%poky; ] > This chapter lists common variables used in the OpenEmbedded build system and gives an overview of their function and contents. A B C D E F G H I K L M O P R S T U V W X ABIEXTENSION ABIEXTENSION[doc] = "Extension to the Application Binary Interface (ABI) field of the GNU canonical architecture name (e.g. "eabi")." Extension to the Application Binary Interface (ABI) field of the GNU canonical architecture name (e.g. "eabi"). ABI extensions are set in the machine include files. For example, the meta/conf/machine/include/arm/arch-arm.inc file sets the following extension: ABIEXTENSION = "eabi" ALLOW_EMPTY ALLOW_EMPTY[doc] = "Specifies if an output package should still be produced if it is empty." Specifies if an output package should still be produced if it is empty. By default, BitBake does not produce empty packages. This default behavior can cause issues when there is an RDEPENDS or some other hard runtime requirement on the existence of the package. Like all package-controlling variables, you must always use them in conjunction with a package name override, as in: ALLOW_EMPTY_${PN} = "1" ALLOW_EMPTY_${PN}-dev = "1" ALLOW_EMPTY_${PN}-staticdev = "1" ALTERNATIVE ALTERNATIVE[doc] = "Lists commands in a package that need an alternative binary naming scheme." Lists commands in a package that need an alternative binary naming scheme. Sometimes the same command is provided in multiple packages. When this occurs, the OpenEmbedded build system needs to use the alternatives system to create a different binary naming scheme so the commands can co-exist. To use the variable, list out the package's commands that also exist as part of another package. For example, if the busybox package has four commands that also exist as part of another package, you identify them as follows: ALTERNATIVE_busybox = "sh sed test bracket" For more information on the alternatives system, see the "update-alternatives.bbclass" section. ALTERNATIVE_LINK_NAME ALTERNATIVE_LINK_NAME[doc] = "Used by the alternatives system to map duplicated commands to actual locations." Used by the alternatives system to map duplicated commands to actual locations. For example, if the bracket command provided by the busybox package is duplicated through another package, you must use the ALTERNATIVE_LINK_NAME variable to specify the actual location: ALTERNATIVE_LINK_NAME[bracket] = "/usr/bin/[" In this example, the binary for the bracket command (i.e. [) from the busybox package resides in /usr/bin/. If ALTERNATIVE_LINK_NAME is not defined, it defaults to ${bindir}/name. For more information on the alternatives system, see the "update-alternatives.bbclass" section. ALTERNATIVE_PRIORITY ALTERNATIVE_PRIORITY[doc] = "Used by the alternatives system to create default priorities for duplicated commands." Used by the alternatives system to create default priorities for duplicated commands. You can use the variable to create a single default regardless of the command name or package, a default for specific duplicated commands regardless of the package, or a default for specific commands tied to particular packages. Here are the available syntax forms: ALTERNATIVE_PRIORITY = "priority" ALTERNATIVE_PRIORITY[name] = "priority" ALTERNATIVE_PRIORITY_pkg[name] = "priority" For more information on the alternatives system, see the "update-alternatives.bbclass" section. ALTERNATIVE_TARGET ALTERNATIVE_TARGET[doc] = "Used by the alternatives system to create default link locations for duplicated commands." Used by the alternatives system to create default link locations for duplicated commands. You can use the variable to create a single default location for all duplicated commands regardless of the command name or package, a default for specific duplicated commands regardless of the package, or a default for specific commands tied to particular packages. Here are the available syntax forms: ALTERNATIVE_TARGET = "target" ALTERNATIVE_TARGET[name] = "target" ALTERNATIVE_TARGET_pkg[name] = "target" If ALTERNATIVE_TARGET is not defined, it inherits the value from the ALTERNATIVE_LINK_NAME variable. If ALTERNATIVE_LINK_NAME and ALTERNATIVE_TARGET are the same, the target for ALTERNATIVE_TARGET has ".{BPN}" appended to it. Finally, if the file referenced has not been renamed, the alternatives system will rename it to avoid the need to rename alternative files in the do_install task while retaining support for the command if necessary. For more information on the alternatives system, see the "update-alternatives.bbclass" section. APPEND APPEND[doc] = "An override list of append strings for each LABEL." An override list of append strings for each LABEL. See the grub-efi class for more information on how this variable is used. AR AR[doc] = "Minimal command and arguments to run 'ar'." The minimal command and arguments used to run ar. ARCHIVER_MODE ARCHIVER_MODE[doc] = "Controls archive creation used when releasing source files." When used with the archiver class, determines the type of information used to create a released archive. You can use this variable to create archives of patched source, original source, configured source, and so forth by employing the following variable flags (varflags): ARCHIVER_MODE[src] = "original" # Uses original (unpacked) source # files. ARCHIVER_MODE[src] = "patched" # Uses patched source files. This is # the default. ARCHIVER_MODE[src] = "configured" # Uses configured source files. ARCHIVER_MODE[diff] = "1" # Uses patches between do_unpack and # do_patch. ARCHIVER_MODE[diff-exclude] ?= "file file ..." # Lists files and directories to # exclude from diff. ARCHIVER_MODE[dumpdata] = "1" # Uses environment data. ARCHIVER_MODE[recipe] = "1" # Uses recipe and include files. ARCHIVER_MODE[srpm] = "1" # Uses RPM package files. For information on how the variable works, see the meta/classes/archiver.bbclass file in the Source Directory. AS AS[doc] = "Minimal command and arguments to run the assembler." The minimal command and arguments used to run the assembler. ASSUME_PROVIDED ASSUME_PROVIDED[doc] = "Lists recipe names (PN values) BitBake does not attempt to build." Lists recipe names (PN values) BitBake does not attempt to build. Instead, BitBake assumes these recipes have already been built. In OpenEmbedded Core, ASSUME_PROVIDED mostly specifies native tools that should not be built. An example is git-native, which when specified, allows for the Git binary from the host to be used rather than building git-native. ASSUME_SHLIBS ASSUME_SHLIBS[doc] = Provides additional shlibs provider mapping information, which adds to or overwrites the information provided automatically by the system." Provides additional shlibs provider mapping information, which adds to or overwrites the information provided automatically by the system. Separate multiple entries using spaces. As an example, use the following form to add an shlib provider of shlibname in packagename with the optional version: shlibname:packagename[_version] Here is an example that adds a shared library named libEGL.so.1 as being provided by the libegl-implementation package: ASSUME_SHLIBS = "libEGL.so.1:libegl-implementation" AUTHOR AUTHOR[doc] = "Email address used to contact the original author or authors in order to send patches and forward bugs." The email address used to contact the original author or authors in order to send patches and forward bugs. AUTO_LIBNAME_PKGS AUTO_LIBNAME_PKGS[doc] = "Specifies which packages should be checked for libraries and renamed according to Debian library package naming." When the debian class is inherited, which is the default behavior, AUTO_LIBNAME_PKGS specifies which packages should be checked for libraries and renamed according to Debian library package naming. The default value is "${PACKAGES}", which causes the debian class to act on all packages that are explicitly generated by the recipe. AUTO_SYSLINUXMENU AUTO_SYSLINUXMENU[doc] = "Enables creating an automatic menu for the syslinux bootloader." Enables creating an automatic menu for the syslinux bootloader. You must set this variable in your recipe. The syslinux class checks this variable. AUTOREV AUTOREV[doc] = "When SRCREV is set to the value of this variable, it specifies to use the latest source revision in the repository." When SRCREV is set to the value of this variable, it specifies to use the latest source revision in the repository. Here is an example: SRCREV = "${AUTOREV}" If you use the previous statement to retrieve the latest version of software, you need to be sure PV contains ${SRCPV}. For example, suppose you have a kernel recipe that inherits the kernel class and you use the previous statement. In this example, ${SRCPV} does not automatically get into PV. Consequently, you need to change PV in your recipe so that it does contain ${SRCPV}. For more information see the "Automatically Incrementing a Binary Package Revision Number" section in the Yocto Project Development Manual. AVAILTUNES AVAILTUNES[doc] = "The list of defined CPU and Application Binary Interface (ABI) tunings (i.e. "tunes") available for use by the OpenEmbedded build system." The list of defined CPU and Application Binary Interface (ABI) tunings (i.e. "tunes") available for use by the OpenEmbedded build system. The list simply presents the tunes that are available. Not all tunes may be compatible with a particular machine configuration, or with each other in a Multilib configuration. To add a tune to the list, be sure to append it with spaces using the "+=" BitBake operator. Do not simply replace the list by using the "=" operator. See the "Basic Syntax" section in the BitBake User Manual for more information. B B[doc] = "The Build Directory. The OpenEmbedded build system places generated objects into the Build Directory during a recipe's build process." The directory within the Build Directory in which the OpenEmbedded build system places generated objects during a recipe's build process. By default, this directory is the same as the S directory, which is defined as: S = "${WORKDIR}/${BP}" You can separate the (S) directory and the directory pointed to by the B variable. Most Autotools-based recipes support separating these directories. The build system defaults to using separate directories for gcc and some kernel recipes. BAD_RECOMMENDATIONS BAD_RECOMMENDATIONS[doc] = "A list of packages not to install despite being recommended by a recipe. Support for this variable exists only when using the IPK packaging backend." Lists "recommended-only" packages to not install. Recommended-only packages are packages installed only through the RRECOMMENDS variable. You can prevent any of these "recommended" packages from being installed by listing them with the BAD_RECOMMENDATIONS variable: BAD_RECOMMENDATIONS = "package_name package_name package_name ..." You can set this variable globally in your local.conf file or you can attach it to a specific image recipe by using the recipe name override: BAD_RECOMMENDATIONS_pn-target_image = "package_name" It is important to realize that if you choose to not install packages using this variable and some other packages are dependent on them (i.e. listed in a recipe's RDEPENDS variable), the OpenEmbedded build system ignores your request and will install the packages to avoid dependency errors. Support for this variable exists only when using the IPK and RPM packaging backend. Support does not exist for DEB. See the NO_RECOMMENDATIONS and the PACKAGE_EXCLUDE variables for related information. BASE_LIB BASE_LIB[doc] = "The library directory name for the CPU or Application Binary Interface (ABI) tune." The library directory name for the CPU or Application Binary Interface (ABI) tune. The BASE_LIB applies only in the Multilib context. See the "Combining Multiple Versions of Library Files into One Image" section in the Yocto Project Development Manual for information on Multilib. The BASE_LIB variable is defined in the machine include files in the Source Directory. If Multilib is not being used, the value defaults to "lib". BASE_WORKDIR BASE_WORKDIR[doc] = "Points to the base of the work directory for all recipes." Points to the base of the work directory for all recipes. The default value is "${TMPDIR}/work". BB_ALLOWED_NETWORKS BB_ALLOWED_NETWORKS[doc] = "A list of hosts that the fetcher is allowed to use to obtain the required source code." Specifies a space-delimited list of hosts that the fetcher is allowed to use to obtain the required source code. Following are considerations surrounding this variable: This host list is only used if BB_NO_NETWORK is either not set or set to "0". Limited support for wildcard matching against the beginning of host names exists. For example, the following setting matches git.gnu.org, ftp.gnu.org, and foo.git.gnu.org. BB_ALLOWED_NETWORKS = "*.gnu.org" Mirrors not in the host list are skipped and logged in debug. Attempts to access networks not in the host list cause a failure. Using BB_ALLOWED_NETWORKS in conjunction with PREMIRRORS is very useful. Adding the host you want to use to PREMIRRORS results in the source code being fetched from an allowed location and avoids raising an error when a host that is not allowed is in a SRC_URI statement. This is because the fetcher does not attempt to use the host listed in SRC_URI after a successful fetch from the PREMIRRORS occurs. BB_DANGLINGAPPENDS_WARNONLY BB_DANGLINGAPPENDS_WARNONLY[doc] = "Defines how BitBake handles situations where an append file (.bbappend) has no corresponding recipe file (.bb)." Defines how BitBake handles situations where an append file (.bbappend) has no corresponding recipe file (.bb). This condition often occurs when layers get out of sync (e.g. oe-core bumps a recipe version and the old recipe no longer exists and the other layer has not been updated to the new version of the recipe yet). The default fatal behavior is safest because it is the sane reaction given something is out of sync. It is important to realize when your changes are no longer being applied. You can change the default behavior by setting this variable to "1", "yes", or "true" in your local.conf file, which is located in the Build Directory: Here is an example: BB_DANGLINGAPPENDS_WARNONLY = "1" BB_DISKMON_DIRS BB_DISKMON_DIRS[doc] = "Monitors disk space and available inodes during the build and allows you to control the build based on these parameters." Monitors disk space and available inodes during the build and allows you to control the build based on these parameters. Disk space monitoring is disabled by default. To enable monitoring, add the BB_DISKMON_DIRS variable to your conf/local.conf file found in the Build Directory. Use the following form: BB_DISKMON_DIRS = "action,dir,threshold [...]" where: action is: ABORT: Immediately abort the build when a threshold is broken. STOPTASKS: Stop the build after the currently executing tasks have finished when a threshold is broken. WARN: Issue a warning but continue the build when a threshold is broken. Subsequent warnings are issued as defined by the BB_DISKMON_WARNINTERVAL variable, which must be defined in the conf/local.conf file. dir is: Any directory you choose. You can specify one or more directories to monitor by separating the groupings with a space. If two directories are on the same device, only the first directory is monitored. threshold is: Either the minimum available disk space, the minimum number of free inodes, or both. You must specify at least one. To omit one or the other, simply omit the value. Specify the threshold using G, M, K for Gbytes, Mbytes, and Kbytes, respectively. If you do not specify G, M, or K, Kbytes is assumed by default. Do not use GB, MB, or KB. Here are some examples: BB_DISKMON_DIRS = "ABORT,${TMPDIR},1G,100K WARN,${SSTATE_DIR},1G,100K" BB_DISKMON_DIRS = "STOPTASKS,${TMPDIR},1G" BB_DISKMON_DIRS = "ABORT,${TMPDIR},,100K" The first example works only if you also provide the BB_DISKMON_WARNINTERVAL variable in the conf/local.conf. This example causes the build system to immediately abort when either the disk space in ${TMPDIR} drops below 1 Gbyte or the available free inodes drops below 100 Kbytes. Because two directories are provided with the variable, the build system also issue a warning when the disk space in the ${SSTATE_DIR} directory drops below 1 Gbyte or the number of free inodes drops below 100 Kbytes. Subsequent warnings are issued during intervals as defined by the BB_DISKMON_WARNINTERVAL variable. The second example stops the build after all currently executing tasks complete when the minimum disk space in the ${TMPDIR} directory drops below 1 Gbyte. No disk monitoring occurs for the free inodes in this case. The final example immediately aborts the build when the number of free inodes in the ${TMPDIR} directory drops below 100 Kbytes. No disk space monitoring for the directory itself occurs in this case. BB_DISKMON_WARNINTERVAL BB_DISKMON_WARNINTERVAL[doc] = "Defines the disk space and free inode warning intervals. To set these intervals, define the variable in the conf/local.conf file in the Build Directory." Defines the disk space and free inode warning intervals. To set these intervals, define the variable in your conf/local.conf file in the Build Directory. If you are going to use the BB_DISKMON_WARNINTERVAL variable, you must also use the BB_DISKMON_DIRS variable and define its action as "WARN". During the build, subsequent warnings are issued each time disk space or number of free inodes further reduces by the respective interval. If you do not provide a BB_DISKMON_WARNINTERVAL variable and you do use BB_DISKMON_DIRS with the "WARN" action, the disk monitoring interval defaults to the following: BB_DISKMON_WARNINTERVAL = "50M,5K" When specifying the variable in your configuration file, use the following form: BB_DISKMON_WARNINTERVAL = "disk_space_interval,disk_inode_interval" where: disk_space_interval is: An interval of memory expressed in either G, M, or K for Gbytes, Mbytes, or Kbytes, respectively. You cannot use GB, MB, or KB. disk_inode_interval is: An interval of free inodes expressed in either G, M, or K for Gbytes, Mbytes, or Kbytes, respectively. You cannot use GB, MB, or KB. Here is an example: BB_DISKMON_DIRS = "WARN,${SSTATE_DIR},1G,100K" BB_DISKMON_WARNINTERVAL = "50M,5K" These variables cause the OpenEmbedded build system to issue subsequent warnings each time the available disk space further reduces by 50 Mbytes or the number of free inodes further reduces by 5 Kbytes in the ${SSTATE_DIR} directory. Subsequent warnings based on the interval occur each time a respective interval is reached beyond the initial warning (i.e. 1 Gbytes and 100 Kbytes). BB_GENERATE_MIRROR_TARBALLS BB_GENERATE_MIRROR_TARBALLS[doc] = "Causes tarballs of the Git repositories to be placed in the DL_DIR directory." Causes tarballs of the Git repositories, including the Git metadata, to be placed in the DL_DIR directory. For performance reasons, creating and placing tarballs of the Git repositories is not the default action by the OpenEmbedded build system. BB_GENERATE_MIRROR_TARBALLS = "1" Set this variable in your local.conf file in the Build Directory. BB_NUMBER_THREADS BB_NUMBER_THREADS[doc] = "The maximum number of tasks BitBake should run in parallel at any one time. This variable is automatically configured to be equal to the number of build system cores." The maximum number of tasks BitBake should run in parallel at any one time. The OpenEmbedded build system automatically configures this variable to be equal to the number of cores on the build system. For example, a system with a dual core processor that also uses hyper-threading causes the BB_NUMBER_THREADS variable to default to "4". For single socket systems (i.e. one CPU), you should not have to override this variable to gain optimal parallelism during builds. However, if you have very large systems that employ multiple physical CPUs, you might want to make sure the BB_NUMBER_THREADS variable is not set higher than "20". For more information on speeding up builds, see the "Speeding Up the Build" section. BBCLASSEXTEND BBCLASSEXTEND[doc] = "Allows you to extend a recipe so that it builds variants of the software. Common variants for recipes are 'native', 'cross', 'nativesdk' and multilibs." Allows you to extend a recipe so that it builds variants of the software. Common variants for recipes exist such as "natives" like quilt-native, which is a copy of Quilt built to run on the build system; "crosses" such as gcc-cross, which is a compiler built to run on the build machine but produces binaries that run on the target MACHINE; "nativesdk", which targets the SDK machine instead of MACHINE; and "mulitlibs" in the form "multilib:multilib_name". To build a different variant of the recipe with a minimal amount of code, it usually is as simple as adding the following to your recipe: BBCLASSEXTEND =+ "native nativesdk" BBCLASSEXTEND =+ "multilib:multilib_name" Internally, the BBCLASSEXTEND mechanism generates recipe variants by rewriting variable values and applying overrides such as _class-native. For example, to generate a native version of a recipe, a DEPENDS on "foo" is rewritten to a DEPENDS on "foo-native". Even when using BBCLASSEXTEND, the recipe is only parsed once. Parsing once adds some limitations. For example, it is not possible to include a different file depending on the variant, since include statements are processed when the recipe is parsed. BBFILE_COLLECTIONS BBFILE_COLLECTIONS[doc] = "Lists the names of configured layers. These names are used to find the other BBFILE_* variables." Lists the names of configured layers. These names are used to find the other BBFILE_* variables. Typically, each layer will append its name to this variable in its conf/layer.conf file. BBFILE_PATTERN BBFILE_PATTERN[doc] = "Variable that expands to match files from BBFILES in a particular layer. This variable is used in the layer.conf file and must be suffixed with the name of a layer." Variable that expands to match files from BBFILES in a particular layer. This variable is used in the conf/layer.conf file and must be suffixed with the name of the specific layer (e.g. BBFILE_PATTERN_emenlow). BBFILE_PRIORITY BBFILE_PRIORITY[doc] = "Assigns the priority for recipe files in each layer. Setting this variable allows you to prioritize a layer against other layers that contain the same recipe." Assigns the priority for recipe files in each layer. This variable is useful in situations where the same recipe appears in more than one layer. Setting this variable allows you to prioritize a layer against other layers that contain the same recipe - effectively letting you control the precedence for the multiple layers. The precedence established through this variable stands regardless of a recipe's version (PV variable). For example, a layer that has a recipe with a higher PV value but for which the BBFILE_PRIORITY is set to have a lower precedence still has a lower precedence. A larger value for the BBFILE_PRIORITY variable results in a higher precedence. For example, the value 6 has a higher precedence than the value 5. If not specified, the BBFILE_PRIORITY variable is set based on layer dependencies (see the LAYERDEPENDS variable for more information. The default priority, if unspecified for a layer with no dependencies, is the lowest defined priority + 1 (or 1 if no priorities are defined). You can use the command bitbake-layers show-layers to list all configured layers along with their priorities. BBFILES BBFILES[doc] = "List of recipe files used by BitBake to build software." List of recipe files used by BitBake to build software. BBINCLUDELOGS BBINCLUDELOGS[doc] = "Variable that controls how BitBake displays logs on build failure." Variable that controls how BitBake displays logs on build failure. BBINCLUDELOGS_LINES BBINCLUDELOGS_LINES[doc] = "Amount of log lines printed on failure." If BBINCLUDELOGS is set, specifies the maximum number of lines from the task log file to print when reporting a failed task. If you do not set BBINCLUDELOGS_LINES, the entire log is printed. BBLAYERS BBLAYERS[doc] = "Lists the layers to enable during the build. This variable is defined in the bblayers.conf configuration file." Lists the layers to enable during the build. This variable is defined in the bblayers.conf configuration file in the Build Directory. Here is an example: BBLAYERS = " \ /home/scottrif/poky/meta \ /home/scottrif/poky/meta-poky \ /home/scottrif/poky/meta-yocto-bsp \ /home/scottrif/poky/meta-mykernel \ " This example enables four layers, one of which is a custom, user-defined layer named meta-mykernel. BBMASK BBMASK[doc] = "Prevents BitBake from processing specific recipes or recipe append files." Prevents BitBake from processing recipes and recipe append files. You can use the BBMASK variable to "hide" these .bb and .bbappend files. BitBake ignores any recipe or recipe append files that match any of the expressions. It is as if BitBake does not see them at all. Consequently, matching files are not parsed or otherwise used by BitBake. The values you provide are passed to Python's regular expression compiler. The expressions are compared against the full paths to the files. For complete syntax information, see Python's documentation at . The following example uses a complete regular expression to tell BitBake to ignore all recipe and recipe append files in the meta-ti/recipes-misc/ directory: BBMASK = "meta-ti/recipes-misc/" If you want to mask out multiple directories or recipes, you can specify multiple regular expression fragments. This next example masks out multiple directories and individual recipes: BBMASK += "/meta-ti/recipes-misc/ meta-ti/recipes-ti/packagegroup/" BBMASK += "/meta-oe/recipes-support/" BBMASK += "/meta-foo/.*/openldap" BBMASK += "opencv.