on +submitting patches and changes, see the +":ref:`dev-manual/common-tasks:submitting a change to the yocto project`" +section in the Yocto Project Development Tasks Manual. + +In summary, a single point of entry exists for changes into a "master" +or development branch of the Git repository, which is controlled by the +project's maintainer. And, a set of developers exist who independently +develop, test, and submit changes to "contrib" areas for the maintainer +to examine. The maintainer then chooses which changes are going to +become a permanent part of the project. + +.. image:: figures/git-workflow.png + :align: center + +While each development environment is unique, there are some best +practices or methods that help development run smoothly. The following +list describes some of these practices. For more information about Git +workflows, see the workflow topics in the `Git Community +Book <http://book.git-scm.com>`__. + +- *Make Small Changes:* It is best to keep the changes you commit small + as compared to bundling many disparate changes into a single commit. + This practice not only keeps things manageable but also allows the + maintainer to more easily include or refuse changes. + +- *Make Complete Changes:* It is also good practice to leave the + repository in a state that allows you to still successfully build + your project. In other words, do not commit half of a feature, then + add the other half as a separate, later commit. Each commit should + take you from one buildable project state to another buildable state. + +- *Use Branches Liberally:* It is very easy to create, use, and delete + local branches in your working Git repository on the development + host. You can name these branches anything you like. It is helpful to + give them names associated with the particular feature or change on + which you are working. Once you are done with a feature or change and + have merged it into your local master branch, simply discard the + temporary branch. + +- *Merge Changes:* The ``git merge`` command allows you to take the + changes from one branch and fold them into another branch. This + process is especially helpful when more than a single developer might + be working on different parts of the same feature. Merging changes + also automatically identifies any collisions or "conflicts" that + might happen as a result of the same lines of code being altered by + two different developers. + +- *Manage Branches:* Because branches are easy to use, you should use a + system where branches indicate varying levels of code readiness. For + example, you can have a "work" branch to develop in, a "test" branch + where the code or change is tested, a "stage" branch where changes + are ready to be committed, and so forth. As your project develops, + you can merge code across the branches to reflect ever-increasing + stable states of the development. + +- *Use Push and Pull:* The push-pull workflow is based on the concept + of developers "pushing" local commits to a remote repository, which + is usually a contribution repository. This workflow is also based on + developers "pulling" known states of the project down into their + local development repositories. The workflow easily allows you to + pull changes submitted by other developers from the upstream + repository into your work area ensuring that you have the most recent + software on which to develop. The Yocto Project has two scripts named + ``create-pull-request`` and ``send-pull-request`` that ship with the + release to facilitate this workflow. You can find these scripts in + the ``scripts`` folder of the + :term:`Source Directory`. For information + on how to use these scripts, see the + ":ref:`dev-manual/common-tasks:using scripts to push a change upstream and request a pull`" + section in the Yocto Project Development Tasks Manual. + +- *Patch Workflow:* This workflow allows you to notify the maintainer + through an email that you have a change (or patch) you would like + considered for the "master" branch of the Git repository. To send + this type of change, you format the patch and then send the email + using the Git commands ``git format-patch`` and ``git send-email``. + For information on how to use these scripts, see the + ":ref:`dev-manual/common-tasks:submitting a change to the yocto project`" + section in the Yocto Project Development Tasks Manual. + +Git +=== + +The Yocto Project makes extensive use of Git, which is a free, open +source distributed version control system. Git supports distributed +development, non-linear development, and can handle large projects. It +is best that you have some fundamental understanding of how Git tracks +projects and how to work with Git if you are going to use the Yocto +Project for development. This section provides a quick overview of how +Git works and provides you with a summary of some essential Git +commands. + +.. note:: + + - For more information on Git, see + http://git-scm.com/documentation. + + - If you need to download Git, it is recommended that you add Git to + your system through your distribution's "software store" (e.g. for + Ubuntu, use the Ubuntu Software feature). For the Git download + page, see http://git-scm.com/download. + + - For information beyond the introductory nature in this section, + see the ":ref:`dev-manual/start:locating yocto project source files`" + section in the Yocto Project Development Tasks Manual. + +Repositories, Tags, and Branches +-------------------------------- + +As mentioned briefly in the previous section and also in the "`Git +Workflows and the Yocto +Project <#gs-git-workflows-and-the-yocto-project>`__" section, the Yocto +Project maintains source repositories at :yocto_git:`/`. If you +look at this web-interface of the repositories, each item is a separate +Git repository. + +Git repositories use branching techniques that track content change (not +files) within a project (e.g. a new feature or updated documentation). +Creating a tree-like structure based on project divergence allows for +excellent historical information over the life of a project. This +methodology also allows for an environment from which you can do lots of +local experimentation on projects as you develop changes or new +features. + +A Git repository represents all development efforts for a given project. +For example, the Git repository ``poky`` contains all changes and +developments for that repository over the course of its entire life. +That means that all