*\.bbappend" BBMASK += "lzma" When specifying a directory name, use the trailing slash character to ensure you match just that directory name. BBMULTICONFIG BBMULTICONFIG[doc] = "Specifies each separate configuration when you are building targets with multiple configurations." Specifies each separate configuration when you are building targets with multiple configurations. Use this variable in your conf/local.conf configuration file. Specify a multiconfigname for each configuration file you are using. For example, the following line specifies three configuration files: BBMULTIFONFIG = "configA configB configC" Each configuration file you use must reside in the Build Directory's conf/multiconfig directory (e.g. build_directory/conf/multiconfig/configA.conf). For information on how to use BBMULTICONFIG in an environment that supports building targets with multiple configurations, see the "Building Targets with Multiple Configurations" section in the Yocto Project Development Manual. BBPATH BBPATH[doc] = "Used by BitBake to locate .bbclass and configuration files. This variable is analogous to the PATH variable." Used by BitBake to locate .bbclass and configuration files. This variable is analogous to the PATH variable. If you run BitBake from a directory outside of the Build Directory, you must be sure to set BBPATH to point to the Build Directory. Set the variable as you would any environment variable and then run BitBake: $ BBPATH = "build_directory" $ export BBPATH $ bitbake target BBSERVER BBSERVER[doc] = "Points to the server that runs memory-resident BitBake." Points to the server that runs memory-resident BitBake. This variable is set by the oe-init-build-env-memres setup script and should not be hand-edited. The variable is only used when you employ memory-resident BitBake. The setup script exports the value as follows: export BBSERVER=localhost:$port For more information on how the BBSERVER is used, see the oe-init-build-env-memres script, which is located in the Source Directory. BINCONFIG BINCONFIG[doc] = "When inheriting the binconfig-disabled class, this variable specifies binary configuration scripts to disable in favor of using pkg-config to query the information." When inheriting the binconfig-disabled class, this variable specifies binary configuration scripts to disable in favor of using pkg-config to query the information. The binconfig-disabled class will modify the specified scripts to return an error so that calls to them can be easily found and replaced. To add multiple scripts, separate them by spaces. Here is an example from the libpng recipe: BINCONFIG = "${bindir}/libpng-config ${bindir}/libpng16-config" BINCONFIG_GLOB BINCONFIG_GLOB[doc] = "When inheriting binconfig.bbclass from a recipe, this variable specifies a wildcard for configuration scripts that need editing." When inheriting the binconfig class, this variable specifies a wildcard for configuration scripts that need editing. The scripts are edited to correct any paths that have been set up during compilation so that they are correct for use when installed into the sysroot and called by the build processes of other recipes. For more information on how this variable works, see meta/classes/binconfig.bbclass in the Source Directory. You can also find general information on the class in the "binconfig.bbclass" section. BP BP[doc] = "The base recipe name and version but without any special recipe name suffix (i.e. -native, lib64-, and so forth). BP is comprised of ${BPN}-${PV}" The base recipe name and version but without any special recipe name suffix (i.e. -native, lib64-, and so forth). BP is comprised of the following: ${BPN}-${PV} BPN BPN[doc] = "This variable is a version of the PN variable but removes common suffixes and prefixes." This variable is a version of the PN variable with common prefixes and suffixes removed, such as nativesdk-, -cross, -native, and multilib's lib64- and lib32-. The exact lists of prefixes and suffixes removed are specified by the MLPREFIX and SPECIAL_PKGSUFFIX variables, respectively. BUGTRACKER BUGTRACKER[doc] = "Specifies a URL for an upstream bug tracking website for a recipe." Specifies a URL for an upstream bug tracking website for a recipe. The OpenEmbedded build system does not use this variable. Rather, the variable is a useful pointer in case a bug in the software being built needs to be manually reported. BUILD_ARCH BUILD_ARCH[doc] = "The name of the building architecture (e.g. i686)." Specifies the architecture of the build host (e.g. i686). The OpenEmbedded build system sets the value of BUILD_ARCH from the machine name reported by the uname command. BUILD_CFLAGS BUILD_CFLAGS[doc] = "Specifies the flags to pass to the C compiler when building for the build host." Specifies the flags to pass to the C compiler when building for the build host. When building in the -native context, CFLAGS is set to the value of this variable by default. BUILD_CPPFLAGS BUILD_CPPFLAGS[doc] = "Specifies the flags to pass to the C pre-processor (i.e. to both the C and the C++ compilers) when building for the build host." Specifies the flags to pass to the C pre-processor (i.e. to both the C and the C++ compilers) when building for the build host. When building in the -native context, CPPFLAGS is set to the value of this variable by default. BUILD_CXXFLAGS BUILD_CXXFLAGS[doc] = "Specifies the flags to pass to the C++ compiler when building for the build host." Specifies the flags to pass to the C++ compiler when building for the build host. When building in the -native context, CXXFLAGS is set to the value of this variable by default. BUILD_LDFLAGS BUILD_LDFLAGS[doc] = "Specifies the flags to pass to the linker when building for the build host." Specifies the flags to pass to the linker when building for the build host. When building in the -native context, LDFLAGS is set to the value of this variable by default. BUILD_OPTIMIZATION BUILD_OPTIMIZATION[doc] = "Specifies the optimization flags passed to the C compiler when building for the build host or the SDK." Specifies the optimization flags passed to the C compiler when building for the build host or the SDK. The flags are passed through the BUILD_CFLAGS and BUILDSDK_CFLAGS default values. The default value of the BUILD_OPTIMIZATION variable is "-O2 -pipe". BUILD_OS BUILD_OS[doc] = "The operating system (in lower case) of the building architecture (e.g. Linux)." Specifies the operating system in use on the build host (e.g. "linux"). The OpenEmbedded build system sets the value of BUILD_OS from the OS reported by the uname command - the first word, converted to lower-case characters. BUILD_PREFIX BUILD_PREFIX[doc] = "The toolchain binary prefix used for native recipes." The toolchain binary prefix used for native recipes. The OpenEmbedded build system uses the BUILD_PREFIX value to set the TARGET_PREFIX when building for native recipes. BUILD_SYS BUILD_SYS[doc] = "The toolchain binary prefix used for native recipes." Specifies the system, including the architecture and the operating system, to use when building for the build host (i.e. when building native recipes). The OpenEmbedded build system automatically sets this variable based on BUILD_ARCH, BUILD_VENDOR, and BUILD_OS. You do not need to set the BUILD_SYS variable yourself. BUILD_VENDOR BUILD_VENDOR[doc] = "The vendor name to use when building for the build host." Specifies the vendor name to use when building for the build host. The default value is an empty string (""). BUILDDIR BUILDDIR[doc] = "Points to the location of the Build Directory." Points to the location of the Build Directory. You can define this directory indirectly through the &OE_INIT_FILE; and oe-init-build-env-memres scripts by passing in a Build Directory path when you run the scripts. If you run the scripts and do not provide a Build Directory path, the BUILDDIR defaults to build in the current directory. BUILDHISTORY_COMMIT BUILDHISTORY_COMMIT[doc] = "When inheriting the buildhistory class, this variable specifies whether or not to commit the build history output in a local Git repository." When inheriting the buildhistory class, this variable specifies whether or not to commit the build history output in a local Git repository. If set to "1", this local repository will be maintained automatically by the buildhistory class and a commit will be created on every build for changes to each top-level subdirectory of the build history output (images, packages, and sdk). If you want to track changes to build history over time, you should set this value to "1". By default, the buildhistory class does not commit the build history output in a local Git repository: BUILDHISTORY_COMMIT ?= "0" BUILDHISTORY_COMMIT_AUTHOR BUILDHISTORY_COMMIT_AUTHOR[doc] = "When inheriting the buildhistory class, this variable specifies the author to use for each Git commit." When inheriting the buildhistory class, this variable specifies the author to use for each Git commit. In order for the BUILDHISTORY_COMMIT_AUTHOR variable to work, the BUILDHISTORY_COMMIT variable must be set to "1". Git requires that the value you provide for the BUILDHISTORY_COMMIT_AUTHOR variable takes the form of "name <email@host>". Providing an email address or host that is not valid does not produce an error. By default, the buildhistory class sets the variable as follows: BUILDHISTORY_COMMIT_AUTHOR ?= "buildhistory <buildhistory@${DISTRO}>" BUILDHISTORY_DIR BUILDHISTORY_DIR[doc] = "When inheriting the buildhistory class, this variable specifies the directory in which build history information is kept." When inheriting the buildhistory class, this variable specifies the directory in which build history information is kept. For more information on how the variable works, see the buildhistory.class. By default, the buildhistory class sets the directory as follows: BUILDHISTORY_DIR ?= "${TOPDIR}/buildhistory" BUILDHISTORY_FEATURES BUILDHISTORY_FEATURES[doc] = "When inheriting the buildhistory class, this variable specifies the build history features to be enabled." When inheriting the buildhistory class, this variable specifies the build history features to be enabled. For more information on how build history works, see the "Maintaining Build Output Quality" section. You can specify three features in the form of a space-separated list: image: Analysis of the contents of images, which includes the list of installed packages among other things. package: Analysis of the contents of individual packages. sdk: Analysis of the contents of the software development kit (SDK). By default, the buildhistory class enables all three features: BUILDHISTORY_FEATURES ?= "image package sdk" BUILDHISTORY_IMAGE_FILES BUILDHISTORY_IMAGE_FILES[doc] = "When inheriting the buildhistory class, this variable specifies a list of paths to files copied from the image contents into the build history directory under an "image-files" directory in the directory for the image, so that you can track the contents of each file." When inheriting the buildhistory class, this variable specifies a list of paths to files copied from the image contents into the build history directory under an "image-files" directory in the directory for the image, so that you can track the contents of each file. The default is to copy /etc/passwd and /etc/group, which allows you to monitor for changes in user and group entries. You can modify the list to include any file. Specifying an invalid path does not produce an error. Consequently, you can include files that might not always be present. By default, the buildhistory class provides paths to the following files: BUILDHISTORY_IMAGE_FILES ?= "/etc/passwd /etc/group" BUILDHISTORY_PUSH_REPO BUILDHISTORY_PUSH_REPO[doc] = "When inheriting the buildhistory class, this variable optionally specifies a remote repository to which build history pushes Git changes." When inheriting the buildhistory class, this variable optionally specifies a remote repository to which build history pushes Git changes. In order for BUILDHISTORY_PUSH_REPO to work, BUILDHISTORY_COMMIT must be set to "1". The repository should correspond to a remote address that specifies a repository as understood by Git, or alternatively to a remote name that you have set up manually using git remote within the local repository. By default, the buildhistory class sets the variable as follows: BUILDHISTORY_PUSH_REPO ?= "" BUILDSDK_CFLAGS BUILDSDK_CFLAGS[doc] = "Specifies the flags to pass to the C compiler when building for the SDK." Specifies the flags to pass to the C compiler when building for the SDK. When building in the nativesdk- context, CFLAGS is set to the value of this variable by default. BUILDSDK_CPPFLAGS BUILDSDK_CPPFLAGS[doc] = "Specifies the flags to pass to the C pre-processor (i.e. to both the C and the C++ compilers) when building for the SDK." Specifies the flags to pass to the C pre-processor (i.e. to both the C and the C++ compilers) when building for the SDK. When building in the nativesdk- context, CPPFLAGS is set to the value of this variable by default. BUILDSDK_CXXFLAGS BUILDSDK_CXXFLAGS[doc] = "Specifies the flags to pass to the C++ compiler when building for the SDK." Specifies the flags to pass to the C++ compiler when building for the SDK. When building in the nativesdk- context, CXXFLAGS is set to the value of this variable by default. BUILDSDK_LDFLAGS BUILDSDK_LDFLAGS[doc] = "Specifies the flags to pass to the linker when building for the SDK." Specifies the flags to pass to the linker when building for the SDK. When building in the nativesdk- context, LDFLAGS is set to the value of this variable by default. BUILDSTATS_BASE BUILDSTATS_BASE[doc] = "Points to the location of the directory that holds build statistics when you use and enable the buildstats class." Points to the location of the directory that holds build statistics when you use and enable the buildstats class. The BUILDSTATS_BASE directory defaults to ${TMPDIR}/buildstats/. BUSYBOX_SPLIT_SUID BUSYBOX_SPLIT_SUID[doc] = "For the BusyBox recipe, specifies whether to split the output executable file into two parts: one for features that require setuid root, and one for the remaining features." For the BusyBox recipe, specifies whether to split the output executable file into two parts: one for features that require setuid root, and one for the remaining features (i.e. those that do not require setuid root). The BUSYBOX_SPLIT_SUID variable defaults to "1", which results in a single output executable file. Set the variable to "0" to split the output file. CACHE CACHE[doc] = "The directory BitBake uses to store a cache of the metadata." Specifies the directory BitBake uses to store a cache of the Metadata so it does not need to be parsed every time BitBake is started. CC CC[doc] = "Minimum command and arguments to run the C compiler." The minimal command and arguments used to run the C compiler. CFLAGS CFLAGS[doc] = "Flags passed to the C compiler for the target system. This variable evaluates to the same as TARGET_CFLAGS." Specifies the flags to pass to the C compiler. This variable is exported to an environment variable and thus made visible to the software being built during the compilation step. Default initialization for CFLAGS varies depending on what is being built: TARGET_CFLAGS when building for the target BUILD_CFLAGS when building for the build host (i.e. -native) BUILDSDK_CFLAGS when building for an SDK (i.e. nativesdk-) CLASSOVERRIDE CLASSOVERRIDE[doc] = "An internal variable specifying the special class override that should currently apply (e.g. "class-target", "class-native", and so forth)." An internal variable specifying the special class override that should currently apply (e.g. "class-target", "class-native", and so forth). The classes that use this variable (e.g. native, nativesdk, and so forth) set the variable to appropriate values. CLASSOVERRIDE gets its default "class-target" value from the bitbake.conf file. As an example, the following override allows you to install extra files, but only when building for the target: do_install_append_class-target() { install my-extra-file ${D}${sysconfdir} } Here is an example where FOO is set to "native" when building for the build host, and to "other" when not building for the build host: FOO_class-native = "native" FOO = "other" The underlying mechanism behind CLASSOVERRIDE is simply that it is included in the default value of OVERRIDES. CLEANBROKEN CLEANBROKEN[doc] = "Prevents the build system from running 'make clean' during the do_configure task." If set to "1" within a recipe, CLEANBROKEN specifies that the make clean command does not work for the software being built. Consequently, the OpenEmbedded build system will not try to run make clean during the do_configure task, which is the default behavior. COMBINED_FEATURES COMBINED_FEATURES[doc] = "A set of features common between MACHINE_FEATURES and DISTRO_FEATURES." Provides a list of hardware features that are enabled in both MACHINE_FEATURES and DISTRO_FEATURES. This select list of features contains features that make sense to be controlled both at the machine and distribution configuration level. For example, the "bluetooth" feature requires hardware support but should also be optional at the distribution level, in case the hardware supports Bluetooth but you do not ever intend to use it. For more information, see the MACHINE_FEATURES and DISTRO_FEATURES variables. COMMON_LICENSE_DIR COMMON_LICENSE_DIR[doc] = "Points to meta/files/common-licenses in the Source Directory, which is where generic license files reside." Points to meta/files/common-licenses in the Source Directory, which is where generic license files reside. COMPATIBLE_HOST COMPATIBLE_HOST[doc] = "A regular expression that resolves to one or more hosts (when the recipe is native) or one or more targets (when the recipe is non-native) with which a recipe is compatible." A regular expression that resolves to one or more hosts (when the recipe is native) or one or more targets (when the recipe is non-native) with which a recipe is compatible. The regular expression is matched against HOST_SYS. You can use the variable to stop recipes from being built for classes of systems with which the recipes are not compatible. Stopping these builds is particularly useful with kernels. The variable also helps to increase parsing speed since the build system skips parsing recipes not compatible with the current system. COMPATIBLE_MACHINE COMPATIBLE_MACHINE[doc] = "A regular expression that resolves to one or more target machines with which a recipe is compatible." A regular expression that resolves to one or more target machines with which a recipe is compatible. The regular expression is matched against MACHINEOVERRIDES. You can use the variable to stop recipes from being built for machines with which the recipes are not compatible. Stopping these builds is particularly useful with kernels. The variable also helps to increase parsing speed since the build system skips parsing recipes not compatible with the current machine. COMPLEMENTARY_GLOB COMPLEMENTARY_GLOB[doc] = "Defines wildcards to match when installing a list of complementary packages for all the packages installed in an image." Defines wildcards to match when installing a list of complementary packages for all the packages explicitly (or implicitly) installed in an image. The resulting list of complementary packages is associated with an item that can be added to IMAGE_FEATURES. An example usage of this is the "dev-pkgs" item that when added to IMAGE_FEATURES will install -dev packages (containing headers and other development files) for every package in the image. To add a new feature item pointing to a wildcard, use a variable flag to specify the feature item name and use the value to specify the wildcard. Here is an example: COMPLEMENTARY_GLOB[dev-pkgs] = '*-dev' CONF_VERSION CONF_VERSION[doc] = "Tracks the version of local.conf. Increased each time build/conf/ changes incompatibly." Tracks the version of the local configuration file (i.e. local.conf). The value for CONF_VERSION increments each time build/conf/ compatibility changes. CONFFILES CONFFILES[doc] = "Identifies editable or configurable files that are part of a package." Identifies editable or configurable files that are part of a package. If the Package Management System (PMS) is being used to update packages on the target system, it is possible that configuration files you have changed after the original installation and that you now want to remain unchanged are overwritten. In other words, editable files might exist in the package that you do not want reset as part of the package update process. You can use the CONFFILES variable to list the files in the package that you wish to prevent the PMS from overwriting during this update process. To use the CONFFILES variable, provide a package name override that identifies the resulting package. Then, provide a space-separated list of files. Here is an example: CONFFILES_${PN} += "${sysconfdir}/file1 \ ${sysconfdir}/file2 ${sysconfdir}/file3" A relationship exists between the CONFFILES and FILES variables. The files listed within CONFFILES must be a subset of the files listed within FILES. Because the configuration files you provide with CONFFILES are simply being identified so that the PMS will not overwrite them, it makes sense that the files must already be included as part of the package through the FILES variable. When specifying paths as part of the CONFFILES variable, it is good practice to use appropriate path variables. For example, ${sysconfdir} rather than /etc or ${bindir} rather than /usr/bin. You can find a list of these variables at the top of the meta/conf/bitbake.conf file in the Source Directory. CONFIG_INITRAMFS_SOURCE CONFIG_INITRAMFS_SOURCE[doc] = "Identifies the initial RAM filesystem (initramfs) source files. The OpenEmbedded build system receives and uses this kernel Kconfig variable as an environment variable." Identifies the initial RAM filesystem (initramfs) source files. The OpenEmbedded build system receives and uses this kernel Kconfig variable as an environment variable. By default, the variable is set to null (""). The CONFIG_INITRAMFS_SOURCE can be either a single cpio archive with a .cpio suffix or a space-separated list of directories and files for building the initramfs image. A cpio archive should contain a filesystem archive to be used as an initramfs image. Directories should contain a filesystem layout to be included in the initramfs image. Files should contain entries according to the format described by the usr/gen_init_cpio program in the kernel tree. If you specify multiple directories and files, the initramfs image will be the aggregate of all of them. For information on creating an initramfs, see the "Building an Initial RAM Filesystem (initramfs) Image" section in the Yocto Project Development Manual. CONFIG_SITE CONFIG_SITE[doc] = "A list of files that contains autoconf test results relevant to the current build. This variable is used by the Autotools utilities when running configure." A list of files that contains autoconf test results relevant to the current build. This variable is used by the Autotools utilities when running configure. CONFIGURE_FLAGS CONFIGURE_FLAGS[doc] = "The minimal arguments for GNU configure." The minimal arguments for GNU configure. CONFLICT_DISTRO_FEATURES CONFLICT_DISTRO_FEATURES[doc] = "When a recipe inherits the distro_features_check class, this variable identifies distribution features that would be in conflict should the recipe be built." When inheriting the distro_features_check class, this variable identifies distribution features that would be in conflict should the recipe be built. In other words, if the CONFLICT_DISTRO_FEATURES variable lists a feature that also appears in DISTRO_FEATURES within the current configuration, an error occurs and the build stops. COPYLEFT_LICENSE_EXCLUDE COPYLEFT_LICENSE_EXCLUDE[doc] = "Licenses to exclude in the source archived by the archiver class." A space-separated list of licenses to exclude from the source archived by the archiver class. In other words, if a license in a recipe's LICENSE value is in the value of COPYLEFT_LICENSE_EXCLUDE, then its source is not archived by the class. The COPYLEFT_LICENSE_EXCLUDE variable takes precedence over the COPYLEFT_LICENSE_INCLUDE variable. The default value, which is "CLOSED Proprietary", for COPYLEFT_LICENSE_EXCLUDE is set by the copyleft_filter class, which is inherited by the archiver class. COPYLEFT_LICENSE_INCLUDE COPYLEFT_LICENSE_INCLUDE[doc] = "Licenses to include in the source archived by the archiver class." A space-separated list of licenses to include in the source archived by the archiver class. In other words, if a license in a recipe's LICENSE value is in the value of COPYLEFT_LICENSE_INCLUDE, then its source is archived by the class. The default value is set by the copyleft_filter class, which is inherited by the archiver class. The default value includes "GPL*", "LGPL*", and "AGPL*". COPYLEFT_PN_EXCLUDE COPYLEFT_PN_EXCLUDE[doc] = "Recipes to exclude in the source archived by the archiver class." A list of recipes to exclude in the source archived by the archiver class. The COPYLEFT_PN_EXCLUDE variable overrides the license inclusion and exclusion caused through the COPYLEFT_LICENSE_INCLUDE and COPYLEFT_LICENSE_EXCLUDE variables, respectively. The default value, which is "" indicating to not explicitly exclude any recipes by name, for COPYLEFT_PN_EXCLUDE is set by the copyleft_filter class, which is inherited by the archiver class. COPYLEFT_PN_INCLUDE COPYLEFT_PN_INCLUDE[doc] = "Recipes to include in the source archived by the archiver class." A list of recipes to include in the source archived by the archiver class. The COPYLEFT_PN_INCLUDE variable overrides the license inclusion and exclusion caused through the COPYLEFT_LICENSE_INCLUDE and COPYLEFT_LICENSE_EXCLUDE variables, respectively. The default value, which is "" indicating to not explicitly include any recipes by name, for COPYLEFT_PN_INCLUDE is set by the copyleft_filter class, which is inherited by the archiver class. COPYLEFT_RECIPE_TYPES COPYLEFT_RECIPE_TYPES[doc] = "Recipe types to include in the source archived by the archiver class." A space-separated list of recipe types to include in the source archived by the archiver class. Recipe types are target, native, nativesdk, cross, crosssdk, and cross-canadian. The default value, which is "target*", for COPYLEFT_RECIPE_TYPES is set by the copyleft_filter class, which is inherited by the archiver class. COPY_LIC_DIRS COPY_LIC_DIRS[doc] = "If set to "1" along with the COPY_LIC_MANIFEST variable, the OpenEmbedded build system copies into the image the license files, which are located in /usr/share/common-licenses, for each package." If set to "1" along with the COPY_LIC_MANIFEST variable, the OpenEmbedded build system copies into the image the license files, which are located in /usr/share/common-licenses, for each package. The license files are placed in directories within the image itself during build time. The COPY_LIC_DIRS does not offer a path for adding licenses for newly installed packages to an image, which might be most suitable for read-only filesystems that cannot be upgraded. See the LICENSE_CREATE_PACKAGE variable for additional information. You can also reference the "Providing License Text" section in the Yocto Project Development Manual for information on providing license text. COPY_LIC_MANIFEST COPY_LIC_MANIFEST[doc] = "If set to "1", the OpenEmbedded build system copies the license manifest for the image to /usr/share/common-licenses/license.manifest within the image itself." If set to "1", the OpenEmbedded build system copies the license manifest for the image to /usr/share/common-licenses/license.manifest within the image itself during build time. The COPY_LIC_MANIFEST does not offer a path for adding licenses for newly installed packages to an image, which might be most suitable for read-only filesystems that cannot be upgraded. See the LICENSE_CREATE_PACKAGE variable for additional information. You can also reference the "Providing License Text" section in the Yocto Project Development Manual for information on providing license text. CORE_IMAGE_EXTRA_INSTALL CORE_IMAGE_EXTRA_INSTALL[doc] = "Specifies the list of packages to be added to the image. You should only set this variable in the conf/local.conf file in the Build Directory." Specifies the list of packages to be added to the image. You should only set this variable in the local.conf configuration file found in the Build Directory. This variable replaces POKY_EXTRA_INSTALL, which is no longer supported. COREBASE COREBASE[doc] = "Specifies the parent directory of the OpenEmbedded Core Metadata layer (i.e. meta)." Specifies the parent directory of the OpenEmbedded Core Metadata layer (i.e. meta). It is an important distinction that COREBASE points to the parent of this layer and not the layer itself. Consider an example where you have cloned the Poky Git repository and retained the poky name for your local copy of the repository. In this case, COREBASE points to the poky folder because it is the parent directory of the poky/meta layer. COREBASE_FILES COREBASE_FILES[doc] = "Lists files from the COREBASE directory that should be copied other than the layers listed in the bblayers.conf file." Lists files from the COREBASE directory that should be copied other than the layers listed in the bblayers.conf file. The COREBASE_FILES variable exists for the purpose of copying metadata from the OpenEmbedded build system into the extensible SDK. Explicitly listing files in COREBASE is needed because it typically contains build directories and other files that should not normally be copied into the extensible SDK. Consequently, the value of COREBASE_FILES is used in order to only copy the files that are actually needed. CPP CPP[doc] = "Minimum command and arguments to run the C preprocessor." The minimal command and arguments used to run the C preprocessor. CPPFLAGS CPPFLAGS[doc] = "Specifies the flags to pass to the C pre-processor (i.e. to both the C and the C++ compilers)." Specifies the flags to pass to the C pre-processor (i.e. to both the C and the C++ compilers). This variable is exported to an environment variable and thus made visible to the software being built during the compilation step. Default initialization for CPPFLAGS varies depending on what is being built: TARGET_CPPFLAGS when building for the target BUILD_CPPFLAGS when building for the build host (i.e. -native) BUILDSDK_CPPFLAGS when building for an SDK (i.e. nativesdk-) CROSS_COMPILE CROSS_COMPILE[doc] = "The toolchain binary prefix for the target tools." The toolchain binary prefix for the target tools. The CROSS_COMPILE variable is the same as the TARGET_PREFIX variable. The OpenEmbedded build system sets the CROSS_COMPILE variable only in certain contexts (e.g. when building for kernel and kernel module recipes). CVSDIR CVSDIR[doc] = "The directory where cvs checkouts will be stored in." The directory in which files checked out under the CVS system are stored. CXX CXX[doc] = "Minimum command and arguments to run the C++ compiler." The minimal command and arguments used to run the C++ compiler. CXXFLAGS CXXFLAGS[doc] = "Specifies the flags to pass to the C++ compiler." Specifies the flags to pass to the C++ compiler. This variable is exported to an environment variable and thus made visible to the software being built during the compilation step. Default initialization for CXXFLAGS varies depending on what is being built: TARGET_CXXFLAGS when building for the target BUILD_CXXFLAGS when building for the build host (i.e. -native) BUILDSDK_CXXFLAGS when building for an SDK (i.e. nativesdk-) D D[doc] = "The destination directory." The destination directory. The location in the Build Directory where components are installed by the do_install task. This location defaults to: ${WORKDIR}/image Tasks that read from or write to this directory should run under fakeroot. DATE DATE[doc] = "The date the build was started using YMD format." The date the build was started. Dates appear using the year, month, and day (YMD) format (e.g. "20150209" for February 9th, 2015). DATETIME DATETIME[doc] = "The date and time the build was started." The date and time on which the current build started. The format is suitable for timestamps. DEBIAN_NOAUTONAME DEBIAN_NOAUTONAME[doc] = "Prevents a particular package from being renamed according to Debian package naming." When the debian class is inherited, which is the default behavior, DEBIAN_NOAUTONAME specifies a particular package should not be renamed according to Debian library package naming. You must use the package name as an override when you set this variable. Here is an example from the fontconfig recipe: DEBIAN_NOAUTONAME_fontconfig-utils = "1" DEBIANNAME DEBIANNAME[doc] = "Allows you to override the library name for an individual package for Debian library package renaming." When the debian class is inherited, which is the default behavior, DEBIANNAME allows you to override the library name for an individual package. Overriding the library name in these cases is rare. You must use the package name as an override when you set this variable. Here is an example from the dbus recipe: DEBIANNAME_${PN} = "dbus-1" DEBUG_BUILD DEBUG_BUILD[doc] = "Specifies to build packages with debugging information. This influences the value of the SELECTED_OPTIMIZATION variable." Specifies to build packages with debugging information. This influences the value of the SELECTED_OPTIMIZATION variable. DEBUG_OPTIMIZATION DEBUG_OPTIMIZATION[doc] = "The options to pass in TARGET_CFLAGS and CFLAGS when compiling a system for debugging. This variable defaults to '-O -fno-omit-frame-pointer -g'." The options to pass in TARGET_CFLAGS and CFLAGS when compiling a system for debugging. This variable defaults to "-O -fno-omit-frame-pointer ${DEBUG_FLAGS} -pipe". DEFAULT_PREFERENCE DEFAULT_PREFERENCE[doc] = "Specifies a weak bias for recipe selection priority." Specifies a weak bias for recipe selection priority. The most common usage of this is variable is to set it to "-1" within a recipe for a development version of a piece of software. Using the variable in this way causes the stable version of the recipe to build by default in the absence of PREFERRED_VERSION being used to build the development version. The bias provided by DEFAULT_PREFERENCE is weak and is overridden by BBFILE_PRIORITY if that variable is different between two layers that contain different versions of the same recipe. DEFAULTTUNE DEFAULTTUNE[doc] = "The default CPU and Application Binary Interface (ABI) tunings (i.e. the "tune") used by the OpenEmbedded build system." The default CPU and Application Binary Interface (ABI) tunings (i.e. the "tune") used by the OpenEmbedded build system. The DEFAULTTUNE helps define TUNE_FEATURES. The default tune is either implicitly or explicitly set by the machine (MACHINE). However, you can override the setting using available tunes as defined with AVAILTUNES. DEPENDS DEPENDS[doc] = "Lists a recipe's build-time dependencies (i.e. other recipe files)." Lists a recipe's build-time dependencies. These are dependencies on other recipes whose contents (e.g. headers and shared libraries) are needed by the recipe at build time. As an example, consider a recipe foo that contains the following assignment: DEPENDS = "bar" The practical effect of the previous assignment is that all files installed by bar will be available in the appropriate staging sysroot, given by the STAGING_DIR* variables, by the time the do_configure task for foo runs. This mechanism is implemented by having do_configure depend on the do_populate_sysroot task of each recipe listed in DEPENDS, through a [deptask] declaration in the base class. It seldom is necessary to reference, for example, STAGING_DIR_HOST explicitly. The standard classes and build-related variables are configured to automatically use the appropriate staging sysroots. As another example, DEPENDS can also be used to add utilities that run on the build machine during the build. For example, a recipe that makes use of a code generator built by the recipe codegen might have the following: DEPENDS = "codegen-native" For more information, see the native class and the EXTRANATIVEPATH variable. DEPENDS is a list of recipe names. Or, to be more precise, it is a list of PROVIDES names, which usually match recipe names. Putting a package name such as "foo-dev" in DEPENDS does not make sense. Use "foo" instead, as this will put files from all the packages that make up foo, which includes those from foo-dev, into the sysroot. One recipe having another recipe in DEPENDS does not by itself add any runtime dependencies between the packages produced by the two recipes. However, as explained in the "Automatically Added Runtime Dependencies" section, runtime dependencies will often be added automatically, meaning DEPENDS alone is sufficient for most recipes. Counterintuitively, DEPENDS is often necessary even for recipes that install precompiled components. For example, if libfoo is a precompiled library that links against libbar, then linking against libfoo requires both libfoo and libbar to be available in the sysroot. Without a DEPENDS from the recipe that installs libfoo to the recipe that installs libbar, other recipes might fail to link against libfoo. For information on runtime dependencies, see the RDEPENDS variable. You can also see the "Tasks" and "Dependencies" sections in the BitBake User Manual for additional information on tasks and dependencies. DEPLOY_DIR DEPLOY_DIR[doc] = "Points to the general area that the OpenEmbedded build system uses to place images, packages, SDKs and other output files that are ready to be used outside of the build system." Points to the general area that the OpenEmbedded build system uses to place images, packages, SDKs and other output files that are ready to be used outside of the build system. By default, this directory resides within the Build Directory as ${TMPDIR}/deploy. For more information on the structure of the Build Directory, see "The Build Directory - build/" section. For more detail on the contents of the deploy directory, see the "Images", "Package Feeds", and "Application Development SDK" sections. DEPLOY_DIR_DEB DEPLOY_DIR_DEB[doc] = "Points to a Debian-specific area that the OpenEmbedded build system uses to place images, packages, SDKs and other output files that are ready to be used outside of the build system." Points to the area that the OpenEmbedded build system uses to place Debian packages that are ready to be used outside of the build system. This variable applies only when PACKAGE_CLASSES contains "package_deb". The BitBake configuration file initially defines the DEPLOY_DIR_DEB variable as a sub-folder of DEPLOY_DIR: DEPLOY_DIR_DEB = "${DEPLOY_DIR}/deb" The package_deb class uses the DEPLOY_DIR_DEB variable to make sure the do_package_write_deb task writes Debian packages into the appropriate folder. For more information on how packaging works, see the "Package Feeds" section. DEPLOY_DIR_IMAGE DEPLOY_DIR_IMAGE[doc] = "Points to the area that the OpenEmbedded build system uses to place images and other associated output files that are ready to be deployed onto the target machine." Points to the area that the OpenEmbedded build system uses to place images and other associated output files that are ready to be deployed onto the target machine. The directory is machine-specific as it contains the ${MACHINE} name. By default, this directory resides within the Build Directory as ${DEPLOY_DIR}/images/${MACHINE}/. For more information on the structure of the Build Directory, see "The Build Directory - build/" section. For more detail on the contents of the deploy directory, see the "Images" and "Application Development SDK" sections. DEPLOY_DIR_IPK DEPLOY_DIR_IPK[doc] = "Points to a IPK-specific area that the OpenEmbedded build system uses to place images, packages, SDKs and other output files that are ready to be used outside of the build system." Points to the area that the OpenEmbedded build system uses to place IPK packages that are ready to be used outside of the build system. This variable applies only when PACKAGE_CLASSES contains "package_ipk". The BitBake configuration file initially defines this variable as a sub-folder of DEPLOY_DIR: DEPLOY_DIR_IPK = "${DEPLOY_DIR}/ipk" The package_ipk class uses the DEPLOY_DIR_IPK variable to make sure the do_package_write_ipk task writes IPK packages into the appropriate folder. For more information on how packaging works, see the "Package Feeds" section. DEPLOY_DIR_RPM DEPLOY_DIR_RPM[doc] = "Points to a RPM-specific area that the OpenEmbedded build system uses to place images, packages, SDKs and other output files that are ready to be used outside of the build system." Points to the area that the OpenEmbedded build system uses to place RPM packages that are ready to be used outside of the build system. This variable applies only when PACKAGE_CLASSES contains "package_rpm". The BitBake configuration file initially defines this variable as a sub-folder of DEPLOY_DIR: DEPLOY_DIR_RPM = "${DEPLOY_DIR}/rpm" The package_rpm class uses the DEPLOY_DIR_RPM variable to make sure the do_package_write_rpm task writes RPM packages into the appropriate folder. For more information on how packaging works, see the "Package Feeds" section. DEPLOY_DIR_TAR DEPLOY_DIR_TAR[doc] = "Points to a tarball area that the OpenEmbedded build system uses to place images, packages, SDKs and other output files that are ready to be used outside of the build system." Points to the area that the OpenEmbedded build system uses to place tarballs that are ready to be used outside of the build system. This variable applies only when PACKAGE_CLASSES contains "package_tar". The BitBake configuration file initially defines this variable as a sub-folder of DEPLOY_DIR: DEPLOY_DIR_TAR = "${DEPLOY_DIR}/tar" The package_tar class uses the DEPLOY_DIR_TAR variable to make sure the do_package_write_tar task writes TAR packages into the appropriate folder. For more information on how packaging works, see the "Package Feeds" section. DEPLOYDIR DEPLOYDIR[doc] = "For recipes that inherit the deploy class, the DEPLOYDIR points to a temporary work area for deployed files." When inheriting the deploy class, the DEPLOYDIR points to a temporary work area for deployed files that is set in the deploy class as follows: DEPLOYDIR = "${WORKDIR}/deploy-${PN}" Recipes inheriting the deploy class should copy files to be deployed into DEPLOYDIR, and the class will take care of copying them into DEPLOY_DIR_IMAGE afterwards. DESCRIPTION DESCRIPTION[doc] = "The package description used by package managers. If not set, DESCRIPTION takes the value of the SUMMARY variable." The package description used by package managers. If not set, DESCRIPTION takes the value of the SUMMARY variable. DISK_SIGNATURE DISK_SIGNATURE[doc] = "A 32-bit MBR disk signature used by directdisk images." A 32-bit MBR disk signature used by directdisk images. By default, the signature is set to an automatically generated random value that allows the OpenEmbedded build system to create a boot loader. You can override the signature in the image recipe by setting DISK_SIGNATURE to an 8-digit hex string. You might want to override DISK_SIGNATURE if you want the disk signature to remain constant between image builds. When using Linux 3.8 or later, you can use DISK_SIGNATURE to specify the root by UUID to allow the kernel to locate the root device even if the device name changes due to differences in hardware configuration. By default, ROOT_VM is set as follows: ROOT_VM ?= "root=/dev/sda2" However, you can change this to locate the root device using the disk signature instead: ROOT_VM = "root=PARTUUID=${DISK_SIGNATURE}-02" As previously mentioned, it is possible to set the DISK_SIGNATURE variable in your local.conf file to a fixed value if you do not want syslinux.cfg changing for each build. You might find this useful when you want to upgrade the root filesystem on a device without having to recreate or modify the master boot record. DISTRO DISTRO[doc] = "The short name of the distribution. If the variable is blank, meta/conf/distro/defaultsetup.conf will be used." The short name of the distribution. This variable corresponds to a distribution configuration file whose root name is the same as the variable's argument and whose filename extension is .conf. For example, the distribution configuration file for the Poky distribution is named poky.conf and resides in the meta-poky/conf/distro directory of the Source Directory. Within that poky.conf file, the DISTRO variable is set as follows: DISTRO = "poky" Distribution configuration files are located in a conf/distro directory within the Metadata that contains the distribution configuration. The value for DISTRO must not contain spaces, and is typically all lower-case. If the DISTRO variable is blank, a set of default configurations are used, which are specified within meta/conf/distro/defaultsetup.conf also in the Source Directory. DISTRO_CODENAME DISTRO_CODENAME[doc] = "Specifies a codename for the distribution being built." Specifies a codename for the distribution being built. DISTRO_EXTRA_RDEPENDS DISTRO_EXTRA_RDEPENDS[doc] = "Specifies a list of distro-specific packages to add to all images. The variable only applies to the images that include packagegroup-base." Specifies a list of distro-specific packages to add to all images. This variable takes affect through packagegroup-base so the variable only really applies to the more full-featured images that include packagegroup-base. You can use this variable to keep distro policy out of generic images. As with all other distro variables, you set this variable in the distro .conf file. DISTRO_EXTRA_RRECOMMENDS DISTRO_EXTRA_RRECOMMENDS[doc] = "Specifies a list of distro-specific packages to add to all images if the packages exist. The list of packages are automatically installed but you can remove them." Specifies a list of distro-specific packages to add to all images if the packages exist. The packages might not exist or be empty (e.g. kernel modules). The list of packages are automatically installed but you can remove them. DISTRO_FEATURES DISTRO_FEATURES[doc] = "The features enabled for the distribution." The software support you want in your distribution for various features. You define your distribution features in the distribution configuration file. In most cases, the presence or absence of a feature in DISTRO_FEATURES is translated to the appropriate option supplied to the configure script during the do_configure task for recipes that optionally support the feature. For example, specifying "x11" in DISTRO_FEATURES, causes every piece of software built for the target that can optionally support X11 to have its X11 support enabled. Two more examples are Bluetooth and NFS support. For a more complete list of features that ships with the Yocto Project and that you can provide with this variable, see the "Distro Features" section. DISTRO_FEATURES_BACKFILL DISTRO_FEATURES_BACKFILL[doc] = "Features to be added to DISTRO_FEATURES if not also present in DISTRO_FEATURES_BACKFILL_CONSIDERED. This variable is set in the meta/conf/bitbake.conf file and it is not intended to be user-configurable." Features to be added to DISTRO_FEATURES if not also present in DISTRO_FEATURES_BACKFILL_CONSIDERED. This variable is set in the meta/conf/bitbake.conf file. It is not intended to be user-configurable. It is best to just reference the variable to see which distro features are being backfilled for all distro configurations. See the Feature backfilling section for more information. DISTRO_FEATURES_BACKFILL_CONSIDERED DISTRO_FEATURES_BACKFILL_CONSIDERED[doc] = "Features from DISTRO_FEATURES_BACKFILL that should not be backfilled (i.e. added to DISTRO_FEATURES) during the build." Features from DISTRO_FEATURES_BACKFILL that should not be backfilled (i.e. added to DISTRO_FEATURES) during the build. See the "Feature Backfilling" section for more information. DISTRO_FEATURES_DEFAULT DISTRO_FEATURES_DEFAULT[doc] = "Provides the default list of distro features with the exception of any libc-specific features." A convenience variable that gives you the default list of distro features with the exception of any features specific to the C library (libc). When creating a custom distribution, you might find it useful to be able to reuse the default DISTRO_FEATURES options without the need to write out the full set. Here is an example that uses DISTRO_FEATURES_DEFAULT from a custom distro configuration file: DISTRO_FEATURES ?= "${DISTRO_FEATURES_DEFAULT} ${DISTRO_FEATURES_LIBC} myfeature" DISTRO_FEATURES_FILTER_NATIVE DISTRO_FEATURES_FILTER_NATIVE[doc] = "Specifies a list of features that if present in the target DISTRO_FEATURES value should be included in DISTRO_FEATURES when building native recipes." Specifies a list of features that if present in the target DISTRO_FEATURES value should be included in DISTRO_FEATURES when building native recipes. This variable is used in addition to the features filtered using the DISTRO_FEATURES_NATIVE variable. DISTRO_FEATURES_FILTER_NATIVESDK DISTRO_FEATURES_FILTER_NATIVESDK[doc] = "Specifies a list of features that if present in the target DISTRO_FEATURES value should be included in DISTRO_FEATURES when building nativesdk recipes." Specifies a list of features that if present in the target DISTRO_FEATURES value should be included in DISTRO_FEATURES when building nativesdk recipes. This variable is used in addition to the features filtered using the DISTRO_FEATURES_NATIVESDK variable. DISTRO_FEATURES_LIBC DISTRO_FEATURES_LIBC[doc] = "Specifies the list of distro features that are specific to the C library (libc)." A convenience variable that specifies the list of distro features that are specific to the C library (libc). Typically, these features are prefixed with "libc-" and control which features are enabled at during the build within the C library itself. DISTRO_FEATURES_NATIVE DISTRO_FEATURES_NATIVE[doc] = "Specifies a list of features that should be included in DISTRO_FEATURES when building native recipes." Specifies a list of features that should be included in DISTRO_FEATURES when building native recipes. This variable is used in addition to the features filtered using the DISTRO_FEATURES_FILTER_NATIVE variable. DISTRO_FEATURES_NATIVESDK DISTRO_FEATURES_NATIVESDK[doc] = "Specifies a list of features that should be included in DISTRO_FEATURES when building nativesdk recipes." Specifies a list of features that should be included in DISTRO_FEATURES when building nativesdk recipes. This variable is used in addition to the features filtered using the DISTRO_FEATURES_FILTER_NATIVESDK variable. DISTRO_NAME DISTRO_NAME[doc] = "The long name of the distribution." The long name of the distribution. DISTRO_VERSION DISTRO_VERSION[doc] = "The version of the distribution." The version of the distribution. DISTROOVERRIDES DISTROOVERRIDES[doc] = "A colon-separated list of overrides specific to the current distribution." A colon-separated list of overrides specific to the current distribution. By default, this list includes the value of DISTRO. You can extend DISTROOVERRIDES to add extra overrides that should apply to the distribution. The underlying mechanism behind DISTROOVERRIDES is simply that it is included in the default value of OVERRIDES. DL_DIR DL_DIR[doc] = "The central download directory used by the build process to store downloads. By default, the directory is 'downloads' in the Build Directory." The central download directory used by the build process to store downloads. By default, DL_DIR gets files suitable for mirroring for everything except Git repositories. If you want tarballs of Git repositories, use the BB_GENERATE_MIRROR_TARBALLS variable. You can set this directory by defining the DL_DIR variable in the conf/local.conf file. This directory is self-maintaining and you should not have to touch it. By default, the directory is downloads in the Build Directory. #DL_DIR ?= "${TOPDIR}/downloads" To specify a different download directory, simply remove the comment from the line and provide your directory. During a first build, the system downloads many different source code tarballs from various upstream projects. Downloading can take a while, particularly if your network connection is slow. Tarballs are all stored in the directory defined by DL_DIR and the build system looks there first to find source tarballs. When wiping and rebuilding, you can preserve this directory to speed up this part of subsequent builds. You can safely share this directory between multiple builds on the same development machine. For additional information on how the build process gets source files when working behind a firewall or proxy server, see this specific question in the "FAQ" chapter. You can also refer to the "Working Behind a Network Proxy" Wiki page. DOC_COMPRESS DOC_COMPRESS[doc] = "When inheriting the compress_doc class, this variable sets the compression policy used when the OpenEmbedded build system compresses man pages and info pages." When inheriting the compress_doc class, this variable sets the compression policy used when the OpenEmbedded build system compresses man pages and info pages. By default, the compression method used is gz (gzip). Other policies available are xz and bz2. For information on policies and on how to use this variable, see the comments in the meta/classes/compress_doc.bbclass file. EFI_PROVIDER EFI_PROVIDER[doc] = "When building bootable images (i.e. where hddimg or vmdk is in IMAGE_FSTYPES), the EFI_PROVIDER variable specifies the EFI bootloader to use." When building bootable images (i.e. where hddimg or vmdk is in IMAGE_FSTYPES), the EFI_PROVIDER variable specifies the EFI bootloader to use. The default is "grub-efi", but "systemd-boot" can be used instead. See the systemd-boot and image-live classes for more information. ENABLE_BINARY_LOCALE_GENERATION ENABLE_BINARY_LOCALE_GENERATION[doc] = "Controls which locales for glibc are generated during the build. The variable is useful if the target device has 64Mbytes of RAM or less." Variable that controls which locales for glibc are generated during the build (useful if the target device has 64Mbytes of RAM or less). ERR_REPORT_DIR ERR_REPORT_DIR[doc] = "When used with the report-error class, specifies the path used for storing the debug files created by the error reporting tool, which allows you to submit build errors you encounter to a central database." When used with the report-error class, specifies the path used for storing the debug files created by the error reporting tool, which allows you to submit build errors you encounter to a central database. By default, the value of this variable is ${LOG_DIR}/error-report. You can set ERR_REPORT_DIR to the path you want the error reporting tool to store the debug files as follows in your local.conf file: ERR_REPORT_DIR = "path" ERROR_QA ERROR_QA[doc] = "Specifies the quality assurance checks whose failures are reported as errors by the OpenEmbedded build system." Specifies the quality assurance checks whose failures are reported as errors by the OpenEmbedded build system. You set this variable in your distribution configuration file. For a list of the checks you can control with this variable, see the "insane.bbclass" section. EXCLUDE_FROM_SHLIBS EXCLUDE_FROM_SHLIBS[doc] = "Causes the OpenEmbedded build system's shared libraries resolver to exclude an entire package when scanning for shared libraries." Triggers the OpenEmbedded build system's shared libraries resolver to exclude an entire package when scanning for shared libraries. The shared libraries resolver's functionality results in part from the internal function package_do_shlibs, which is part of the do_package task. You should be aware that the shared libraries resolver might implicitly define some dependencies between packages. The EXCLUDE_FROM_SHLIBS variable is similar to the PRIVATE_LIBS variable, which excludes a package's particular libraries only and not the whole package. Use the EXCLUDE_FROM_SHLIBS variable by setting it to "1" for a particular package: EXCLUDE_FROM_SHLIBS = "1" EXCLUDE_FROM_WORLD EXCLUDE_FROM_WORLD[doc] = "Directs BitBake to exclude a recipe from world builds (i.e. bitbake world)." Directs BitBake to exclude a recipe from world builds (i.e. bitbake world). During world builds, BitBake locates, parses and builds all recipes found in every layer exposed in the bblayers.conf configuration file. To exclude a recipe from a world build using this variable, set the variable to "1" in the recipe. Recipes added to EXCLUDE_FROM_WORLD may still be built during a world build in order to satisfy dependencies of other recipes. Adding a recipe to EXCLUDE_FROM_WORLD only ensures that the recipe is not explicitly added to the list of build targets in a world build. EXTENDPE EXTENDPE[doc] = "Used with file and pathnames to create a prefix for a recipe's version based on the recipe's PE value. If PE is set and greater than zero for a recipe, EXTENDPE becomes that value." Used with file and pathnames to create a prefix for a recipe's version based on the recipe's PE value. If PE is set and greater than zero for a recipe, EXTENDPE becomes that value (e.g if PE is equal to "1" then EXTENDPE becomes "1_"). If a recipe's PE is not set (the default) or is equal to zero, EXTENDPE becomes "". See the STAMP