changes that make up all releases are captured. The +repository maintains a complete history of changes. + +You can create a local copy of any repository by "cloning" it with the +``git clone`` command. When you clone a Git repository, you end up with +an identical copy of the repository on your development system. Once you +have a local copy of a repository, you can take steps to develop +locally. For examples on how to clone Git repositories, see the +":ref:`dev-manual/start:locating yocto project source files`" +section in the Yocto Project Development Tasks Manual. + +It is important to understand that Git tracks content change and not +files. Git uses "branches" to organize different development efforts. +For example, the ``poky`` repository has several branches that include +the current "&DISTRO_NAME_NO_CAP;" branch, the "master" branch, and many +branches for past Yocto Project releases. You can see all the branches +by going to :yocto_git:`/poky/` and clicking on the +``[...]`` link beneath the "Branch" heading. + +Each of these branches represents a specific area of development. The +"master" branch represents the current or most recent development. All +other branches represent offshoots of the "master" branch. + +When you create a local copy of a Git repository, the copy has the same +set of branches as the original. This means you can use Git to create a +local working area (also called a branch) that tracks a specific +development branch from the upstream source Git repository. in other +words, you can define your local Git environment to work on any +development branch in the repository. To help illustrate, consider the +following example Git commands: +:: + + $ cd ~ + $ git clone git://git.yoctoproject.org/poky + $ cd poky + $ git checkout -b &DISTRO_NAME_NO_CAP; origin/&DISTRO_NAME_NO_CAP; + +In the previous example +after moving to the home directory, the ``git clone`` command creates a +local copy of the upstream ``poky`` Git repository. By default, Git +checks out the "master" branch for your work. After changing the working +directory to the new local repository (i.e. ``poky``), the +``git checkout`` command creates and checks out a local branch named +"&DISTRO_NAME_NO_CAP;", which tracks the upstream +"origin/&DISTRO_NAME_NO_CAP;" branch. Changes you make while in this +branch would ultimately affect the upstream "&DISTRO_NAME_NO_CAP;" branch +of the ``poky`` repository. + +It is important to understand that when you create and checkout a local +working branch based on a branch name, your local environment matches +the "tip" of that particular development branch at the time you created +your local branch, which could be different from the files in the +"master" branch of the upstream repository. In other words, creating and +checking out a local branch based on the "&DISTRO_NAME_NO_CAP;" branch +name is not the same as checking out the "master" branch in the +repository. Keep reading to see how you create a local snapshot of a +Yocto Project Release. + +Git uses "tags" to mark specific changes in a repository branch +structure. Typically, a tag is used to mark a special point such as the +final change (or commit) before a project is released. You can see the +tags used with the ``poky`` Git repository by going to :yocto_git:`/poky/` +and clicking on the ``[...]`` link beneath the "Tag" heading. + +Some key tags for the ``poky`` repository are ``jethro-14.0.3``, +``morty-16.0.1``, ``pyro-17.0.0``, and +``&DISTRO_NAME_NO_CAP;-&POKYVERSION;``. These tags represent Yocto Project +releases. + +When you create a local copy of the Git repository, you also have access +to all the tags in the upstream repository. Similar to branches, you can +create and checkout a local working Git branch based on a tag name. When +you do this, you get a snapshot of the Git repository that reflects the +state of the files when the change was made associated with that tag. +The most common use is to checkout a working branch that matches a +specific Yocto Project release. Here is an example: +:: + + $ cd ~ + $ git clone git://git.yoctoproject.org/poky + $ cd poky + $ git fetch --tags + $ git checkout tags/rocko-18.0.0 -b my_rocko-18.0.0 + +In this example, the name +of the top-level directory of your local Yocto Project repository is +``poky``. After moving to the ``poky`` directory, the ``git fetch`` +command makes all the upstream tags available locally in your +repository. Finally, the ``git checkout`` command creates and checks out +a branch named "my-rocko-18.0.0" that is based on the upstream branch +whose "HEAD" matches the commit in the repository associated with the +"rocko-18.0.0" tag. The files in your repository now exactly match that +particular Yocto Project release as it is tagged in the upstream Git +repository. It is important to understand that when you create and +checkout a local working branch based on a tag, your environment matches +a specific point in time and not the entire development branch (i.e. +from the "tip" of the branch backwards). + +Basic Commands +-------------- + +Git has an extensive set of commands that lets you manage changes and +perform collaboration over the life of a project. Conveniently though, +you can manage with a small set of basic operations and workflows once +you understand the basic philosophy behind Git. You do not have to be an +expert in Git to be functional. A good place to look for instruction on +a minimal set of Git commands is +`here <http://git-scm.com/documentation>`__. + +The following list of Git commands briefly describes some basic Git +operations as a way to get started. As with any set of commands, this +list (in most cases) simply shows the base command and omits the many +arguments it supports. See the Git documentation for complete +descriptions and strategies on how to use these commands: + +- *git init:* Initializes an empty Git repository. You cannot use + Git commands unless you have a ``.git`` repository. + +- *git clone:* Creates a local clone of a Git repository that is on + equal footing with a fellow developer's Git repository or an upstream + repository. + +- *git add:* Locally stages updated file contents to the index that + Git uses to track changes. You must stage all files that have changed + before you can commit them. + +- *git commit:* Creates a local "commit" that documents the changes + you made. Only changes that have been staged can be committed. + Commits are used for historical purposes, for determining