variable for an example. EXTENDPKGV EXTENDPKGV[doc] = "The full package version specification as it appears on the final packages produced by a recipe." The full package version specification as it appears on the final packages produced by a recipe. The variable's value is normally used to fix a runtime dependency to the exact same version of another package in the same recipe: RDEPENDS_${PN}-additional-module = "${PN} (= ${EXTENDPKGV})" The dependency relationships are intended to force the package manager to upgrade these types of packages in lock-step. EXTERNAL_KERNEL_TOOLS EXTERNAL_KERNEL_TOOLS[doc] = "Indicates kernel tools are external to the source tree." When set, the EXTERNAL_KERNEL_TOOLS variable indicates that these tools are not in the source tree. When kernel tools are available in the tree, they are preferred over any externally installed tools. Setting the EXTERNAL_KERNEL_TOOLS variable tells the OpenEmbedded build system to prefer the installed external tools. See the kernel-yocto class in meta/classes to see how the variable is used. EXTERNALSRC EXTERNALSRC[doc] = "If externalsrc.bbclass is inherited, this variable points to the source tree, which is outside of the OpenEmbedded build system." When inheriting the externalsrc class, this variable points to the source tree, which is outside of the OpenEmbedded build system. When set, this variable sets the S variable, which is what the OpenEmbedded build system uses to locate unpacked recipe source code. For more information on externalsrc.bbclass, see the "externalsrc.bbclass" section. You can also find information on how to use this variable in the "Building Software from an External Source" section in the Yocto Project Development Manual. EXTERNALSRC_BUILD EXTERNALSRC_BUILD[doc] = "If externalsrc.bbclass is inherited, this variable points to the directory in which the recipe's source code is built, which is outside of the OpenEmbedded build system." When inheriting the externalsrc class, this variable points to the directory in which the recipe's source code is built, which is outside of the OpenEmbedded build system. When set, this variable sets the B variable, which is what the OpenEmbedded build system uses to locate the Build Directory. For more information on externalsrc.bbclass, see the "externalsrc.bbclass" section. You can also find information on how to use this variable in the "Building Software from an External Source" section in the Yocto Project Development Manual. EXTRA_AUTORECONF EXTRA_AUTORECONF[doc] = "Extra options passed to the autoreconf command, which is executed during do_configure." For recipes inheriting the autotools class, you can use EXTRA_AUTORECONF to specify extra options to pass to the autoreconf command that is executed during the do_configure task. The default value is "--exclude=autopoint". EXTRA_IMAGE_FEATURES EXTRA_IMAGE_FEATURES[doc] = "The list of additional features to include in an image. Configure this variable in the conf/local.conf file in the Build Directory." A list of additional features to include in an image. When listing more than one feature, separate them with a space. Typically, you configure this variable in your local.conf file, which is found in the Build Directory. Although you can use this variable from within a recipe, best practices dictate that you do not. To enable primary features from within the image recipe, use the IMAGE_FEATURES variable. Here are some examples of features you can add: "dbg-pkgs" - Adds -dbg packages for all installed packages including symbol information for debugging and profiling. "debug-tweaks" - Makes an image suitable for debugging. For example, allows root logins without passwords and enables post-installation logging. See the 'allow-empty-password' and 'post-install-logging' features in the "Image Features" section for more information. "dev-pkgs" - Adds -dev packages for all installed packages. This is useful if you want to develop against the libraries in the image. "read-only-rootfs" - Creates an image whose root filesystem is read-only. See the "Creating a Read-Only Root Filesystem" section in the Yocto Project Development Manual for more information "tools-debug" - Adds debugging tools such as gdb and strace. "tools-sdk" - Adds development tools such as gcc, make, pkgconfig and so forth. "tools-testapps" - Adds useful testing tools such as ts_print, aplay, arecord and so forth. For a complete list of image features that ships with the Yocto Project, see the "Image Features" section. For an example that shows how to customize your image by using this variable, see the "Customizing Images Using Custom IMAGE_FEATURES and EXTRA_IMAGE_FEATURES" section in the Yocto Project Development Manual. EXTRA_IMAGECMD EXTRA_IMAGECMD[doc] = "Specifies additional options for the image creation command that has been specified in IMAGE_CMD. When setting this variable, you should use an override for the associated type." Specifies additional options for the image creation command that has been specified in IMAGE_CMD. When setting this variable, you should use an override for the associated type. Here is an example: EXTRA_IMAGECMD_ext3 ?= "-i 4096" EXTRA_IMAGEDEPENDS EXTRA_IMAGEDEPENDS[doc] = "A list of recipes to build that do not provide packages for installing into the root filesystem. Use this variable to list recipes that are required to build the final image, but not needed in the root filesystem." A list of recipes to build that do not provide packages for installing into the root filesystem. Sometimes a recipe is required to build the final image but is not needed in the root filesystem. You can use the EXTRA_IMAGEDEPENDS variable to list these recipes and thus specify the dependencies. A typical example is a required bootloader in a machine configuration. To add packages to the root filesystem, see the various *RDEPENDS and *RRECOMMENDS variables. EXTRANATIVEPATH EXTRANATIVEPATH[doc] = "A list of subdirectories of ${STAGING_BINDIR_NATIVE} added to the beginning of the environment variable PATH." A list of subdirectories of ${STAGING_BINDIR_NATIVE} added to the beginning of the environment variable PATH. As an example, the following prepends "${STAGING_BINDIR_NATIVE}/foo:${STAGING_BINDIR_NATIVE}/bar:" to PATH: EXTRANATIVEPATH = "foo bar" EXTRA_OECMAKE EXTRA_OECMAKE[doc] = "Additional cmake options." Additional cmake options. EXTRA_OECONF EXTRA_OECONF[doc] = "Additional configure script options." Additional configure script options. See PACKAGECONFIG_CONFARGS for additional information on passing configure script options. EXTRA_OEMAKE EXTRA_OEMAKE[doc] = "Additional GNU make options." Additional GNU make options. Because the EXTRA_OEMAKE defaults to "", you need to set the variable to specify any required GNU options. PARALLEL_MAKE and PARALLEL_MAKEINST also make use of EXTRA_OEMAKE to pass the required flags. EXTRA_OESCONS EXTRA_OESCONS[doc] = "When a recipe inherits the scons class, this variable specifies additional configuration options you want to pass to the scons command line." When inheriting the scons class, this variable specifies additional configuration options you want to pass to the scons command line. EXTRA_USERS_PARAMS EXTRA_USERS_PARAMS[doc] = "When a recipe inherits the extrausers class, this variable provides image level user and group operations." When inheriting the extrausers class, this variable provides image level user and group operations. This is a more global method of providing user and group configuration as compared to using the useradd class, which ties user and group configurations to a specific recipe. The set list of commands you can configure using the EXTRA_USERS_PARAMS is shown in the extrausers class. These commands map to the normal Unix commands of the same names: # EXTRA_USERS_PARAMS = "\ # useradd -p '' tester; \ # groupadd developers; \ # userdel nobody; \ # groupdel -g video; \ # groupmod -g 1020 developers; \ # usermod -s /bin/sh tester; \ # " FEATURE_PACKAGES FEATURE_PACKAGES[doc] = "Defines one or more packages to include in an image when a specific item is included in IMAGE_FEATURES. When setting the value, FEATURE_PACKAGES should have the name of the feature item as an override." Defines one or more packages to include in an image when a specific item is included in IMAGE_FEATURES. When setting the value, FEATURE_PACKAGES should have the name of the feature item as an override. Here is an example: FEATURE_PACKAGES_widget = "package1 package2" In this example, if "widget" were added to IMAGE_FEATURES, package1 and package2 would be included in the image. Packages installed by features defined through FEATURE_PACKAGES are often package groups. While similarly named, you should not confuse the FEATURE_PACKAGES variable with package groups, which are discussed elsewhere in the documentation. FEED_DEPLOYDIR_BASE_URI FEED_DEPLOYDIR_BASE_URI[doc] = "Allow to serve ipk deploy directory as an ad hoc feed (bogofeed). Set to base URL of the directory as exported by HTTP. Set of ad hoc feed configs will be generated in the image." Points to the base URL of the server and location within the document-root that provides the metadata and packages required by OPKG to support runtime package management of IPK packages. You set this variable in your local.conf file. Consider the following example: FEED_DEPLOYDIR_BASE_URI = "http://192.168.7.1/BOARD-dir" This example assumes you are serving your packages over HTTP and your databases are located in a directory named BOARD-dir, which is underneath your HTTP server's document-root. In this case, the OpenEmbedded build system generates a set of configuration files for you in your target that work with the feed. FILES FILES[doc] = "The list of directories or files that are placed in a package." The list of files and directories that are placed in a package. The PACKAGES variable lists the packages generated by a recipe. To use the FILES variable, provide a package name override that identifies the resulting package. Then, provide a space-separated list of files or paths that identify the files you want included as part of the resulting package. Here is an example: FILES_${PN} += "${bindir}/mydir1 ${bindir}/mydir2/myfile" When specifying paths as part of the FILES variable, it is good practice to use appropriate path variables. For example, use ${sysconfdir} rather than /etc, or ${bindir} rather than /usr/bin. You can find a list of these variables at the top of the meta/conf/bitbake.conf file in the Source Directory. You will also find the default values of the various FILES_* variables in this file. If some of the files you provide with the FILES variable are editable and you know they should not be overwritten during the package update process by the Package Management System (PMS), you can identify these files so that the PMS will not overwrite them. See the CONFFILES variable for information on how to identify these files to the PMS. FILES_SOLIBSDEV FILES_SOLIBSDEV[doc] = "Defines the full path name of the development symbolic link (symlink) for shared libraries on the target platform." Defines the file specification to match SOLIBSDEV. In other words, FILES_SOLIBSDEV defines the full path name of the development symbolic link (symlink) for shared libraries on the target platform. The following statement from the bitbake.conf shows how it is set: FILES_SOLIBSDEV ?= "${base_libdir}/lib*${SOLIBSDEV} ${libdir}/lib*${SOLIBSDEV}" FILESEXTRAPATHS FILESEXTRAPATHS[doc] = "Extends the search path the OpenEmbedded build system uses when looking for files and patches as it processes recipes and append files." Extends the search path the OpenEmbedded build system uses when looking for files and patches as it processes recipes and append files. The default directories BitBake uses when it processes recipes are initially defined by the FILESPATH variable. You can extend FILESPATH variable by using FILESEXTRAPATHS. Best practices dictate that you accomplish this by using FILESEXTRAPATHS from within a .bbappend file and that you prepend paths as follows: FILESEXTRAPATHS_prepend := "${THISDIR}/${PN}:" In the above example, the build system first looks for files in a directory that has the same name as the corresponding append file. When extending FILESEXTRAPATHS, be sure to use the immediate expansion (:=) operator. Immediate expansion makes sure that BitBake evaluates THISDIR at the time the directive is encountered rather than at some later time when expansion might result in a directory that does not contain the files you need. Also, include the trailing separating colon character if you are prepending. The trailing colon character is necessary because you are directing BitBake to extend the path by prepending directories to the search path. Here is another common use: FILESEXTRAPATHS_prepend := "${THISDIR}/files:" In this example, the build system extends the FILESPATH variable to include a directory named files that is in the same directory as the corresponding append file. Here is a final example that specifically adds three paths: FILESEXTRAPATHS_prepend := "path_1:path_2:path_3:" By prepending paths in .bbappend files, you allow multiple append files that reside in different layers but are used for the same recipe to correctly extend the path. FILESOVERRIDES FILESOVERRIDES[doc] = "A subset of OVERRIDES used by the OpenEmbedded build system for creating FILESPATH." A subset of OVERRIDES used by the OpenEmbedded build system for creating FILESPATH. You can find more information on how overrides are handled in the BitBake Manual. By default, the FILESOVERRIDES variable is defined as: FILESOVERRIDES = "${TRANSLATED_TARGET_ARCH}:${MACHINEOVERRIDES}:${DISTROOVERRIDES}" Do not hand-edit the FILESOVERRIDES variable. The values match up with expected overrides and are used in an expected manner by the build system. FILESPATH FILESPATH[doc] = "The default set of directories the OpenEmbedded build system uses when searching for patches and files. It is defined in the base.bbclass class found in meta/classes in the Source Directory. Do not hand-edit the FILESPATH variable." The default set of directories the OpenEmbedded build system uses when searching for patches and files. During the build process, BitBake searches each directory in FILESPATH in the specified order when looking for files and patches specified by each file:// URI in a recipe. The default value for the FILESPATH variable is defined in the base.bbclass class found in meta/classes in the Source Directory: FILESPATH = "${@base_set_filespath(["${FILE_DIRNAME}/${BP}", \ "${FILE_DIRNAME}/${BPN}", "${FILE_DIRNAME}/files"], d)}" Do not hand-edit the FILESPATH variable. If you want the build system to look in directories other than the defaults, extend the FILESPATH variable by using the FILESEXTRAPATHS variable. Be aware that the default FILESPATH directories do not map to directories in custom layers where append files (.bbappend) are used. If you want the build system to find patches or files that reside with your append files, you need to extend the FILESPATH variable by using the FILESEXTRAPATHS variable. FILESYSTEM_PERMS_TABLES FILESYSTEM_PERMS_TABLES[doc] = "Allows you to define your own file permissions settings table as part of your configuration for the packaging process." Allows you to define your own file permissions settings table as part of your configuration for the packaging process. For example, suppose you need a consistent set of custom permissions for a set of groups and users across an entire work project. It is best to do this in the packages themselves but this is not always possible. By default, the OpenEmbedded build system uses the fs-perms.txt, which is located in the meta/files folder in the Source Directory. If you create your own file permissions setting table, you should place it in your layer or the distro's layer. You define the FILESYSTEM_PERMS_TABLES variable in the conf/local.conf file, which is found in the Build Directory, to point to your custom fs-perms.txt. You can specify more than a single file permissions setting table. The paths you specify to these files must be defined within the BBPATH variable. For guidance on how to create your own file permissions settings table file, examine the existing fs-perms.txt. FONT_EXTRA_RDEPENDS FONT_EXTRA_RDEPENDS[doc] = "When a recipe inherits the fontcache class, this variable specifies runtime dependencies for font packages. This variable defaults to 'fontconfig-utils'." When inheriting the fontcache class, this variable specifies the runtime dependencies for font packages. By default, the FONT_EXTRA_RDEPENDS is set to "fontconfig-utils". FONT_PACKAGES FONT_PACKAGES[doc] = "When a recipe inherits the fontcache class, this variable identifies packages containing font files that need to be cached by Fontconfig." When inheriting the fontcache class, this variable identifies packages containing font files that need to be cached by Fontconfig. By default, the fontcache class assumes that fonts are in the recipe's main package (i.e. ${PN}). Use this variable if fonts you need are in a package other than that main package. FORCE_RO_REMOVE FORCE_RO_REMOVE[doc] = "Forces the removal of the packages listed in ROOTFS_RO_UNNEEDED during the generation of the root filesystem." Forces the removal of the packages listed in ROOTFS_RO_UNNEEDED during the generation of the root filesystem. Set the variable to "1" to force the removal of these packages. FULL_OPTIMIZATION FULL_OPTIMIZATION[doc]= "The options to pass in TARGET_CFLAGS and CFLAGS when compiling an optimized system. This variable defaults to '-fexpensive-optimizations -fomit-frame-pointer -frename-registers -O2'." The options to pass in TARGET_CFLAGS and CFLAGS when compiling an optimized system. This variable defaults to "-O2 -pipe ${DEBUG_FLAGS}". GDB GDB[doc] = "The minimal command and arguments to run the GNU Debugger." The minimal command and arguments to run the GNU Debugger. GITDIR GITDIR[doc] = "The directory where Git clones will be stored." The directory in which a local copy of a Git repository is stored when it is cloned. GLIBC_GENERATE_LOCALES GLIBC_GENERATE_LOCALES[doc]= "Specifies the list of GLIBC locales to generate should you not wish generate all LIBC locals, which can be time consuming." Specifies the list of GLIBC locales to generate should you not wish generate all LIBC locals, which can be time consuming. If you specifically remove the locale en_US.UTF-8, you must set IMAGE_LINGUAS appropriately. You can set GLIBC_GENERATE_LOCALES in your local.conf file. By default, all locales are generated. GLIBC_GENERATE_LOCALES = "en_GB.UTF-8 en_US.UTF-8" GROUPADD_PARAM GROUPADD_PARAM[doc] = "When a recipe inherits the useradd class, this variable specifies for a package what parameters should be passed to the groupadd command if you wish to add a group to the system when the package is installed." When inheriting the useradd class, this variable specifies for a package what parameters should be passed to the groupadd command if you wish to add a group to the system when the package is installed. Here is an example from the dbus recipe: GROUPADD_PARAM_${PN} = "-r netdev" For information on the standard Linux shell command groupadd, see . GROUPMEMS_PARAM GROUPMEMS_PARAM[doc] = "When a recipe inherits the useradd class, this variable specifies for a package what parameters should be passed to the groupmems command if you wish to modify the members of a group when the package is installed." When inheriting the useradd class, this variable specifies for a package what parameters should be passed to the groupmems command if you wish to modify the members of a group when the package is installed. For information on the standard Linux shell command groupmems, see . GRUB_GFXSERIAL GRUB_GFXSERIAL[doc] = "Configures the GNU GRand Unified Bootloader (GRUB) to have graphics and serial in the boot menu." Configures the GNU GRand Unified Bootloader (GRUB) to have graphics and serial in the boot menu. Set this variable to "1" in your local.conf or distribution configuration file to enable graphics and serial in the menu. See the grub-efi class for more information on how this variable is used. GRUB_OPTS GRUB_OPTS[doc] = "Additional options to add to the GNU GRand Unified Bootloader (GRUB) configuration." Additional options to add to the GNU GRand Unified Bootloader (GRUB) configuration. Use a semi-colon character (;) to separate multiple options. The GRUB_OPTS variable is optional. See the grub-efi class for more information on how this variable is used. GRUB_TIMEOUT GRUB_TIMEOUT[doc] = "Specifies the timeout before executing the default LABEL in the GNU GRand Unified Bootloader (GRUB)." Specifies the timeout before executing the default LABEL in the GNU GRand Unified Bootloader (GRUB). The GRUB_TIMEOUT variable is optional. See the grub-efi class for more information on how this variable is used. GTKIMMODULES_PACKAGES GTKIMMODULES_PACKAGES[doc] = "For recipes that inherit the gtk-immodules-cache class, this variable specifies the packages that contain the GTK+ input method modules being installed when the modules are in packages other than the main package." When inheriting the gtk-immodules-cache class, this variable specifies the packages that contain the GTK+ input method modules being installed when the modules are in packages other than the main package. HOMEPAGE HOMEPAGE[doc] = "Website where more information about the software the recipe is building can be found." Website where more information about the software the recipe is building can be found. HOST_ARCH HOST_ARCH[doc] = "The name of the target architecture. Normally same as the TARGET_ARCH." The name of the target architecture, which is normally the same as TARGET_ARCH. The OpenEmbedded build system supports many architectures. Here is an example list of architectures supported. This list is by no means complete as the architecture is configurable: arm i586 x86_64 powerpc powerpc64 mips mipsel HOST_CC_ARCH HOST_CC_ARCH[doc] = "The name of the host architecture. Normally same as the TARGET_CC_ARCH." Specifies architecture-specific compiler flags that are passed to the C compiler. Default initialization for HOST_CC_ARCH varies depending on what is being built: TARGET_CC_ARCH when building for the target BUILD_CC_ARCH when building for the build host (i.e. -native) BUILDSDK_CC_ARCH when building for an SDK (i.e. nativesdk-) HOST_OS HOST_OS[doc] = "The name of the target operating system. Normally the same as the TARGET_OS." Specifies the name of the target operating system, which is normally the same as the TARGET_OS. The variable can be set to "linux" for glibc-based systems and to "linux-uclibc" for uclibc. For ARM/EABI targets, there are also "linux-gnueabi" and "linux-uclibc-gnueabi" values possible. HOST_PREFIX HOST_PREFIX[doc] = "The prefix for the cross compile toolchain. Normally same as the TARGET_PREFIX." Specifies the prefix for the cross-compile toolchain. HOST_PREFIX is normally the same as TARGET_PREFIX. HOST_SYS HOST_SYS[doc] = "Specifies the system, including the architecture and the operating system, for with the build is occurring in the context of the current recipe." Specifies the system, including the architecture and the operating system, for which the build is occurring in the context of the current recipe. The OpenEmbedded build system automatically sets this variable based on HOST_ARCH, HOST_VENDOR, and HOST_OS variables. You do not need to set the variable yourself. Consider these two examples: Given a native recipe on a 32-bit x86 machine running Linux, the value is "i686-linux". Given a recipe being built for a little-endian MIPS target running Linux, the value might be "mipsel-linux". HOSTTOOLS HOSTTOOLS[doc] = "A space-separated list (filter) of tools on the build host that should be allowed to be called from within build tasks." A space-separated list (filter) of tools on the build host that should be allowed to be called from within build tasks. Using this filter helps reduce the possibility of host contamination. If a tool specified in the value of HOSTTOOLS is not found on the build host, the OpenEmbedded build system produces an error and the build is not started. For additional information, see HOSTTOOLS_NONFATAL. HOSTTOOLS_NONFATAL HOSTTOOLS_NONFATAL[doc] = "A space-separated list (filter) of tools on the build host that should be allowed to be called from within build tasks." A space-separated list (filter) of tools on the build host that should be allowed to be called from within build tasks. Using this filter helps reduce the possibility of host contamination. Unlike HOSTTOOLS, the OpenEmbedded build system does not produce and error if a tool specified in the value of HOSTTOOLS_NONFATAL is not found on the build host. Thus, you can use HOSTTOOLS_NONFATAL to filter optional host tools. HOST_VENDOR HOST_VENDOR[doc] = "The name of the vendor. Normally same as the TARGET_VENDOR." Specifies the name of the vendor. HOST_VENDOR is normally the same as TARGET_VENDOR. ICECC_DISABLED ICECC_DISABLED[doc] = "Disables or enables the icecc (Icecream) function." Disables or enables the icecc (Icecream) function. For more information on this function and best practices for using this variable, see the "icecc.bbclass" section. Setting this variable to "1" in your local.conf disables the function: ICECC_DISABLED ??= "1" To enable the function, set the variable as follows: ICECC_DISABLED = "" ICECC_ENV_EXEC ICECC_ENV_EXEC[doc] = "Points to the icecc-create-env script that you provide." Points to the icecc-create-env script that you provide. This variable is used by the icecc class. You set this variable in your local.conf file. If you do not point to a script that you provide, the OpenEmbedded build system uses the default script provided by the icecc-create-env.bb recipe, which is a modified version and not the one that comes with icecc. ICECC_PARALLEL_MAKE ICECC_PARALLEL_MAKE[doc] = "Extra options passed to the make command during the do_compile task that specify parallel compilation." Extra options passed to the make command during the do_compile task that specify parallel compilation. This variable usually takes the form of "-j x", where x represents the maximum number of parallel threads make can run. The options passed affect builds on all enabled machines on the network, which are machines running the iceccd daemon. If your enabled machines support multiple cores, coming up with the maximum number of parallel threads that gives you the best performance could take some experimentation since machine speed, network lag, available memory, and existing machine loads can all affect build time. Consequently, unlike the PARALLEL_MAKE variable, there is no rule-of-thumb for setting ICECC_PARALLEL_MAKE to achieve optimal performance. If you do not set ICECC_PARALLEL_MAKE, the build system does not use it (i.e. the system does not detect and assign the number of cores as is done with PARALLEL_MAKE). ICECC_PATH ICECC_PATH[doc] = "The location of the icecc binary." The location of the icecc binary. You can set this variable in your local.conf file. If your local.conf file does not define this variable, the icecc class attempts to define it by locating icecc using which. ICECC_USER_CLASS_BL ICECC_USER_CLASS_BL[doc] = "Identifies user classes that you do not want the Icecream distributed compile support to consider." Identifies user classes that you do not want the Icecream distributed compile support to consider. This variable is used by the icecc class. You set this variable in your local.conf file. When you list classes using this variable, you are "blacklisting" them from distributed compilation across remote hosts. Any classes you list will be distributed and compiled locally. ICECC_USER_PACKAGE_BL ICECC_USER_PACKAGE_BL[doc] = "Identifies user recipes that you do not want the Icecream distributed compile support to consider." Identifies user recipes that you do not want the Icecream distributed compile support to consider. This variable is used by the icecc class. You set this variable in your local.conf file. When you list packages using this variable, you are "blacklisting" them from distributed compilation across remote hosts. Any packages you list will be distributed and compiled locally. ICECC_USER_PACKAGE_WL ICECC_USER_PACKAGE_WL[doc] = "Identifies user recipes that use an empty PARALLEL_MAKE variable that you want to force remote distributed compilation on using the Icecream distributed compile support." Identifies user recipes that use an empty PARALLEL_MAKE variable that you want to force remote distributed compilation on using the Icecream distributed compile support. This variable is used by the icecc class. You set this variable in your local.conf file. IMAGE_BASENAME IMAGE_BASENAME[doc] = "The base name of image output files." The base name of image output files. This variable defaults to the recipe name (${PN}). IMAGE_BOOT_FILES IMAGE_BOOT_FILES[doc] = "Whitespace separated list of files from ${DEPLOY_DIR_IMAGE} to place in boot partition. Entries will be installed under a same name as the source file. To change the destination file name, pass a desired name after a semicolon (eg. u-boot.img;uboot)." A space-separated list of files installed into the boot partition when preparing an image using the wic tool with the bootimg-partition source plugin. By default, the files are installed under the same name as the source files. To change the installed name, separate it from the original name with a semi-colon (;). Source files need to be located in DEPLOY_DIR_IMAGE. Here are two examples: IMAGE_BOOT_FILES = "u-boot.img uImage;kernel" IMAGE_BOOT_FILES = "u-boot.${UBOOT_SUFFIX} ${KERNEL_IMAGETYPE}" Alternatively, source files can be picked up using a glob pattern. In this case, the destination file will have the same name as the base name of the source file path. To install files into a directory within the target location, pass its name after a semi-colon (;). Here are two examples: IMAGE_BOOT_FILES = "bcm2835-bootfiles/*" IMAGE_BOOT_FILES = "bcm2835-bootfiles/*;boot/" The first example installs all files from ${DEPLOY_DIR_IMAGE}/bcm2835-bootfiles into the root of the target partition. The second example installs the same files into a boot directory within the target partition. IMAGE_CLASSES IMAGE_CLASSES[doc] = "A list of classes that all images should inherit." A list of classes that all images should inherit. You typically use this variable to specify the list of classes that register the different types of images the OpenEmbedded build system creates. The default value for IMAGE_CLASSES is image_types. You can set this variable in your local.conf or in a distribution configuration file. For more information, see meta/classes/image_types.bbclass in the Source Directory. IMAGE_CMD IMAGE_CMD[doc] = "Specifies the command to create the image file for a specific image type, which corresponds to the value set set in IMAGE_FSTYPES, (e.g. ext3, btrfs, and so forth)." Specifies the command to create the image file for a specific image type, which corresponds to the value set set in IMAGE_FSTYPES, (e.g. ext3, btrfs, and so forth). When setting this variable, you should use an override for the associated type. Here is an example: IMAGE_CMD_jffs2 = "mkfs.jffs2 --root=${IMAGE_ROOTFS} \ --faketime --output=${DEPLOY_DIR_IMAGE}/${IMAGE_NAME}.rootfs.jffs2 \ ${EXTRA_IMAGECMD}" You typically do not need to set this variable unless you are adding support for a new image type. For more examples on how to set this variable, see the image_types class file, which is meta/classes/image_types.bbclass. IMAGE_DEVICE_TABLES IMAGE_DEVICE_TABLES[doc] = "Specifies one or more files that contain custom device tables that are passed to the makedevs command as part of creating an image." Specifies one or more files that contain custom device tables that are passed to the makedevs command as part of creating an image. These files list basic device nodes that should be created under /dev within the image. If IMAGE_DEVICE_TABLES is not set, files/device_table-minimal.txt is used, which is located by BBPATH. For details on how you should write device table files, see meta/files/device_table-minimal.txt as an example. IMAGE_FEATURES IMAGE_FEATURES[doc] = "The primary list of features to include in an image. Configure this variable in an image recipe." The primary list of features to include in an image. Typically, you configure this variable in an image recipe. Although you can use this variable from your local.conf file, which is found in the Build Directory, best practices dictate that you do not. To enable extra features from outside the image recipe, use the EXTRA_IMAGE_FEATURES variable. For a list of image features that ships with the Yocto Project, see the "Image Features" section. For an example that shows how to customize your image by using this variable, see the "Customizing Images Using Custom IMAGE_FEATURES and EXTRA_IMAGE_FEATURES" section in the Yocto Project Development Manual. IMAGE_FSTYPES IMAGE_FSTYPES[doc] = "Formats of root filesystem images that you want to have created." Specifies the formats the OpenEmbedded build system uses during the build when creating the root filesystem. For example, setting IMAGE_FSTYPES as follows causes the build system to create root filesystems using two formats: .ext3 and .tar.bz2: IMAGE_FSTYPES = "ext3 tar.bz2" For the complete list of supported image formats from which you can choose, see IMAGE_TYPES. If you add "live" to IMAGE_FSTYPES inside an image recipe, be sure that you do so prior to the "inherit image" line of the recipe or the live image will not build. Due to the way this variable is processed, it is not possible to update its contents using _append or _prepend. To add one or more additional options to this variable the += operator must be used. IMAGE_INSTALL IMAGE_INSTALL[doc] = "Specifies the packages to install into an image. Image recipes set IMAGE_INSTALL to specify the packages to install into an image through image.bbclass." Specifies the packages to install into an image. The IMAGE_INSTALL variable is a mechanism for an image recipe and you should use it with care to avoid ordering issues. When working with an core-image-minimal-initramfs image, do not use the IMAGE_INSTALL variable to specify packages for installation. Instead, use the PACKAGE_INSTALL variable, which allows the initial RAM filesystem (initramfs) recipe to use a fixed set of packages and not be affected by IMAGE_INSTALL. For information on creating an initramfs, see the "Building an Initial RAM Filesystem (initramfs) Image" section in the Yocto Project Development Manual. Image recipes set IMAGE_INSTALL to specify the packages to install into an image through image.bbclass. Additionally, "helper" classes exist, such as core-image.bbclass, that can take IMAGE_FEATURES lists and turn these into auto-generated entries in IMAGE_INSTALL in addition to its default contents. Using IMAGE_INSTALL with the += operator from the /conf/local.conf file or from within an image recipe is not recommended as it can cause ordering issues. Since core-image.bbclass sets IMAGE_INSTALL to a default value using the ?= operator, using a += operation against IMAGE_INSTALL will result in unexpected behavior when used in conf/local.conf. Furthermore, the same operation from within an image recipe may or may not succeed depending on the specific situation. In both these cases, the behavior is contrary to how most users expect the += operator to work. When you use this variable, it is best to use it as follows: IMAGE_INSTALL_append = " package-name" Be sure to include the space between the quotation character and the start of the package name or names. IMAGE_LINGUAS IMAGE_LINGUAS[doc] = "Specifies the list of locales to install into the image during the root filesystem construction process." Specifies the list of locales to install into the image during the root filesystem construction process. The OpenEmbedded build system automatically splits locale files, which are used for localization, into separate packages. Setting the IMAGE_LINGUAS variable ensures that any locale packages that correspond to packages already selected for installation into the image are also installed. Here is an example: IMAGE_LINGUAS = "pt-br de-de" In this example, the build system ensures any Brazilian Portuguese and German locale files that correspond to packages in the image are installed (i.e. *-locale-pt-br and *-locale-de-de as well as *-locale-pt and *-locale-de, since some software packages only provide locale files by language and not by country-specific language). See the GLIBC_GENERATE_LOCALES variable for information on generating GLIBC locales. IMAGE_MANIFEST IMAGE_MANIFEST[doc] = "The manifest file for the image. This file lists all the installed packages that make up the image." The manifest file for the image. This file lists all the installed packages that make up the image. The file contains package information on a line-per-package basis as follows: packagename packagearch version The image class defines the manifest file as follows: IMAGE_MANIFEST = "${DEPLOY_DIR_IMAGE}/${IMAGE_NAME}.rootfs.manifest" The location is derived using the DEPLOY_DIR_IMAGE and IMAGE_NAME variables. You can find information on how the image is created in the "Image Generation" section. IMAGE_NAME IMAGE_NAME[doc] = "The name of the output image files minus the extension." The name of the output image files minus the extension. This variable is derived using the IMAGE_BASENAME, MACHINE, and DATETIME variables: IMAGE_NAME = "${IMAGE_BASENAME}-${MACHINE}-${DATETIME}" IMAGE_OVERHEAD_FACTOR IMAGE_OVERHEAD_FACTOR[doc] = "Defines a multiplier that the build system applies to the initial image size for cases when the multiplier times the returned disk usage value for the image is greater than the sum of IMAGE_ROOTFS_SIZE and IMAGE_ROOTFS_EXTRA_SPACE." Defines a multiplier that the build system applies to the initial image size for cases when the multiplier times the returned disk usage value for the image is greater than the sum of IMAGE_ROOTFS_SIZE and IMAGE_ROOTFS_EXTRA_SPACE. The result of the multiplier applied to the initial image size creates free disk space in the image as overhead. By default, the build process uses a multiplier of 1.3 for this variable. This default value results in 30% free disk space added to the image when this method is used to determine the final generated image size. You should be aware that post install scripts and the package management system uses disk space inside this overhead area. Consequently, the multiplier does not produce an image with all the theoretical free disk space. See IMAGE_ROOTFS_SIZE for information on how the build system determines the overall image size. The default 30% free disk space typically gives the image enough room to boot and allows for basic post installs while still leaving a small amount of free disk space. If 30% free space is inadequate, you can increase the default value. For example, the following setting gives you 50% free space added to the image: IMAGE_OVERHEAD_FACTOR = "1.5" Alternatively, you can ensure a specific amount of free disk space is added to the image by using the IMAGE_ROOTFS_EXTRA_SPACE variable. IMAGE_PKGTYPE IMAGE_PKGTYPE[doc] = "Defines the package type (DEB, RPM, IPK, or TAR) used by the OpenEmbedded build system." Defines the package type (DEB, RPM, IPK, or TAR) used by the OpenEmbedded build system. The variable is defined appropriately by the package_deb, package_rpm, package_ipk, or package_tar class. The package_tar class is broken and is not supported. It is recommended that you do not use it. The populate_sdk_* and image classes use the IMAGE_PKGTYPE for packaging up images and SDKs. You should not set the IMAGE_PKGTYPE manually. Rather, the variable is set indirectly through the appropriate package_* class using the PACKAGE_CLASSES variable. The OpenEmbedded build system uses the first package type (e.g. DEB, RPM, or IPK) that appears with the variable Files using the .tar format are never used as a substitute packaging format for DEB, RPM, and IPK formatted files for your image or SDK. IMAGE_POSTPROCESS_COMMAND IMAGE_POSTPROCESS_COMMAND[doc] = "Specifies a list of functions to call once the OpenEmbedded build system has created the final image output files." Specifies a list of functions to call once the OpenEmbedded build system has created the final image output files. You can specify functions separated by semicolons: IMAGE_POSTPROCESS_COMMAND += "function; ... " If you need to pass the root filesystem path to a command within the function, you can use ${IMAGE_ROOTFS}, which points to the directory that becomes the root filesystem image. See the IMAGE_ROOTFS variable for more information. IMAGE_PREPROCESS_COMMAND IMAGE_PREPROCESS_COMMAND[doc] = "Specifies a list of functions to call before the OpenEmbedded build system has created the final image output files." Specifies a list of functions to call before the OpenEmbedded build system has created the final image output files. You can specify functions separated by semicolons: IMAGE_PREPROCESS_COMMAND += "function; ... " If you need to pass the root filesystem path to a command within the function, you can use ${IMAGE_ROOTFS}, which points to the directory that becomes the root filesystem image. See the IMAGE_ROOTFS variable for more information. IMAGE_ROOTFS IMAGE_ROOTFS[doc] = "The location of the root filesystem while it is under construction (i.e. during do_rootfs)." The location of the root filesystem while it is under construction (i.e. during the do_rootfs task). This variable is not configurable. Do not change it. IMAGE_ROOTFS_ALIGNMENT IMAGE_ROOTFS_ALIGNMENT[doc] = "Specifies the alignment for the output image file in Kbytes." Specifies the alignment for the output image file in Kbytes. If the size of the image is not a multiple of this value, then the size is rounded up to the nearest multiple of the value. The default value is "1". See IMAGE_ROOTFS_SIZE for additional information. IMAGE_ROOTFS_EXTRA_SPACE IMAGE_ROOTFS_EXTRA_SPACE[doc] = "Defines additional free disk space created in the image in Kbytes. By default, this variable is set to '0'." Defines additional free disk space created in the image in Kbytes. By default, this variable is set to "0". This free disk space is added to the image after the build system determines the image size as described in IMAGE_ROOTFS_SIZE. This variable is particularly useful when you want to ensure that a specific amount of free disk space is available on a device after an image is installed and running. For example, to be sure 5 Gbytes of free disk space is available, set the variable as follows: IMAGE_ROOTFS_EXTRA_SPACE = "5242880" For example, the Yocto Project Build Appliance specifically requests 40 Gbytes of extra space with the line: IMAGE_ROOTFS_EXTRA_SPACE = "41943040" IMAGE_ROOTFS_SIZE IMAGE_ROOTFS_SIZE[doc] = "Defines the size in Kbytes for the generated image." Defines the size in Kbytes for the generated image. The OpenEmbedded build system determines the final size for the generated image using an algorithm that takes into account the initial disk space used for the generated image, a requested size for the image, and requested additional free disk space to be added to the image. Programatically, the build system determines the final size of the generated image as follows: if (image-du * overhead) < rootfs-size: internal-rootfs-size = rootfs-size + xspace else: internal-rootfs-size = (image-du * overhead) + xspace where: image-du = Returned value of the du command on the image. overhead = IMAGE_OVERHEAD_FACTOR rootfs-size = IMAGE_ROOTFS_SIZE internal-rootfs-size = Initial root filesystem size before any modifications. xspace = IMAGE_ROOTFS_EXTRA_SPACE See the IMAGE_OVERHEAD_FACTOR and IMAGE_ROOTFS_EXTRA_SPACE variables for related information. IMAGE_TYPEDEP IMAGE_TYPEDEP[doc] = "Specifies a dependency from one image type on another." Specifies a dependency from one image type on another. Here is an example from the image-live class: IMAGE_TYPEDEP_live = "ext3" In the previous example, the variable ensures that when "live" is listed with the IMAGE_FSTYPES variable, the OpenEmbedded build system produces an ext3 image first since one of the components of the live image is an ext3 formatted partition containing the root filesystem. IMAGE_TYPES IMAGE_TYPES[doc] = "Specifies the complete list of supported image types by default." Specifies the complete list of supported image types by default: btrfs cpio cpio.gz cpio.lz4 cpio.lzma cpio.xz cramfs elf ext2 ext2.bz2 ext2.gz ext2.lzma ext3 ext3.gz ext4 ext4.gz hdddirect hddimg iso jffs2 jffs2.sum multiubi qcow2 squashfs squashfs-lzo squashfs-xz tar tar.bz2 tar.gz tar.lz4 tar.xz ubi ubifs vdi vmdk wic wic.bz2 wic.gz wic.lzma For more information about these types of images, see meta/classes/image_types*.bbclass in the Source Directory. INC_PR INC_PR[doc] = "Helps define the recipe revision for recipes that share a common include file." Helps define the recipe revision for recipes that share a common include file. You can think of this variable as part of the recipe revision as set from within an include file. Suppose, for example, you have a set of recipes that are used across several projects. And, within each of those recipes the revision (its PR value) is set accordingly. In this case, when the revision of those recipes changes, the burden is on you to find all those recipes and be sure that they get changed to reflect the updated version of the recipe. In this scenario, it can get complicated when recipes that are used in many places and provide common functionality are upgraded to a new revision. A more efficient way of dealing with this situation is to set the INC_PR variable inside the include files that the recipes share and then expand the INC_PR variable within the recipes to help define the recipe revision. The following provides an example that shows how to use the INC_PR variable given a common include file that defines the variable. Once the variable is defined in the include file, you can use the variable to set the PR values in each recipe. You will notice that when you set a recipe's PR you can provide more granular revisioning by appending values to the INC_PR variable: recipes-graphics/xorg-font/xorg-font-common.inc:INC_PR = "r2" recipes-graphics/xorg-font/encodings_1.0.4.bb:PR = "${INC_PR}.1" recipes-graphics/xorg-font/font-util_1.3.0.bb:PR = "${INC_PR}.0" recipes-graphics/xorg-font/font-alias_1.0.3.bb:PR = "${INC_PR}.3" The first line of the example establishes the baseline revision to be used for all recipes that use the include file. The remaining lines in the example are from individual recipes and show how the PR value is set. INCOMPATIBLE_LICENSE INCOMPATIBLE_LICENSE[doc] = "Specifies a space-separated list of license names (as they would appear in LICENSE) that should be excluded from the build." Specifies a space-separated list of license names (as they would appear in LICENSE) that should be excluded from the build. Recipes that provide no alternatives to listed incompatible licenses are not built. Packages that are individually licensed with the specified incompatible licenses will be deleted. This functionality is only regularly tested using the following setting: INCOMPATIBLE_LICENSE = "GPL-3.0 LGPL-3.0 AGPL-3.0" Although you can use other settings, you might be required to remove dependencies on or provide alternatives to components that are required to produce a functional system image. INHERIT INHERIT[doc] = "Causes the named class or classes to be inherited globally." Causes the named class or classes to be inherited globally. Anonymous functions in the class or classes are not executed for the base configuration and in each individual recipe. The OpenEmbedded build system ignores changes to INHERIT in individual recipes. For more information on INHERIT, see the "INHERIT Configuration Directive" section in the Yocto Project Bitbake User Manual. INHERIT_DISTRO INHERIT_DISTRO[doc] = "Lists classes that will be inherited at the distribution level. It is unlikely that you want to edit this variable." Lists classes that will be inherited at the distribution level. It is unlikely that you want to edit this variable. The default value of the variable is set as follows in the meta/conf/distro/defaultsetup.conf file: INHERIT_DISTRO ?= "debian devshell sstate license" INHIBIT_DEFAULT_DEPS INHIBIT_DEFAULT_DEPS[doc] = "Prevents the default dependencies, namely the C compiler and standard C library (libc), from being added to DEPENDS." Prevents the default dependencies, namely the C compiler and standard C library (libc), from being added to DEPENDS. This variable is usually used within recipes that do not require any compilation using the C compiler. Set the variable to "1" to prevent the default dependencies from being added. INHIBIT_PACKAGE_DEBUG_SPLIT INHIBIT_PACKAGE_DEBUG_SPLIT[doc] = "If set to "1", prevents the OpenEmbedded build system from splitting out debug information during packaging" Prevents the OpenEmbedded build system from splitting out debug information during packaging. By default, the build system splits out debugging information during the do_package task. For more information on how debug information is split out, see the PACKAGE_DEBUG_SPLIT_STYLE variable. To prevent the build system from splitting out debug information during packaging, set the INHIBIT_PACKAGE_DEBUG_SPLIT variable as follows: INHIBIT_PACKAGE_DEBUG_SPLIT = "1" INHIBIT_PACKAGE_STRIP INHIBIT_PACKAGE_STRIP[doc] = "If set to "1", causes the build to not strip binaries in resulting packages." If set to "1", causes the build to not strip binaries in resulting packages and prevents the -dbg package from containing the source files. By default, the OpenEmbedded build system strips binaries and puts the debugging symbols into ${PN}-dbg. Consequently, you should not set INHIBIT_PACKAGE_STRIP when you plan to debug in general. INITRAMFS_FSTYPES INITRAMFS_FSTYPES[doc] = "Defines the format for the output image of an initial RAM filesystem (initramfs), which is used during boot." Defines the format for the output image of an initial RAM filesystem (initramfs), which is used during boot. Supported formats are the same as those supported by the IMAGE_FSTYPES variable. The default value of this variable, which is set in the meta/conf/bitbake.conf configuration file in the Source Directory, is "cpio.gz". The Linux kernel's initramfs mechanism, as opposed to the initial RAM filesystem initrd mechanism, expects an optionally compressed cpio archive. INITRAMFS_IMAGE INITRAMFS_IMAGE[doc] = "Specifies the PROVIDES name of an image recipe that is used to build an initial RAM filesystem (initramfs) image." Specifies the PROVIDES name of an image recipe that is used to build an initial RAM filesystem (initramfs) image. An initramfs provides a temporary root filesystem used for early system initialization (e.g. loading of modules needed to locate and mount the "real" root filesystem). The specified recipe is added as a dependency of the root filesystem recipe (e.g. core-image-sato). See the meta/recipes-core/images/core-image-minimal-initramfs.bb recipe in the Source Directory for an example initramfs recipe. To select this recipe to provide the initramfs, set INITRAMFS_IMAGE to "core-image-minimal-initramfs". The initramfs image recipe should set IMAGE_FSTYPES to INITRAMFS_FSTYPES. You can also find more information by referencing the meta/poky/conf/local.conf.sample.extended configuration file in the Source Directory, the image class, and the kernel class to see how to use the INITRAMFS_IMAGE variable. If INITRAMFS_IMAGE is empty, which is the default, then no initramfs is built. For more information, you can also see the INITRAMFS_IMAGE_BUNDLE variable, which allows the generated image to be bundled inside the kernel image. Additionally, for information on creating an initramfs, see the "Building an Initial RAM Filesystem (initramfs) Image" section in the Yocto Project Development Manual. INITRAMFS_IMAGE_BUNDLE INITRAMFS_IMAGE_BUNDLE[doc] = "Controls whether or not the image recipe specified by INITRAMFS_IMAGE is run through an extra pass (do_bundle_initramfs) during kernel compilation in order to build a single binary that contains both the kernel image and the initial RAM filesystem (initramfs)." Controls whether or not the image recipe specified by INITRAMFS_IMAGE is run through an extra pass (do_bundle_initramfs) during kernel compilation in order to build a single binary that contains both the kernel image and the initial RAM filesystem (initramfs) image. This makes use of the CONFIG_INITRAMFS_SOURCE kernel feature. Using an extra compilation pass to bundle the initramfs avoids a circular dependency between the kernel recipe and the initramfs recipe should the initramfs include kernel modules. Should that be the case, the initramfs recipe depends on the kernel for the kernel modules, and the kernel depends on the initramfs recipe since the initramfs is bundled inside the kernel image. The combined binary is deposited into the tmp/deploy directory, which is part of the Build Directory. Setting the variable to "1" in a configuration file causes the OpenEmbedded build system to generate a kernel image with the initramfs specified in INITRAMFS_IMAGE bundled within: INITRAMFS_IMAGE_BUNDLE = "1" By default, the kernel class sets this variable to a null string as follows: INITRAMFS_IMAGE_BUNDLE ?