if a + maintainer of a project will allow the change, and for ultimately + pushing the change from your local Git repository into the project's + upstream repository. + +- *git status:* Reports any modified files that possibly need to be + staged and gives you a status of where you stand regarding local + commits as compared to the upstream repository. + +- *git checkout branch-name:* Changes your local working branch and + in this form assumes the local branch already exists. This command is + analogous to "cd". + +- *git checkout –b working-branch upstream-branch:* Creates and + checks out a working branch on your local machine. The local branch + tracks the upstream branch. You can use your local branch to isolate + your work. It is a good idea to use local branches when adding + specific features or changes. Using isolated branches facilitates + easy removal of changes if they do not work out. + +- *git branch:* Displays the existing local branches associated + with your local repository. The branch that you have currently + checked out is noted with an asterisk character. + +- *git branch -D branch-name:* Deletes an existing local branch. + You need to be in a local branch other than the one you are deleting + in order to delete branch-name. + +- *git pull --rebase:* Retrieves information from an upstream Git + repository and places it in your local Git repository. You use this + command to make sure you are synchronized with the repository from + which you are basing changes (.e.g. the "master" branch). The + "--rebase" option ensures that any local commits you have in your + branch are preserved at the top of your local branch. + +- *git push repo-name local-branch:upstream-branch:* Sends + all your committed local changes to the upstream Git repository that + your local repository is tracking (e.g. a contribution repository). + The maintainer of the project draws from these repositories to merge + changes (commits) into the appropriate branch of project's upstream + repository. + +- *git merge:* Combines or adds changes from one local branch of + your repository with another branch. When you create a local Git + repository, the default branch is named "master". A typical workflow + is to create a temporary branch that is based off "master" that you + would use for isolated work. You would make your changes in that + isolated branch, stage and commit them locally, switch to the + "master" branch, and then use the ``git merge`` command to apply the + changes from your isolated branch into the currently checked out + branch (e.g. "master"). After the merge is complete and if you are + done with working in that isolated branch, you can safely delete the + isolated branch. + +- *git cherry-pick commits:* Choose and apply specific commits from + one branch into another branch. There are times when you might not be + able to merge all the changes in one branch with another but need to + pick out certain ones. + +- *gitk:* Provides a GUI view of the branches and changes in your + local Git repository. This command is a good way to graphically see + where things have diverged in your local repository. + + .. note:: + + You need to install the + gitk + package on your development system to use this command. + +- *git log:* Reports a history of your commits to the repository. + This report lists all commits regardless of whether you have pushed + them upstream or not. + +- *git diff:* Displays line-by-line differences between a local + working file and the same file as understood by Git. This command is + useful to see what you have changed in any given file. + +Licensing +========= + +Because open source projects are open to the public, they have different +licensing structures in place. License evolution for both Open Source +and Free Software has an interesting history. If you are interested in +this history, you can find basic information here: + +- `Open source license + history <http://en.wikipedia.org/wiki/Open-source_license>`__ + +- `Free software license + history <http://en.wikipedia.org/wiki/Free_software_license>`__ + +In general, the Yocto Project is broadly licensed under the +Massachusetts Institute of Technology (MIT) License. MIT licensing +permits the reuse of software within proprietary software as long as the +license is distributed with that software. MIT is also compatible with +the GNU General Public License (GPL). Patches to the Yocto Project +follow the upstream licensing scheme. You can find information on the +MIT license +`here <http://www.opensource.org/licenses/mit-license.php>`__. You can +find information on the GNU GPL +`here <http://www.opensource.org/licenses/LGPL-3.0>`__. + +When you build an image using the Yocto Project, the build process uses +a known list of licenses to ensure compliance. You can find this list in +the :term:`Source Directory` at +``meta/files/common-licenses``. Once the build completes, the list of +all licenses found and used during that build are kept in the +:term:`Build Directory` at +``tmp/deploy/licenses``. + +If a module requires a license that is not in the base list, the build +process generates a warning during the build. These tools make it easier +for a developer to be certain of the licenses with which their shipped +products must comply. However, even with these tools it is still up to +the developer to resolve potential licensing issues. + +The base list of licenses used by the build process is a combination of +the Software Package Data Exchange (SPDX) list and the Open Source +Initiative (OSI) projects. `SPDX Group <http://spdx.org>`__ is a working +group of the Linux Foundation that maintains a specification for a +standard format for communicating the components, licenses, and +copyrights associated with a software package. +`OSI <http://opensource.org>`__ is a corporation dedicated to the Open +Source Definition and the effort for reviewing and approving licenses +that conform to the Open Source Definition (OSD). + +You can find a list of the combined SPDX and OSI licenses that the Yocto +Project uses in the ``meta/files/common-licenses`` directory in your +:term:`Source Directory`. + +For information that can help you maintain compliance with various open +source licensing during the lifecycle of a product created using the +Yocto Project, see the +":ref:`dev-manual/common-tasks:maintaining open source license compliance during your product's lifecycle`" +section in the Yocto Project Development Tasks Manual. |