= "" You must set the INITRAMFS_IMAGE_BUNDLE variable in a configuration file. You cannot set the variable in a recipe file. See the local.conf.sample.extended file for additional information. Also, for information on creating an initramfs, see the "Building an Initial RAM Filesystem (initramfs) Image" section in the Yocto Project Development Manual. INITRD INITRD[doc] = "Indicates a list of filesystem images to concatenate and use as an initial RAM disk (initrd)." Indicates list of filesystem images to concatenate and use as an initial RAM disk (initrd). The INITRD variable is an optional variable used with the image-live class. INITRD_IMAGE INITRD_IMAGE[doc] = "When building a "live" bootable image (i.e. when IMAGE_FSTYPES contains "live"), INITRD_IMAGE specifies the image recipe that should be built to provide the initial RAM disk image." When building a "live" bootable image (i.e. when IMAGE_FSTYPES contains "live"), INITRD_IMAGE specifies the image recipe that should be built to provide the initial RAM disk image. The default value is "core-image-minimal-initramfs". See the image-live class for more information. INITSCRIPT_NAME INITSCRIPT_NAME[doc] = "The filename of the initialization script as installed to ${sysconfdir}/init.d." The filename of the initialization script as installed to ${sysconfdir}/init.d. This variable is used in recipes when using update-rc.d.bbclass. The variable is mandatory. INITSCRIPT_PACKAGES INITSCRIPT_PACKAGES[doc] = "A list of the packages that contain initscripts. This variable is used in recipes when using update-rc.d.bbclass. The variable is optional and defaults to the PN variable." A list of the packages that contain initscripts. If multiple packages are specified, you need to append the package name to the other INITSCRIPT_* as an override. This variable is used in recipes when using update-rc.d.bbclass. The variable is optional and defaults to the PN variable. INITSCRIPT_PARAMS INITSCRIPT_PARAMS[doc] = "Specifies the options to pass to update-rc.d. The variable is mandatory and is used in recipes when using update-rc.d.bbclass." Specifies the options to pass to update-rc.d. Here is an example: INITSCRIPT_PARAMS = "start 99 5 2 . stop 20 0 1 6 ." In this example, the script has a runlevel of 99, starts the script in initlevels 2 and 5, and stops the script in levels 0, 1 and 6. The variable's default value is "defaults", which is set in the update-rc.d class. The value in INITSCRIPT_PARAMS is passed through to the update-rc.d command. For more information on valid parameters, please see the update-rc.d manual page at . INSANE_SKIP INSANE_SKIP[doc] = "Specifies the QA checks to skip for a specific package within a recipe." Specifies the QA checks to skip for a specific package within a recipe. For example, to skip the check for symbolic link .so files in the main package of a recipe, add the following to the recipe. The package name override must be used, which in this example is ${PN}: INSANE_SKIP_${PN} += "dev-so" See the "insane.bbclass" section for a list of the valid QA checks you can specify using this variable. INSTALL_TIMEZONE_FILE INSTALL_TIMEZONE_FILE[doc] = "Enables installation of the /etc/timezone file." By default, the tzdata recipe packages an /etc/timezone file. Set the INSTALL_TIMEZONE_FILE variable to "0" at the configuration level to disable this behavior. IPK_FEED_URIS IPK_FEED_URIS[doc] = "List of ipkg feed records to put into generated image." When the IPK backend is in use and package management is enabled on the target, you can use this variable to set up opkg in the target image to point to package feeds on a nominated server. Once the feed is established, you can perform installations or upgrades using the package manager at runtime. KARCH KARCH[doc] = "Defines the kernel architecture used when assembling the configuration. You define the KARCH variable in the BSP Descriptions." Defines the kernel architecture used when assembling the configuration. Architectures supported for this release are: powerpc i386 x86_64 arm qemu mips You define the KARCH variable in the BSP Descriptions. KBRANCH KBRANCH[doc] = "A regular expression used by the build process to explicitly identify the kernel branch that is validated, patched and configured during a build." A regular expression used by the build process to explicitly identify the kernel branch that is validated, patched, and configured during a build. You must set this variable to ensure the exact kernel branch you want is being used by the build process. Values for this variable are set in the kernel's recipe file and the kernel's append file. For example, if you are using the Yocto Project kernel that is based on the Linux 3.14 kernel, the kernel recipe file is the meta/recipes-kernel/linux/linux-yocto_3.14.bb file. Following is an example for a kernel recipe file: KBRANCH ?= "standard/base" This variable is also used from the kernel's append file to identify the kernel branch specific to a particular machine or target hardware. The kernel's append file is located in the BSP layer for a given machine. For example, the kernel append file for the Emenlow BSP is in the meta-intel Git repository and is named meta-emenlow/recipes-kernel/linux/linux-yocto_3.14.bbappend. Here are the related statements from the append file: COMPATIBLE_MACHINE_emenlow-noemgd = "emenlow-noemgd" KMACHINE_emenlow-noemgd = "emenlow" KBRANCH_emenlow-noemgd = "standard/base" KERNEL_FEATURES_append_emenlow-noemgd = " features/drm-gma500/drm-gma500.scc" The KBRANCH statement identifies the kernel branch to use when building for the Emenlow BSP. KBUILD_DEFCONFIG KBUILD_DEFCONFIG[doc] = "Specifies an "in-tree" kernel configuration file for use during a kernel build." When used with the kernel-yocto class, specifies an "in-tree" kernel configuration file for use during a kernel build. Typically, when using a defconfig to configure a kernel during a build, you place the file in your layer in the same manner as you would patch files and configuration fragment files (i.e. "out-of-tree"). However, if you want to use a defconfig file that is part of the kernel tree (i.e. "in-tree"), you can use the KBUILD_DEFCONFIG variable to point to the defconfig file. To use the variable, set it in the append file for your kernel recipe using the following form: KBUILD_DEFCONFIG_KMACHINE ?= defconfig_file Here is an example from a "raspberrypi2" KMACHINE build that uses a defconfig file named "bcm2709_defconfig": KBUILD_DEFCONFIG_raspberrypi2 = "bcm2709_defconfig" As an alternative, you can use the following within your append file: KBUILD_DEFCONFIG_pn-linux-yocto ?= defconfig_file For more information on how to use the KBUILD_DEFCONFIG variable, see the "Using an "In-Tree" defconfig File" section. KERNEL_ALT_IMAGETYPE KERNEL_ALT_IMAGETYPE[doc] = "Specifies an alternate kernel image type for creation." Specifies an alternate kernel image type for creation in addition to the kernel image type specified using the KERNEL_IMAGETYPE variable. KERNEL_CLASSES KERNEL_CLASSES[doc] = "A list of classes defining kernel image types that kernel class should inherit." A list of classes defining kernel image types that the kernel class should inherit. You typically append this variable to enable extended image types. An example is the "kernel-fitimage", which enables fitImage support and resides in meta/classes/kernel-fitimage.bbclass. You can register custom kernel image types with the kernel class using this variable. KERNEL_DEVICETREE KERNEL_DEVICETREE[doc] = "Specifies the name of the generated Linux kernel device tree (i.e. the .dtb) file." Specifies the name of the generated Linux kernel device tree (i.e. the .dtb) file. Legacy support exists for specifying the full path to the device tree. However, providing just the .dtb file is preferred. In order to use this variable, you must have the include files in your kernel recipe: require recipes-kernel/linux/linux-dtb.inc or require recipes-kernel/linux/linux-yocto.inc KERNEL_EXTRA_ARGS KERNEL_EXTRA_ARGS[doc] = "Specifies additional make command-line arguments the OpenEmbedded build system passes on when compiling the kernel." Specifies additional make command-line arguments the OpenEmbedded build system passes on when compiling the kernel. KERNEL_FEATURES KERNEL_FEATURES[doc] = "Includes additional metadata from the Yocto Project kernel Git repository. The metadata you add through this variable includes config fragments and features descriptions." Includes additional metadata from the Yocto Project kernel Git repository. In the OpenEmbedded build system, the default Board Support Packages (BSPs) Metadata is provided through the KMACHINE and KBRANCH variables. You can use the KERNEL_FEATURES variable to further add metadata for all BSPs. The metadata you add through this variable includes config fragments and features descriptions, which usually includes patches as well as config fragments. You typically override the KERNEL_FEATURES variable for a specific machine. In this way, you can provide validated, but optional, sets of kernel configurations and features. For example, the following adds netfilter to all the Yocto Project kernels and adds sound support to the qemux86 machine: # Add netfilter to all linux-yocto kernels KERNEL_FEATURES="features/netfilter/netfilter.scc" # Add sound support to the qemux86 machine KERNEL_FEATURES_append_qemux86=" cfg/sound.scc" KERNEL_IMAGE_BASE_NAME KERNEL_IMAGE_BASE_NAME[doc] = "The base name of the kernel image." The base name of the kernel image. This variable is set in the kernel class as follows: KERNEL_IMAGE_BASE_NAME ?= "${PKGE}-${PKGV}-${PKGR}-${MACHINE}-${DATETIME}" See the PKGE, PKGV, PKGR, MACHINE, and DATETIME variables for additional information. KERNEL_IMAGE_MAXSIZE KERNEL_IMAGE_MAXSIZE[doc] = "The maximum allowable size in kilobytes of the kernel image file." Specifies the maximum size of the kernel image file in kilobytes. If KERNEL_IMAGE_MAXSIZE is set, the size of the kernel image file is checked against the set value during the do_sizecheck task. The task fails if the kernel image file is larger than the setting. KERNEL_IMAGE_MAXSIZE is useful for target devices that have a limited amount of space in which the kernel image must be stored. By default, this variable is not set, which means the size of the kernel image is not checked. KERNEL_IMAGETYPE KERNEL_IMAGETYPE[doc] = "The type of kernel to build for a device, usually set by the machine configuration files and defaults to 'zImage'." The type of kernel to build for a device, usually set by the machine configuration files and defaults to "zImage". This variable is used when building the kernel and is passed to make as the target to build. If you want to build an alternate kernel image type, use the KERNEL_ALT_IMAGETYPE variable. KERNEL_MODULE_AUTOLOAD KERNEL_MODULE_AUTOLOAD[doc] = "Lists kernel modules that need to be auto-loaded during boot" Lists kernel modules that need to be auto-loaded during boot. This variable replaces the deprecated module_autoload variable. You can use the KERNEL_MODULE_AUTOLOAD variable anywhere that it can be recognized by the kernel recipe or by an out-of-tree kernel module recipe (e.g. a machine configuration file, a distribution configuration file, an append file for the recipe, or the recipe itself). Specify it as follows: KERNEL_MODULE_AUTOLOAD += "module_name1 module_name2 module_name3" Including KERNEL_MODULE_AUTOLOAD causes the OpenEmbedded build system to populate the /etc/modules-load.d/modname.conf file with the list of modules to be auto-loaded on boot. The modules appear one-per-line in the file. Here is an example of the most common use case: KERNEL_MODULE_AUTOLOAD += "module_name" For information on how to populate the modname.conf file with modprobe.d syntax lines, see the KERNEL_MODULE_PROBECONF variable. KERNEL_MODULE_PROBECONF KERNEL_MODULE_PROBECONF[doc] = "Lists kernel modules for which the build system expects to find module_conf_* values that specify configuration for each of the modules." Provides a list of modules for which the OpenEmbedded build system expects to find module_conf_modname values that specify configuration for each of the modules. For information on how to provide those module configurations, see the module_conf_* variable. KERNEL_PATH KERNEL_PATH[doc] = "The location of the kernel sources. This variable is set to the value of the STAGING_KERNEL_DIR within the module class (module.bbclass)." The location of the kernel sources. This variable is set to the value of the STAGING_KERNEL_DIR within the module class. For information on how this variable is used, see the "Incorporating Out-of-Tree Modules" section. To help maximize compatibility with out-of-tree drivers used to build modules, the OpenEmbedded build system also recognizes and uses the KERNEL_SRC variable, which is identical to the KERNEL_PATH variable. Both variables are common variables used by external Makefiles to point to the kernel source directory. KERNEL_SRC KERNEL_SRC[doc] = "The location of the kernel sources. This variable is set to the value of the STAGING_KERNEL_DIR within the module class (module.bbclass)." The location of the kernel sources. This variable is set to the value of the STAGING_KERNEL_DIR within the module class. For information on how this variable is used, see the "Incorporating Out-of-Tree Modules" section. To help maximize compatibility with out-of-tree drivers used to build modules, the OpenEmbedded build system also recognizes and uses the KERNEL_PATH variable, which is identical to the KERNEL_SRC variable. Both variables are common variables used by external Makefiles to point to the kernel source directory. KERNEL_VERSION KERNEL_VERSION[doc] = "Specifies the version of the kernel as extracted from version.h or utsrelease.h within the kernel sources." Specifies the version of the kernel as extracted from version.h or utsrelease.h within the kernel sources. Effects of setting this variable do not take affect until the kernel has been configured. Consequently, attempting to refer to this variable in contexts prior to configuration will not work. KERNELDEPMODDEPEND KERNELDEPMODDEPEND[doc] = "Specifies whether or not to use the data referenced through the PKGDATA_DIR directory." Specifies whether the data referenced through PKGDATA_DIR is needed or not. The KERNELDEPMODDEPEND does not control whether or not that data exists, but simply whether or not it is used. If you do not need to use the data, set the KERNELDEPMODDEPEND variable in your initramfs recipe. Setting the variable there when the data is not needed avoids a potential dependency loop. KFEATURE_DESCRIPTION KFEATURE_DESCRIPTION[doc] = "Provides a short description of a configuration fragment. You use this variable in the .scc file that describes a configuration fragment file." Provides a short description of a configuration fragment. You use this variable in the .scc file that describes a configuration fragment file. Here is the variable used in a file named smp.scc to describe SMP being enabled: define KFEATURE_DESCRIPTION "Enable SMP" KMACHINE KMACHINE[doc] = "The machine as known by the kernel." The machine as known by the kernel. Sometimes the machine name used by the kernel does not match the machine name used by the OpenEmbedded build system. For example, the machine name that the OpenEmbedded build system understands as core2-32-intel-common goes by a different name in the Linux Yocto kernel. The kernel understands that machine as intel-core2-32. For cases like these, the KMACHINE variable maps the kernel machine name to the OpenEmbedded build system machine name. These mappings between different names occur in the Yocto Linux Kernel's meta branch. As an example take a look in the common/recipes-kernel/linux/linux-yocto_3.19.bbappend file: LINUX_VERSION_core2-32-intel-common = "3.19.0" COMPATIBLE_MACHINE_core2-32-intel-common = "${MACHINE}" SRCREV_meta_core2-32-intel-common = "8897ef68b30e7426bc1d39895e71fb155d694974" SRCREV_machine_core2-32-intel-common = "43b9eced9ba8a57add36af07736344dcc383f711" KMACHINE_core2-32-intel-common = "intel-core2-32" KBRANCH_core2-32-intel-common = "standard/base" KERNEL_FEATURES_append_core2-32-intel-common = "${KERNEL_FEATURES_INTEL_COMMON}" The KMACHINE statement says that the kernel understands the machine name as "intel-core2-32". However, the OpenEmbedded build system understands the machine as "core2-32-intel-common". KTYPE KTYPE[doc] = "Defines the kernel type to be used in assembling the configuration." Defines the kernel type to be used in assembling the configuration. The linux-yocto recipes define "standard", "tiny", and "preempt-rt" kernel types. See the "Kernel Types" section in the Yocto Project Linux Kernel Development Manual for more information on kernel types. You define the KTYPE variable in the BSP Descriptions. The value you use must match the value used for the LINUX_KERNEL_TYPE value used by the kernel recipe. LABELS LABELS[doc] = "Provides a list of targets for automatic configuration." Provides a list of targets for automatic configuration. See the grub-efi class for more information on how this variable is used. LAYERDEPENDS LAYERDEPENDS[doc] = "Lists the layers, separated by spaces, on which this recipe depends. This variable is used in the conf/layer.conf file and must be suffixed with the name of the specific layer." Lists the layers, separated by spaces, on which this recipe depends. Optionally, you can specify a specific layer version for a dependency by adding it to the end of the layer name. Here is an example: LAYERDEPENDS_mylayer = "anotherlayer (=3)" In this previous example, version 3 of "anotherlayer" is compared against LAYERVERSION_anotherlayer. An error is produced if any dependency is missing or the version numbers (if specified) do not match exactly. This variable is used in the conf/layer.conf file and must be suffixed with the name of the specific layer (e.g. LAYERDEPENDS_mylayer). LAYERDIR LAYERDIR[doc] = "When used inside the layer.conf configuration file, this variable provides the path of the current layer." When used inside the layer.conf configuration file, this variable provides the path of the current layer. This variable is not available outside of layer.conf and references are expanded immediately when parsing of the file completes. LAYERRECOMMENDS LAYERRECOMMENDS[doc] = "Lists the layers, separated by spaces, recommended for use with this layer." Lists the layers, separated by spaces, recommended for use with this layer. Optionally, you can specify a specific layer version for a recommendation by adding the version to the end of the layer name. Here is an example: LAYERRECOMMENDS_mylayer = "anotherlayer (=3)" In this previous example, version 3 of "anotherlayer" is compared against LAYERVERSION_anotherlayer. An error is produced if any dependency is missing or the version numbers (if specified) do not match exactly. This variable is used in the conf/layer.conf file and must be suffixed with the name of the specific layer (e.g. LAYERRECOMMENDS_mylayer). LAYERVERSION LAYERVERSION[doc] = "Optionally specifies the version of a layer as a single number. This variable is used in the conf/layer.conf file and must be suffixed with the name of the specific layer." Optionally specifies the version of a layer as a single number. You can use this within LAYERDEPENDS for another layer in order to depend on a specific version of the layer. This variable is used in the conf/layer.conf file and must be suffixed with the name of the specific layer (e.g. LAYERVERSION_mylayer). LD LD[doc] = "Minimal command and arguments to run the linker." The minimal command and arguments used to run the linker. LDFLAGS LDFLAGS[doc] = "Specifies the flags to pass to the linker." Specifies the flags to pass to the linker. This variable is exported to an environment variable and thus made visible to the software being built during the compilation step. Default initialization for LDFLAGS varies depending on what is being built: TARGET_LDFLAGS when building for the target BUILD_LDFLAGS when building for the build host (i.e. -native) BUILDSDK_LDFLAGS when building for an SDK (i.e. nativesdk-) LEAD_SONAME LEAD_SONAME[doc] = "Specifies the lead (or primary) compiled library file (.so) that the debian class applies its naming policy to given a recipe that packages multiple libraries." Specifies the lead (or primary) compiled library file (.so) that the debian class applies its naming policy to given a recipe that packages multiple libraries. This variable works in conjunction with the debian class. LIC_FILES_CHKSUM LIC_FILES_CHKSUM[doc] = "Checksums of the license text in the recipe source code." Checksums of the license text in the recipe source code. This variable tracks changes in license text of the source code files. If the license text is changed, it will trigger a build failure, which gives the developer an opportunity to review any license change. This variable must be defined for all recipes (unless LICENSE is set to "CLOSED"). For more information, see the " Tracking License Changes" section. LICENSE LICENSE[doc] = "The list of source licenses for the recipe. The logical operators &, '|', and parentheses can be used." The list of source licenses for the recipe. Follow these rules: Do not use spaces within individual license names. Separate license names using | (pipe) when there is a choice between licenses. Separate license names using & (ampersand) when multiple licenses exist that cover different parts of the source. You can use spaces between license names. For standard licenses, use the names of the files in meta/files/common-licenses/ or the SPDXLICENSEMAP flag names defined in meta/conf/licenses.conf. Here are some examples: LICENSE = "LGPLv2.1 | GPLv3" LICENSE = "MPL-1 & LGPLv2.1" LICENSE = "GPLv2+" The first example is from the recipes for Qt, which the user may choose to distribute under either the LGPL version 2.1 or GPL version 3. The second example is from Cairo where two licenses cover different parts of the source code. The final example is from sysstat, which presents a single license. You can also specify licenses on a per-package basis to handle situations where components of the output have different licenses. For example, a piece of software whose code is licensed under GPLv2 but has accompanying documentation licensed under the GNU Free Documentation License 1.2 could be specified as follows: LICENSE = "GFDL-1.2 & GPLv2" LICENSE_${PN} = "GPLv2" LICENSE_${PN}-doc = "GFDL-1.2" LICENSE_CREATE_PACKAGE LICENSE_CREATE_PACKAGE[doc] = "Creates an extra package (i.e. ${PN}-lic) for each recipe and adds that package to the RRECOMMENDS+${PN}." Setting LICENSE_CREATE_PACKAGE to "1" causes the OpenEmbedded build system to create an extra package (i.e. ${PN}-lic) for each recipe and to add those packages to the RRECOMMENDS_${PN}. The ${PN}-lic package installs a directory in /usr/share/licenses named ${PN}, which is the recipe's base name, and installs files in that directory that contain license and copyright information (i.e. copies of the appropriate license files from meta/common-licenses that match the licenses specified in the LICENSE variable of the recipe metadata and copies of files marked in LIC_FILES_CHKSUM as containing license text). For related information on providing license text, see the COPY_LIC_DIRS variable, the COPY_LIC_MANIFEST variable, and the "Providing License Text" section in the Yocto Project Development Manual. LICENSE_FLAGS LICENSE_FLAGS[doc] = "Specifies additional flags for a recipe you must whitelist through LICENSE_FLAGS_WHITELIST in order to allow the recipe to be built." Specifies additional flags for a recipe you must whitelist through LICENSE_FLAGS_WHITELIST in order to allow the recipe to be built. When providing multiple flags, separate them with spaces. This value is independent of LICENSE and is typically used to mark recipes that might require additional licenses in order to be used in a commercial product. For more information, see the "Enabling Commercially Licensed Recipes" section. LICENSE_FLAGS_WHITELIST LICENSE_FLAGS_WHITELIST[doc] = "Lists license flags that when specified in LICENSE_FLAGS within a recipe should not prevent that recipe from being built." Lists license flags that when specified in LICENSE_FLAGS within a recipe should not prevent that recipe from being built. This practice is otherwise known as "whitelisting" license flags. For more information, see the Enabling Commercially Licensed Recipes" section. LICENSE_PATH LICENSE_PATH[doc] = "Path to additional licenses used during the build." Path to additional licenses used during the build. By default, the OpenEmbedded build system uses COMMON_LICENSE_DIR to define the directory that holds common license text used during the build. The LICENSE_PATH variable allows you to extend that location to other areas that have additional licenses: LICENSE_PATH += "path-to-additional-common-licenses" LINUX_KERNEL_TYPE LINUX_KERNEL_TYPE[doc] = "Defines the kernel type to be used in assembling the configuration." Defines the kernel type to be used in assembling the configuration. The linux-yocto recipes define "standard", "tiny", and "preempt-rt" kernel types. See the "Kernel Types" section in the Yocto Project Linux Kernel Development Manual for more information on kernel types. If you do not specify a LINUX_KERNEL_TYPE, it defaults to "standard". Together with KMACHINE, the LINUX_KERNEL_TYPE variable defines the search arguments used by the kernel tools to find the appropriate description within the kernel Metadata with which to build out the sources and configuration. LINUX_VERSION LINUX_VERSION[doc] = "The Linux version from kernel.org on which the Linux kernel image being built using the OpenEmbedded build system is based. You define this variable in the kernel recipe." The Linux version from kernel.org on which the Linux kernel image being built using the OpenEmbedded build system is based. You define this variable in the kernel recipe. For example, the linux-yocto-3.4.bb kernel recipe found in meta/recipes-kernel/linux defines the variables as follows: LINUX_VERSION ?= "3.4.24" The LINUX_VERSION variable is used to define PV for the recipe: PV = "${LINUX_VERSION}+git${SRCPV}" LINUX_VERSION_EXTENSION LINUX_VERSION_EXTENSION[doc] = "A string extension compiled into the version string of the Linux kernel built with the OpenEmbedded build system. You define this variable in the kernel recipe." A string extension compiled into the version string of the Linux kernel built with the OpenEmbedded build system. You define this variable in the kernel recipe. For example, the linux-yocto kernel recipes all define the variable as follows: LINUX_VERSION_EXTENSION ?= "-yocto-${LINUX_KERNEL_TYPE}" Defining this variable essentially sets the Linux kernel configuration item CONFIG_LOCALVERSION, which is visible through the uname command. Here is an example that shows the extension assuming it was set as previously shown: $ uname -r 3.7.0-rc8-custom LOG_DIR LOG_DIR[doc] = "Specifies the directory to which the OpenEmbedded build system writes overall log files. The default directory is ${TMPDIR}/log" Specifies the directory to which the OpenEmbedded build system writes overall log files. The default directory is ${TMPDIR}/log. For the directory containing logs specific to each task, see the T variable. MACHINE MACHINE[doc] = "Specifies the target device for which the image is built. You define MACHINE in the conf/local.conf file in the Build Directory." Specifies the target device for which the image is built. You define MACHINE in the local.conf file found in the Build Directory. By default, MACHINE is set to "qemux86", which is an x86-based architecture machine to be emulated using QEMU: MACHINE ?= "qemux86" The variable corresponds to a machine configuration file of the same name, through which machine-specific configurations are set. Thus, when MACHINE is set to "qemux86" there exists the corresponding qemux86.conf machine configuration file, which can be found in the Source Directory in meta/conf/machine. The list of machines supported by the Yocto Project as shipped include the following: MACHINE ?= "qemuarm" MACHINE ?= "qemuarm64" MACHINE ?= "qemumips" MACHINE ?= "qemumips64" MACHINE ?= "qemuppc" MACHINE ?= "qemux86" MACHINE ?= "qemux86-64" MACHINE ?= "genericx86" MACHINE ?= "genericx86-64" MACHINE ?= "beaglebone" MACHINE ?= "mpc8315e-rdb" MACHINE ?= "edgerouter" The last five are Yocto Project reference hardware boards, which are provided in the meta-yocto-bsp layer. Adding additional Board Support Package (BSP) layers to your configuration adds new possible settings for MACHINE. MACHINE_ARCH MACHINE_ARCH[doc] = "Specifies the name of the machine-specific architecture. This variable is set automatically from MACHINE or TUNE_PKGARCH." Specifies the name of the machine-specific architecture. This variable is set automatically from MACHINE or TUNE_PKGARCH. You should not hand-edit the MACHINE_ARCH variable. MACHINE_ESSENTIAL_EXTRA_RDEPENDS MACHINE_ESSENTIAL_EXTRA_RDEPENDS[doc] = "A list of required machine-specific packages to install as part of the image being built. Because this is a 'machine essential' variable, the list of packages are essential for the machine to boot." A list of required machine-specific packages to install as part of the image being built. The build process depends on these packages being present. Furthermore, because this is a "machine essential" variable, the list of packages are essential for the machine to boot. The impact of this variable affects images based on packagegroup-core-boot, including the core-image-minimal image. This variable is similar to the MACHINE_ESSENTIAL_EXTRA_RRECOMMENDS variable with the exception that the image being built has a build dependency on the variable's list of packages. In other words, the image will not build if a file in this list is not found. As an example, suppose the machine for which you are building requires example-init to be run during boot to initialize the hardware. In this case, you would use the following in the machine's .conf configuration file: MACHINE_ESSENTIAL_EXTRA_RDEPENDS += "example-init" MACHINE_ESSENTIAL_EXTRA_RRECOMMENDS MACHINE_ESSENTIAL_EXTRA_RRECOMMENDS[doc] = "A list of recommended machine-specific packages to install as part of the image being built. Because this is a 'machine essential' variable, the list of packages are essential for the machine to boot." A list of recommended machine-specific packages to install as part of the image being built. The build process does not depend on these packages being present. However, because this is a "machine essential" variable, the list of packages are essential for the machine to boot. The impact of this variable affects images based on packagegroup-core-boot, including the core-image-minimal image. This variable is similar to the MACHINE_ESSENTIAL_EXTRA_RDEPENDS variable with the exception that the image being built does not have a build dependency on the variable's list of packages. In other words, the image will still build if a package in this list is not found. Typically, this variable is used to handle essential kernel modules, whose functionality may be selected to be built into the kernel rather than as a module, in which case a package will not be produced. Consider an example where you have a custom kernel where a specific touchscreen driver is required for the machine to be usable. However, the driver can be built as a module or into the kernel depending on the kernel configuration. If the driver is built as a module, you want it to be installed. But, when the driver is built into the kernel, you still want the build to succeed. This variable sets up a "recommends" relationship so that in the latter case, the build will not fail due to the missing package. To accomplish this, assuming the package for the module was called kernel-module-ab123, you would use the following in the machine's .conf configuration file: MACHINE_ESSENTIAL_EXTRA_RRECOMMENDS += "kernel-module-ab123" In this example, the kernel-module-ab123 recipe needs to explicitly set its PACKAGES variable to ensure that BitBake does not use the kernel recipe's PACKAGES_DYNAMIC variable to satisfy the dependency. Some examples of these machine essentials are flash, screen, keyboard, mouse, or touchscreen drivers (depending on the machine). MACHINE_EXTRA_RDEPENDS MACHINE_EXTRA_RDEPENDS[doc] = "A list of machine-specific packages to install as part of the image being built that are not essential for the machine to boot. However, the build process for more fully-featured images depends on the packages being present." A list of machine-specific packages to install as part of the image being built that are not essential for the machine to boot. However, the build process for more fully-featured images depends on the packages being present. This variable affects all images based on packagegroup-base, which does not include the core-image-minimal or core-image-full-cmdline images. The variable is similar to the MACHINE_EXTRA_RRECOMMENDS variable with the exception that the image being built has a build dependency on the variable's list of packages. In other words, the image will not build if a file in this list is not found. An example is a machine that has WiFi capability but is not essential for the machine to boot the image. However, if you are building a more fully-featured image, you want to enable the WiFi. The package containing the firmware for the WiFi hardware is always expected to exist, so it is acceptable for the build process to depend upon finding the package. In this case, assuming the package for the firmware was called wifidriver-firmware, you would use the following in the .conf file for the machine: MACHINE_EXTRA_RDEPENDS += "wifidriver-firmware" MACHINE_EXTRA_RRECOMMENDS MACHINE_EXTRA_RRECOMMENDS[doc] = "A list of machine-specific packages to install as part of the image being built that are not essential for booting the machine. The image being built has no build dependencies on the packages in this list." A list of machine-specific packages to install as part of the image being built that are not essential for booting the machine. The image being built has no build dependency on this list of packages. This variable affects only images based on packagegroup-base, which does not include the core-image-minimal or core-image-full-cmdline images. This variable is similar to the MACHINE_EXTRA_RDEPENDS variable with the exception that the image being built does not have a build dependency on the variable's list of packages. In other words, the image will build if a file in this list is not found. An example is a machine that has WiFi capability but is not essential For the machine to boot the image. However, if you are building a more fully-featured image, you want to enable WiFi. In this case, the package containing the WiFi kernel module will not be produced if the WiFi driver is built into the kernel, in which case you still want the build to succeed instead of failing as a result of the package not being found. To accomplish this, assuming the package for the module was called kernel-module-examplewifi, you would use the following in the .conf file for the machine: MACHINE_EXTRA_RRECOMMENDS += "kernel-module-examplewifi" MACHINE_FEATURES MACHINE_FEATURES[doc] = "Specifies the list of hardware features the MACHINE supports." Specifies the list of hardware features the MACHINE is capable of supporting. For related information on enabling features, see the DISTRO_FEATURES, COMBINED_FEATURES, and IMAGE_FEATURES variables. For a list of hardware features supported by the Yocto Project as shipped, see the "Machine Features" section. MACHINE_FEATURES_BACKFILL MACHINE_FEATURES_BACKFILL[doc] = "Features to be added to MACHINE_FEATURES if not also present in MACHINE_FEATURES_BACKFILL_CONSIDERED. This variable is set in the meta/conf/bitbake.conf file and is not intended to be user-configurable." Features to be added to MACHINE_FEATURES if not also present in MACHINE_FEATURES_BACKFILL_CONSIDERED. This variable is set in the meta/conf/bitbake.conf file. It is not intended to be user-configurable. It is best to just reference the variable to see which machine features are being backfilled for all machine configurations. See the "Feature backfilling" section for more information. MACHINE_FEATURES_BACKFILL_CONSIDERED MACHINE_FEATURES_BACKFILL_CONSIDERED[doc] = "Features from MACHINE_FEATURES_BACKFILL that should not be backfilled (i.e. added to MACHINE_FEATURES) during the build." Features from MACHINE_FEATURES_BACKFILL that should not be backfilled (i.e. added to MACHINE_FEATURES) during the build. See the "Feature backfilling" section for more information. MACHINEOVERRIDES MACHINEOVERRIDES[doc] = "A colon-separated list of overrides that apply to the current machine." A colon-separated list of overrides that apply to the current machine. By default, this list includes the value of MACHINE. You can extend MACHINEOVERRIDES to add extra overrides that should apply to a machine. For example, all machines emulated in QEMU (e.g. qemuarm, qemux86, and so forth) include a file named meta/conf/machine/include/qemu.inc that prepends the following override to MACHINEOVERRIDES: MACHINEOVERRIDES =. "qemuall:" This override allows variables to be overriden for all machines emulated in QEMU, like in the following example from the connman-conf recipe: SRC_URI_append_qemuall = "file://wired.config \ file://wired-setup \ " The underlying mechanism behind MACHINEOVERRIDES is simply that it is included in the default value of OVERRIDES. MAINTAINER MAINTAINER[doc] = "The email address of the distribution maintainer." The email address of the distribution maintainer. MIRRORS MIRRORS[doc] = "Specifies additional paths from which the OpenEmbedded build system gets source code." Specifies additional paths from which the OpenEmbedded build system gets source code. When the build system searches for source code, it first tries the local download directory. If that location fails, the build system tries locations defined by PREMIRRORS, the upstream source, and then locations specified by MIRRORS in that order. Assuming your distribution (DISTRO) is "poky", the default value for MIRRORS is defined in the conf/distro/poky.conf file in the meta-poky Git repository. MLPREFIX MLPREFIX[doc] = "Specifies a prefix has been added to PN to create a special version of a recipe or package, such as a Multilib version." Specifies a prefix has been added to PN to create a special version of a recipe or package, such as a Multilib version. The variable is used in places where the prefix needs to be added to or removed from a the name (e.g. the BPN variable). MLPREFIX gets set when a prefix has been added to PN. The "ML" in MLPREFIX stands for "MultiLib". This representation is historical and comes from a time when nativesdk was a suffix rather than a prefix on the recipe name. When nativesdk was turned into a prefix, it made sense to set MLPREFIX for it as well. To help understand when MLPREFIX might be needed, consider when BBCLASSEXTEND is used to provide a nativesdk version of a recipe in addition to the target version. If that recipe declares build-time dependencies on tasks in other recipes by using DEPENDS, then a dependency on "foo" will automatically get rewritten to a dependency on "nativesdk-foo". However, dependencies like the following will not get rewritten automatically: do_foo[depends] += "recipe:do_foo" If you want such a dependency to also get transformed, you can do the following: do_foo[depends] += "${MLPREFIX}recipe:do_foo" module_autoload module_autoload[doc] = "This variable has been replaced by the KERNEL_MODULE_AUTOLOAD variable. You should replace all occurrences of module_autoload with additions to KERNEL_MODULE_AUTOLOAD." This variable has been replaced by the KERNEL_MODULE_AUTOLOAD variable. You should replace all occurrences of module_autoload with additions to KERNEL_MODULE_AUTOLOAD, for example: module_autoload_rfcomm = "rfcomm" should now be replaced with: KERNEL_MODULE_AUTOLOAD += "rfcomm" See the KERNEL_MODULE_AUTOLOAD variable for more information. module_conf module_conf[doc] = "Specifies modprobe.d syntax lines for inclusion in the /etc/modprobe.d/modname.conf file." Specifies modprobe.d syntax lines for inclusion in the /etc/modprobe.d/modname.conf file. You can use this variable anywhere that it can be recognized by the kernel recipe or out-of-tree kernel module recipe (e.g. a machine configuration file, a distribution configuration file, an append file for the recipe, or the recipe itself). If you use this variable, you must also be sure to list the module name in the KERNEL_MODULE_AUTOLOAD variable. Here is the general syntax: module_conf_module_name = "modprobe.d-syntax" You must use the kernel module name override. Run man modprobe.d in the shell to find out more information on the exact syntax you want to provide with module_conf. Including module_conf causes the OpenEmbedded build system to populate the /etc/modprobe.d/modname.conf file with modprobe.d syntax lines. Here is an example that adds the options arg1 and arg2 to a module named mymodule: module_conf_mymodule = "options mymodule arg1=val1 arg2=val2" For information on how to specify kernel modules to auto-load on boot, see the KERNEL_MODULE_AUTOLOAD variable. MODULE_IMAGE_BASE_NAME MODULE_IMAGE_BASE_NAME[doc] = "The base name of the kernel modules tarball." The base name of the kernel modules tarball. This variable is set in the kernel class as follows: MODULE_IMAGE_BASE_NAME ?= "modules-${PKGE}-${PKGV}-${PKGR}-${MACHINE}-${DATETIME}" See the PKGE, PKGV, PKGR, MACHINE, and DATETIME variables for additional information. MODULE_TARBALL_DEPLOY MODULE_TARBALL_DEPLOY[doc] = "Controls creation of the modules-*.tgz file. Set this variable to "0" to disable creation of this file, which contains all of the kernel modules resulting from a kernel build." Controls creation of the modules-*.tgz file. Set this variable to "0" to disable creation of this file, which contains all of the kernel modules resulting from a kernel build. MULTIMACH_TARGET_SYS MULTIMACH_TARGET_SYS[doc] = "Separates files for different machines such that you can build for multiple target machines using the same output directories." Uniquely identifies the type of the target system for which packages are being built. This variable allows output for different types of target systems to be put into different subdirectories of the same output directory. The default value of this variable is: ${PACKAGE_ARCH}${TARGET_VENDOR}-${TARGET_OS} Some classes (e.g. cross-canadian) modify the MULTIMACH_TARGET_SYS value. See the STAMP variable for an example. See the STAGING_DIR_TARGET variable for more information. NATIVELSBSTRING NATIVELSBSTRING[doc] = "A string identifying the host distribution." A string identifying the host distribution. Strings consist of the host distributor ID followed by the release, as reported by the lsb_release tool or as read from /etc/lsb-release. For example, when running a build on Ubuntu 12.10, the value is "Ubuntu-12.10". If this information is unable to be determined, the value resolves to "Unknown". This variable is used by default to isolate native shared state packages for different distributions (e.g. to avoid problems with glibc version incompatibilities). Additionally, the variable is checked against SANITY_TESTED_DISTROS if that variable is set. NM NM[doc] = "Minimal command and arguments to run 'nm'." The minimal command and arguments to run nm. NO_RECOMMENDATIONS NO_RECOMMENDATIONS[doc] = "When set to '1', no recommended packages will be installed. Realize that some recommended packages might be required for certain system functionality, such as kernel-modules. It is up to the user to add packages to IMAGE_INSTALL as needed." Prevents installation of all "recommended-only" packages. Recommended-only packages are packages installed only through the RRECOMMENDS variable). Setting the NO_RECOMMENDATIONS variable to "1" turns this feature on: NO_RECOMMENDATIONS = "1" You can set this variable globally in your local.conf file or you can attach it to a specific image recipe by using the recipe name override: NO_RECOMMENDATIONS_pn-target_image = "1" It is important to realize that if you choose to not install packages using this variable and some other packages are dependent on them (i.e. listed in a recipe's RDEPENDS variable), the OpenEmbedded build system ignores your request and will install the packages to avoid dependency errors. Some recommended packages might be required for certain system functionality, such as kernel modules. It is up to you to add packages with the IMAGE_INSTALL variable. Support for this variable exists only when using the IPK and RPM packaging backend. Support does not exist for DEB. See the BAD_RECOMMENDATIONS and the PACKAGE_EXCLUDE variables for related information. NOHDD NOHDD[doc] = "Causes the OpenEmbedded build system to skip building the .hddimg image." Causes the OpenEmbedded build system to skip building the .hddimg image. The NOHDD variable is used with the image-live class. Set the variable to "1" to prevent the .hddimg image from being built. NOISO NOISO[doc] = "Causes the OpenEmbedded build system to skip building the ISO image." Causes the OpenEmbedded build system to skip building the ISO image. The NOISO variable is used with the image-live class. Set the variable to "1" to prevent the ISO image from being built. To enable building an ISO image, set the variable to "0". OBJCOPY OBJCOPY[doc] = "Minimal command and arguments to run 'objcopy'." The minimal command and arguments to run objcopy. OBJDUMP OBJDUMP[doc] = "Minimal command and arguments to run 'objdump'." The minimal command and arguments to run objdump. OE_BINCONFIG_EXTRA_MANGLE OE_BINCONFIG_EXTRA_MANGLE[doc] = "When a recipe inherits the binconfig.bbclass class, this variable specifies additional arguments passed to the "sed" command." When inheriting the binconfig class, this variable specifies additional arguments passed to the "sed" command. The sed command alters any paths in configuration scripts that have been set up during compilation. Inheriting this class results in all paths in these scripts being changed to point into the sysroots/ directory so that all builds that use the script will use the correct directories for the cross compiling layout. See the meta/classes/binconfig.bbclass in the Source Directory for details on how this class applies these additional sed command arguments. For general information on the binconfig.bbclass class, see the "Binary Configuration Scripts - binconfig.bbclass" section. OE_IMPORTS OE_IMPORTS[doc] = "An internal variable used to tell the OpenEmbedded build system what Python modules to import for every Python function run by the system." An internal variable used to tell the OpenEmbedded build system what Python modules to import for every Python function run by the system. Do not set this variable. It is for internal use only. OE_INIT_ENV_SCRIPT OE_INIT_ENV_SCRIPT[doc] = "The name of the build environment setup script for the purposes of setting up the environment within the extensible SDK." The name of the build environment setup script for the purposes of setting up the environment within the extensible SDK. The default value is "oe-init-build-env". If you use a custom script to set up your build environment, set the OE_INIT_ENV_SCRIPT variable to its name. OE_TERMINAL OE_TERMINAL[doc] = "Controls how the OpenEmbedded build system spawns interactive terminals on the host development system." Controls how the OpenEmbedded build system spawns interactive terminals on the host development system (e.g. using the BitBake command with the -c devshell command-line option). For more information, see the "Using a Development Shell" section in the Yocto Project Development Manual. You can use the following values for the OE_TERMINAL variable: auto gnome xfce rxvt screen konsole none OEROOT OEROOT[doc] = "The directory from which the top-level build environment setup script is sourced." The directory from which the top-level build environment setup script is sourced. The Yocto Project makes two top-level build environment setup scripts available: &OE_INIT_FILE; and oe-init-build-env-memres. When you run one of these scripts, the OEROOT variable resolves to the directory that contains the script. For additional information on how this variable is used, see the initialization scripts. OLDEST_KERNEL OLDEST_KERNEL[doc] = "Declares the oldest version of the Linux kernel that the produced binaries must support." Declares the oldest version of the Linux kernel that the produced binaries must support. This variable is passed into the build of the Embedded GNU C Library (glibc). The default for this variable comes from the meta/conf/bitbake.conf configuration file. You can override this default by setting the variable in a custom distribution configuration file. OVERRIDES OVERRIDES[doc] = "A colon-separated list of overrides that currently apply." A colon-separated list of overrides that currently apply. Overrides are a BitBake mechanism that allows variables to be selectively overridden at the end of parsing. The set of overrides in OVERRIDES represents the "state" during building, which includes the current recipe being built, the machine for which it is being built, and so forth. As an example, if the string "an-override" appears as an element in the colon-separated list in OVERRIDES, then the following assignment will override FOO with the value "overridden" at the end of parsing: FOO_an-override = "overridden" See the "Conditional Syntax (Overrides)" section in the BitBake User Manual for more information on the overrides mechanism. The default value of OVERRIDES includes the values of the CLASSOVERRIDE, MACHINEOVERRIDES, and DISTROOVERRIDES variables. Another important override included by default is pn-${PN}. This override allows variables to be set for a single recipe within configuration (.conf) files. Here is an example: FOO_pn-myrecipe = "myrecipe-specific value" An easy way to see what overrides apply is to search for OVERRIDES in the output of the bitbake -e command. See the "Viewing Variable Values" section for more information. P P[doc] = "The recipe name and version. P is comprised of ${PN}-${PV}." The recipe name and version. P is comprised of the following: ${PN}-${PV} PACKAGE_ARCH PACKAGE_ARCH[doc] = "The architecture of the resulting package or packages." The architecture of the resulting package or packages. By default, the value of this variable is set to TUNE_PKGARCH when building for the target, BUILD_ARCH when building for the build host and "${SDK_ARCH}-${SDKPKGSUFFIX}" when building for the SDK. However, if your recipe's output packages are built specific to the target machine rather than general for the architecture of the machine, you should set PACKAGE_ARCH to the value of MACHINE_ARCH in the recipe as follows: PACKAGE_ARCH = "${MACHINE_ARCH}" PACKAGE_ARCHS PACKAGE_ARCHS[doc] = "A list of architectures compatible with the given target in order of priority." Specifies a list of architectures compatible with the target machine. This variable is set automatically and should not normally be hand-edited. Entries are separated using spaces and listed in order of priority. The default value for PACKAGE_ARCHS is "all any noarch ${PACKAGE_EXTRA_ARCHS} ${MACHINE_ARCH}". PACKAGE_BEFORE_PN PACKAGE_BEFORE_PN[doc] = "Enables easily adding packages to PACKAGES before ${PN} so that the packages can pick up files that would normally be included in the default package." Enables easily adding packages to PACKAGES before ${PN} so that those added packages can pick up files that would normally be included in the default package. PACKAGE_CLASSES PACKAGE_CLASSES[doc] = "This variable specifies the package manager to use when packaging data. It is set in the conf/local.conf file in the Build Directory." This variable, which is set in the local.conf configuration file found in the conf folder of the Build Directory, specifies the package manager the OpenEmbedded build system uses when packaging data. You can provide one or more of the following arguments for the variable: PACKAGE_CLASSES ?= "package_rpm package_deb package_ipk package_tar" While it is a legal option, the package_tar class is broken and is not supported. It is recommended that you do not use it. The build system uses only the first argument in the list as the package manager when creating your image or SDK. However, packages will be created using any additional packaging classes you specify. For example, if you use the following in your local.conf file: PACKAGE_CLASSES ?= "package_ipk" The OpenEmbedded build system uses the IPK package manager to create your image or SDK. For information on packaging and build performance effects as a result of the package manager in use, see the "package.bbclass" section. PACKAGE_DEBUG_SPLIT_STYLE PACKAGE_DEBUG_SPLIT_STYLE[doc] = "Determines how to split up the binary and debug information when creating *-dbg packages to be used with the GNU Project Debugger (GDB)." Determines how to split up the binary and debug information when creating *-dbg packages to be used with the GNU Project Debugger (GDB). With the PACKAGE_DEBUG_SPLIT_STYLE variable, you can control where debug information, which can include or exclude source files, is stored: ".debug": Debug symbol files are placed next to the binary in a .debug directory on the target. For example, if a binary is installed into /bin, the corresponding debug symbol files are installed in /bin/.debug. Source files are placed in /usr/src/debug. This is the default behavior. "debug-file-directory": Debug symbol files are placed under /usr/lib/debug on the target, and separated by the path from where the binary is installed. For example, if a binary is installed in /bin, the corresponding debug symbols are installed in /usr/lib/debug/bin. Source files are placed in /usr/src/debug. "debug-without-src": The same behavior as ".debug" previously described with the exception that no source files are installed. . You can find out more about debugging using GDB by reading the "Debugging With the GNU Project Debugger (GDB) Remotely" section in the Yocto Project Development Manual. PACKAGE_EXCLUDE_COMPLEMENTARY PACKAGE_EXCLUDE_COMPLEMENTARY[doc] = "Prevents specific packages from being installed when you are installing complementary packages." Prevents specific packages from being installed when you are installing complementary packages. You might find that you want to prevent installing certain packages when you are installing complementary packages. For example, if you are using IMAGE_FEATURES to install dev-pkgs, you might not want to install all packages from a particular multilib. If you find yourself in this situation, you can use the PACKAGE_EXCLUDE_COMPLEMENTARY variable to specify regular expressions to match the packages you want to exclude. PACKAGE_EXCLUDE PACKAGE_EXCLUDE[doc] = "Packages to exclude from the installation. If a listed package is required, an error is generated." Lists packages that should not be installed into an image. For example: PACKAGE_EXCLUDE = "package_name package_name package_name ..." You can set this variable globally in your local.conf file or you can attach it to a specific image recipe by using the recipe name override: PACKAGE_EXCLUDE_pn-target_image = "package_name" If you choose to not install a package using this variable and some other package is dependent on it (i.e. listed in a recipe's RDEPENDS variable), the OpenEmbedded build system generates a fatal installation error. Because the build system halts the process with a fatal error, you can use the variable with an iterative development process to remove specific components from a system. Support for this variable exists only when using the IPK and RPM packaging backend. Support does not exist for DEB. See the NO_RECOMMENDATIONS and the BAD_RECOMMENDATIONS variables for related information. PACKAGE_EXTRA_ARCHS PACKAGE_EXTRA_ARCHS[doc] = "Specifies the list of architectures compatible with the device CPU. This variable is useful when you build for several different devices that use miscellaneous processors." Specifies the list of architectures compatible with the device CPU. This variable is useful when you build for several different devices that use miscellaneous processors such as XScale and ARM926-EJS. PACKAGE_FEED_ARCHS PACKAGE_FEED_ARCHS[doc] = "Specifies user-defined package architectures when constructing package feed URIs." Specifies the package architectures used as part of the package feed URIs during the build. The PACKAGE_FEED_ARCHS variable is appended to the final package feed URI, which is constructed using the PACKAGE_FEED_URIS and PACKAGE_FEED_BASE_PATHS variables. Consider the following example where the PACKAGE_FEED_URIS, PACKAGE_FEED_BASE_PATHS, and PACKAGE_FEED_ARCHS variables are defined in your local.conf file: PACKAGE_FEED_URIS = "https://example.com/packagerepos/release \ https://example.com/packagerepos/updates" PACKAGE_FEED_BASE_PATHS = "rpm rpm-dev" PACKAGE_FEED_ARCHS = "all core2-64" Given these settings, the resulting package feeds are as follows: https://example.com/packagerepos/release/rpm/all https://example.com/packagerepos/release/rpm/core2-64 https://example.com/packagerepos/release/rpm-dev/all https://example.com/packagerepos/release/rpm-dev/core2-64 https://example.com/packagerepos/updates/rpm/all https://example.com/packagerepos/updates/rpm/core2-64 https://example.com/packagerepos/updates/rpm-dev/all https://example.com/packagerepos/updates/rpm-dev/core2-64 PACKAGE_FEED_BASE_PATHS PACKAGE_FEED_BASE_PATHS[doc] = "Specifies base path used when constructing package feed URIs." Specifies the base path used when constructing package feed URIs. The PACKAGE_FEED_BASE_PATHS variable makes up the middle portion of a package feed URI used by the OpenEmbedded build system. The base path lies between the PACKAGE_FEED_URIS and PACKAGE_FEED_ARCHS variables. Consider the following example where the PACKAGE_FEED_URIS, PACKAGE_FEED_BASE_PATHS, and PACKAGE_FEED_ARCHS variables are defined in your local.conf file: PACKAGE_FEED_URIS = "https://example.com/packagerepos/release \ https://example.com/packagerepos/updates" PACKAGE_FEED_BASE_PATHS = "rpm rpm-dev" PACKAGE_FEED_ARCHS = "all core2-64" Given these settings, the resulting package feeds are as follows: https://example.com/packagerepos/release/rpm/all https://example.com/packagerepos/release/rpm/core2-64 https://example.com/packagerepos/release/rpm-dev/all https://example.com/packagerepos/release/rpm-dev/core2-64 https://example.com/packagerepos/updates/rpm/all https://example.com/packagerepos/updates/rpm/core2-64 https://example.com/packagerepos/updates/rpm-dev/all https://example.com/packagerepos/updates/rpm-dev/core2-64 PACKAGE_FEED_URIS PACKAGE_FEED_URIS[doc] = "Specifies the front portion of the package feed URI used by the OpenEmbedded build system." Specifies the front portion of the package feed URI used by the OpenEmbedded build system. Each final package feed URI is comprised of PACKAGE_FEED_URIS, PACKAGE_FEED_BASE_PATHS, and PACKAGE_FEED_ARCHS variables. Consider the following example where the PACKAGE_FEED_URIS, PACKAGE_FEED_BASE_PATHS, and PACKAGE_FEED_ARCHS variables are defined in your local.conf file: PACKAGE_FEED_URIS = "https://example.com/packagerepos/release \ https://example.com/packagerepos/updates" PACKAGE_FEED_BASE_PATHS = "rpm rpm-dev" PACKAGE_FEED_ARCHS = "all core2-64" Given these settings, the resulting package feeds are as follows: https://example.com/packagerepos/release/rpm/all https://example.com/packagerepos/release/rpm/core2-64 https://example.com/packagerepos/release/rpm-dev/all https://example.com/packagerepos/release/rpm-dev/core2-64 https://example.com/packagerepos/updates/rpm/all https://example.com/packagerepos/updates/rpm/core2-64 https://example.com/packagerepos/updates/rpm-dev/all https://example.com/packagerepos/updates/rpm-dev/core2-64 PACKAGE_GROUP PACKAGE_GROUP[doc] = "Defines one or more packages to include in an image when a specific item is included in IMAGE_FEATURES." The PACKAGE_GROUP variable has been renamed to FEATURE_PACKAGES. See the variable description for FEATURE_PACKAGES for information. If if you use the PACKAGE_GROUP variable, the OpenEmbedded build system issues a warning message. PACKAGE_INSTALL PACKAGE_INSTALL[doc] = "List of the packages to be installed into the image. The variable is generally not user-defined and uses IMAGE_INSTALL as part of the list." The final list of packages passed to the package manager for installation into the image. Because the package manager controls actual installation of all packages, the list of packages passed using PACKAGE_INSTALL is not the final list of packages that are actually installed. This variable is internal to the image construction code. Consequently, in general, you should use the IMAGE_INSTALL variable to specify packages for installation. The exception to this is when working with the core-image-minimal-initramfs image. When working with an initial RAM filesystem (initramfs) image, use the PACKAGE_INSTALL variable. For information on creating an initramfs, see the "Building an Initial RAM Filesystem (initramfs) Image" section in the Yocto Project Development Manual. PACKAGE_INSTALL_ATTEMPTONLY PACKAGE_INSTALL_ATTEMPTONLY[doc] = "List of packages attempted to be installed when creating an image. If a listed package fails to install, the build system does not generate an error. This variable is generally not user-defined." Specifies a list of packages the OpenEmbedded build system attempts to install when creating an image. If a listed package fails to install, the build system does not generate an error. This variable is generally not user-defined. PACKAGE_PREPROCESS_FUNCS PACKAGE_PREPROCESS_FUNCS[doc] = "Specifies a list of functions run to pre-process the PKGD directory prior to splitting the files out to individual packages." Specifies a list of functions run to pre-process the PKGD directory prior to splitting the files out to individual packages. PACKAGE_WRITE_DEPS PACKAGE_WRITE_DEPS[doc] = "Specifies post-installation and pre-installation script dependencies on native/cross tools." Specifies a list of dependencies for post-installation and pre-installation scripts on native/cross tools. If your post-installation or pre-installation script can execute at rootfs creation time rather than on the target but depends on a native tool in order to execute, you need to list the tools in PACKAGE_WRITE_DEPENDS. For information on running post-installation scripts, see the "Post-Installation Scripts" section in the Yocto Project Development Manual. PACKAGECONFIG PACKAGECONFIG[doc] = "This variable provides a means of enabling or disabling features of a recipe on a per-recipe basis." This variable provides a means of enabling or disabling features of a recipe on a per-recipe basis. PACKAGECONFIG blocks are defined in recipes when you specify features and then arguments that define feature behaviors. Here is the basic block structure: PACKAGECONFIG ??= "f1 f2 f3 ..." PACKAGECONFIG[f1] = "--with-f1,--without-f1,build-deps-f1,rt-deps-f1" PACKAGECONFIG[f2] = "--with-f2,--without-f2,build-deps-f2,rt-deps-f2" PACKAGECONFIG[f3] = "--with-f3,--without-f3,build-deps-f3,rt-deps-f3" The PACKAGECONFIG variable itself specifies a space-separated list of the features to enable. Following the features, you can determine the behavior of each feature by providing up to four order-dependent arguments, which are separated by commas. You can omit any argument you like but must retain the separating commas. The order is important and specifies the following: Extra arguments that should be added to the configure script argument list (EXTRA_OECONF or PACKAGECONFIG_CONFARGS) if the feature is enabled. Extra arguments that should be added to EXTRA_OECONF or PACKAGECONFIG_CONFARGS if the feature is disabled. Additional build dependencies (DEPENDS) that should be added if the feature is enabled. Additional runtime dependencies (RDEPENDS) that should be added if the feature is enabled. Consider the following PACKAGECONFIG block taken from the librsvg recipe. In this example the feature is croco, which has three arguments that determine the feature's behavior. PACKAGECONFIG ??= "croco" PACKAGECONFIG[croco] = "--with-croco,--without-croco,libcroco" The --with-croco and libcroco arguments apply only if the feature is enabled. In this case, --with-croco is added to the configure script argument list and libcroco is added to DEPENDS. On the other hand, if the feature is disabled say through a .bbappend file in another layer, then the second argument --without-croco is added to the configure script rather than --with-croco. The basic PACKAGECONFIG structure previously described holds true regardless of whether you are creating a block or changing a block. When creating a block, use the structure inside your recipe. If you want to change an existing PACKAGECONFIG block, you can do so one of two ways: Append file: Create an append file named recipename.bbappend in your layer and override the value of PACKAGECONFIG. You can either completely override the variable: PACKAGECONFIG="f4 f5" Or, you can just append the variable: PACKAGECONFIG_append = " f4" Configuration file: This method is identical to changing the block through an append file except you edit your local.conf or mydistro.conf file. As with append files previously described, you can either completely override the variable: PACKAGECONFIG_pn-recipename="f4 f5" Or, you can just amend the variable: PACKAGECONFIG_append_pn-recipename = " f4" PACKAGECONFIG_CONFARGS PACKAGECONFIG_CONFARGS[doc] = "A space-separated list of configuration options generated from PACKAGECONFIG." A space-separated list of configuration options generated from the PACKAGECONFIG setting. This list of options helps other classes and recipes take advantage of the PACKAGECONFIG mechanism without having to include options from EXTRA_OECONF. To illustrate how to use PACKAGECONFIG_CONFARGS, consider the following example: PACKAGECONFIG_CONFARGS = " \ -prefix ${prefix} \ -sysroot ${STAGING_DIR_NATIVE} \ -no-gcc-sysroot " In the previous example, PACKAGECONFIG_CONFARGS is set with three configuration options that can be passed using the PACKAGECONFIG mechanism, thus avoiding having to use EXTRA_OECONF. For additional information, see the PACKAGECONFIG variable. PACKAGEGROUP_DISABLE_COMPLEMENTARY PACKAGEGROUP_DISABLE_COMPLEMENTARY[doc] = "Prevents automatic creation of the normal complementary packages such as -dev and -dbg in a packagegroup recipe." For recipes inheriting the packagegroup class, setting PACKAGEGROUP_DISABLE_COMPLEMENTARY to "1" specifies that the normal complementary packages (i.e. -dev, -dbg, and so forth) should not be automatically created by the packagegroup recipe, which is the default behavior. PACKAGES PACKAGES[doc] = "The list of packages to be created from the recipe." The list of packages to be created from the recipe. The default value is the following: ${PN}-dbg ${PN}-staticdev ${PN}-dev ${PN}-doc ${PN}-locale ${PACKAGE_BEFORE_PN} ${PN} During packaging, the do_package task goes through PACKAGES and uses the FILES variable corresponding to each package to assign files to the package. If a file matches the FILES variable for more than one package in PACKAGES, it will be assigned to the earliest (leftmost) package. Packages in the variable's list that are empty (i.e. where none of the patterns in FILES_pkg match any files installed by the do_install task) are not generated, unless generation is forced through the ALLOW_EMPTY variable. PACKAGES_DYNAMIC PACKAGES_DYNAMIC[doc] = "A promise that your recipe satisfies runtime dependencies for optional modules that are found in other recipes." A promise that your recipe satisfies runtime dependencies for optional modules that are found in other recipes. PACKAGES_DYNAMIC does not actually satisfy the dependencies, it only states that they should be satisfied. For example, if a hard, runtime dependency (RDEPENDS) of another package is satisfied at build time through the PACKAGES_DYNAMIC variable, but a package with the module name is never actually produced, then the other package will be broken. Thus, if you attempt to include that package in an image, you will get a dependency failure from the packaging system during the do_rootfs task. Typically, if there is a chance that such a situation can occur and the package that is not created is valid without the dependency being satisfied, then you should use RRECOMMENDS (a soft runtime dependency) instead of RDEPENDS. For an example of how to use the PACKAGES_DYNAMIC variable when you are splitting packages, see the "Handling Optional Module Packaging" section in the Yocto Project Development Manual. PACKAGESPLITFUNCS PACKAGESPLITFUNCS[doc] = "Specifies a list of functions run to perform additional splitting of files into individual packages." Specifies a list of functions run to perform additional splitting of files into individual packages. Recipes can either prepend to this variable or prepend to the populate_packages function in order to perform additional package splitting. In either case, the function should set PACKAGES, FILES, RDEPENDS and other packaging variables appropriately in order to perform the desired splitting. PARALLEL_MAKE PARALLEL_MAKE[doc] = "Specifies extra options that are passed to the make command during the compile tasks. This variable is usually in the form -j x, where x represents the maximum number of parallel threads make can run." Extra options passed to the make command during the do_compile task in order to specify parallel compilation on the local build host. This variable is usually in the form "-j x", where x represents the maximum number of parallel threads make can run. In order for PARALLEL_MAKE to be effective, make must be called with ${EXTRA_OEMAKE}. An easy way to ensure this is to use the oe_runmake function. By default, the OpenEmbedded build system automatically sets this variable to be equal to the number of cores the build system uses. If the software being built experiences dependency issues during the do_compile task that result in race conditions, you can clear the PARALLEL_MAKE variable within the recipe as a workaround. For information on addressing race conditions, see the "Debugging Parallel Make Races" section in the Yocto Project Development Manual. For single socket systems (i.e. one CPU), you should not have to override this variable to gain optimal parallelism during builds. However, if you have very large systems that employ multiple physical CPUs, you might want to make sure the PARALLEL_MAKE variable is not set higher than "-j 20". For more information on speeding up builds, see the "Speeding Up the Build" section. PARALLEL_MAKEINST PARALLEL_MAKEINST[doc] = "Extra options passed to the make install command during the do_install task in order to specify parallel installation." Extra options passed to the make install command during the do_install task in order to specify parallel installation. This variable defaults to the value of PARALLEL_MAKE. In order for PARALLEL_MAKEINST to be effective, make must be called with ${EXTRA_OEMAKE}. An easy way to ensure this is to use the oe_runmake function. If the software being built experiences dependency issues during the do_install task that result in race conditions, you can clear the PARALLEL_MAKEINST variable within the recipe as a workaround. For information on addressing race conditions, see the "Debugging Parallel Make Races" section in the Yocto Project Development Manual. PATCHRESOLVE PATCHRESOLVE[doc] = "Enable or disable interactive patch resolution." Determines the action to take when a patch fails. You can set this variable to one of two values: "noop" and "user". The default value of "noop" causes the build to simply fail when the OpenEmbedded build system cannot successfully apply a patch. Setting the value to "user" causes the build system to launch a shell and places you in the right location so that you can manually resolve the conflicts. Set this variable in your local.conf file. PATCHTOOL PATCHTOOL[doc] = "Specifies the utility used to apply patches for a recipe during do_patch." Specifies the utility used to apply patches for a recipe during the do_patch task. You can specify one of three utilities: "patch", "quilt", or "git". The default utility used is "quilt" except for the quilt-native recipe itself. Because the quilt tool is not available at the time quilt-native is being patched, it uses "patch". If you wish to use an alternative patching tool, set the variable in the recipe using one of the following: PATCHTOOL = "patch" PATCHTOOL = "quilt" PATCHTOOL = "git" PE PE[doc] = "The epoch of the recipe. The default value is '0'. The field is used to make upgrades possible when the versioning scheme changes in some backwards incompatible way." The epoch of the recipe. By default, this variable is unset. The variable is used to make upgrades possible when the versioning scheme changes in some backwards incompatible way. PE is the default value of the PKGE variable. PF PF[doc] = "Specifies the recipe or package name and includes all version and revision numbers. This variable is comprised of ${PN}-${EXTENDPE}${PV}-${PR}." Specifies the recipe or package name and includes all version and revision numbers (i.e. glibc-2.13-r20+svnr15508/ and bash-4.2-r1/). This variable is comprised of the following: ${PN}-${EXTENDPE}${PV}-${PR} PIXBUF_PACKAGES PIXBUF_PACKAGES[doc] = "When a recipe inherits the pixbufcache class, this variable identifies packages that contain the pixbuf loaders used with gdk-pixbuf." When inheriting the pixbufcache class, this variable identifies packages that contain the pixbuf loaders used with gdk-pixbuf. By default, the pixbufcache class assumes that the loaders are in the recipe's main package (i.e. ${PN}). Use this variable if the loaders you need are in a package other than that main package. PKG PKG[doc] = "The name of the resulting package created by the OpenEmbedded build system. When you use this variable, you must use a package name override." The name of the resulting package created by the OpenEmbedded build system. When using the PKG variable, you must use a package name override. For example, when the debian class renames the output package, it does so by setting PKG_packagename. PKG_CONFIG_PATH PKG_CONFIG_PATH[doc] = "Path to pkg-config files for the current build context." The path to pkg-config files for the current build context. pkg-config reads this variable from the environment. PKGD PKGD[doc] = "Points to the destination directory for files to be packaged before they are split into individual packages." Points to the destination directory for files to be packaged before they are split into individual packages. This directory defaults to the following: ${WORKDIR}/package Do not change this default. PKGDATA_DIR PKGDATA_DIR[doc] = "Points to a shared, global-state directory that holds data generated during the packaging process." Points to a shared, global-state directory that holds data generated during the packaging process. During the packaging process, the do_packagedata task packages data for each recipe and installs it into this temporary, shared area. This directory defaults to the following, which you should not change: ${STAGING_DIR_HOST}/pkgdata For examples of how this data is used, see the "Automatically Added Runtime Dependencies" section and the "Viewing Package Information with oe-pkgdata-util" section. PKGDEST PKGDEST[doc] = "Points to the parent directory for files to be packaged after they have been split into individual packages." Points to the parent directory for files to be packaged after they have been split into individual packages. This directory defaults to the following: ${WORKDIR}/packages-split Under this directory, the build system creates directories for each package specified in PACKAGES. Do not change this default. PKGDESTWORK PKGDESTWORK[doc] = "Points to a temporary work area where the do_package task saves package metadata." Points to a temporary work area where the do_package task saves package metadata. The PKGDESTWORK location defaults to the following: ${WORKDIR}/pkgdata Do not change this default. The do_packagedata task copies the package metadata from PKGDESTWORK to PKGDATA_DIR to make it available globally. PKGE PKGE[doc] = "The epoch of the package(s) built by the recipe." The epoch of the package(s) built by the recipe. By default, PKGE is set to PE. PKGR PKGR[doc] = "The revision of the package(s) built by the recipe." The revision of the package(s) built by the recipe. By default, PKGR is set to PR. PKGV PKGV[doc] = "The version of the package(s) built by the recipe." The version of the package(s) built by the recipe. By default, PKGV is set to PV. PN PN[doc] = "PN refers to a recipe name in the context of a file used by the OpenEmbedded build system as input to create a package. It refers to a package name in the context of a file created or produced by the OpenEmbedded build system." This variable can have two separate functions depending on the context: a recipe name or a resulting package name. PN refers to a recipe name in the context of a file used by the OpenEmbedded build system as input to create a package. The name is normally extracted from the recipe file name. For example, if the recipe is named expat_2.0.1.bb, then the default value of PN will be "expat". The variable refers to a package name in the context of a file created or produced by the OpenEmbedded build system. If applicable, the PN variable also contains any special suffix or prefix. For example, using bash to build packages for the native machine, PN is bash-native. Using bash to build packages for the target and for Multilib, PN would be bash and lib64-bash, respectively. PNBLACKLIST PNBLACKLIST[doc] = "Lists recipes you do not want the OpenEmbedded build system to build." Lists recipes you do not want the OpenEmbedded build system to build. This variable works in conjunction with the blacklist class, which the recipe must inherit globally. To prevent a recipe from being built, inherit the class globally and use the variable in your local.conf file. Here is an example that prevents myrecipe from being built: INHERIT += "blacklist" PNBLACKLIST[myrecipe] = "Not supported by our organization." POPULATE_SDK_POST_HOST_COMMAND POPULATE_SDK_POST_HOST_COMMAND[doc] = "Specifies a list of functions to call once the OpenEmbedded build system has created host part of the SDK." Specifies a list of functions to call once the OpenEmbedded build system has created the host part of the SDK. You can specify functions separated by semicolons: POPULATE_SDK_POST_HOST_COMMAND += "function; ... " If you need to pass the SDK path to a command within a function, you can use ${SDK_DIR}, which points to the parent directory used by the OpenEmbedded build system when creating SDK output. See the SDK_DIR variable for more information. POPULATE_SDK_POST_TARGET_COMMAND POPULATE_SDK_POST_TARGET_COMMAND[doc] = "Specifies a list of functions to call once the OpenEmbedded build system has created target part of the SDK." Specifies a list of functions to call once the OpenEmbedded build system has created the target part of the SDK. You can specify functions separated by semicolons: POPULATE_SDK_POST_TARGET_COMMAND += "function; ... " If you need to pass the SDK path to a command within a function, you can use ${SDK_DIR}, which points to the parent directory used by the OpenEmbedded build system when creating SDK output. See the SDK_DIR variable for more information. PR PR[doc] = "The revision of the recipe. The default value for this variable is 'r0'." The revision of the recipe. The default value for this variable is "r0". Subsequent revisions of the recipe conventionally have the values "r1", "r2", and so forth. When PV increases, PR is conventionally reset to "r0". The OpenEmbedded build system does not need the aid of PR to know when to rebuild a recipe. The build system uses the task input checksums along with the stamp and shared state cache mechanisms. The PR variable primarily becomes significant when a package manager dynamically installs packages on an already built image. In this case, PR, which is the default value of PKGR, helps the package manager distinguish which package is the most recent one in cases where many packages have the same PV (i.e. PKGV). A component having many packages with the same PV usually means that the packages all install the same upstream version, but with later (PR) version packages including packaging fixes. PR does not need to be increased for changes that do not change the package contents or metadata. Because manually managing PR can be cumbersome and error-prone, an automated solution exists. See the "Working With a PR Service" section for more information. PREFERRED_PROVIDER PREFERRED_PROVIDER[doc] = "If multiple recipes provide an item, this variable determines which recipe should be given preference." If multiple recipes provide an item, this variable determines which recipe should be given preference. You should always suffix the variable with the name of the provided item, and you should set it to the PN of the recipe to which you want to give precedence. Some examples: PREFERRED_PROVIDER_virtual/kernel ?= "linux-yocto" PREFERRED_PROVIDER_virtual/xserver = "xserver-xf86" PREFERRED_PROVIDER_virtual/libgl ?= "mesa" If you set PREFERRED_PROVIDER for a virtual/* item, then any recipe that PROVIDES that item that is not selected by PREFERRED_PROVIDER is prevented from building, which is usually desirable since this mechanism is designed to select between mutually exclusive alternative providers. PREFERRED_VERSION PREFERRED_VERSION[doc] = "If there are multiple versions of recipes available, this variable determines which recipe should be given preference." If there are multiple versions of recipes available, this variable determines which recipe should be given preference. You must always suffix the variable with the PN you want to select, and you should set the PV accordingly for precedence. You can use the "%" character as a wildcard to match any number of characters, which can be useful when specifying versions that contain long revision numbers that could potentially change. Here are two examples: PREFERRED_VERSION_python = "3.4.0" PREFERRED_VERSION_linux-yocto = "3.19%" The specified version is matched against PV, which does not necessarily match the version part of the recipe's filename. For example, consider two recipes foo_1.2.bb and foo_git.bb where foo_git.bb contains the following assignment: PV = "1.1+git${SRCPV}" In this case, the correct way to select foo_git.bb is by using an assignment such as the following: PREFERRED_VERSION_foo = "1.1+git%" Compare that previous example against the following incorrect example, which does not work: PREFERRED_VERSION_foo = "git" Sometimes the PREFERRED_VERSION variable can be set by configuration files in a way that is hard to change. You can use OVERRIDES to set a machine-specific override. Here is an example: PREFERRED_VERSION_linux-yocto_qemux86 = "3.4%" Although not recommended, worst case, you can also use the "forcevariable" override, which is the strongest override possible. Here is an example: PREFERRED_VERSION_linux-yocto_forcevariable = "3.4%" The _forcevariable override is not handled specially. This override only works because the default value of OVERRIDES includes "forcevariable". PREMIRRORS PREMIRRORS[doc] = "Specifies additional paths from which the OpenEmbedded build system gets source code." Specifies additional paths from which the OpenEmbedded build system gets source code. When the build system searches for source code, it first tries the local download directory. If that location fails, the build system tries locations defined by PREMIRRORS, the upstream source, and then locations specified by MIRRORS in that order. Assuming your distribution (DISTRO) is "poky", the default value for PREMIRRORS is defined in the conf/distro/poky.conf file in the meta-poky Git repository. Typically, you could add a specific server for the build system to attempt before any others by adding something like the following to the local.conf configuration file in the Build Directory: PREMIRRORS_prepend = "\ git://.*/.* http://www.yoctoproject.org/sources/ \n \ ftp://.*/.* http://www.yoctoproject.org/sources/ \n \ http://.*/.* http://www.yoctoproject.org/sources/ \n \ https://.*/.* http://www.yoctoproject.org/sources/ \n" These changes cause the build system to intercept Git, FTP, HTTP, and HTTPS requests and direct them to the http:// sources mirror. You can use file:// URLs to point to local directories or network shares as well. PRIORITY PRIORITY[doc] = "Indicates the importance of a package. The default value is 'optional'. Other standard values are 'required', 'standard' and 'extra'." Indicates the importance of a package. PRIORITY is considered to be part of the distribution policy because the importance of any given recipe depends on the purpose for which the distribution is being produced. Thus, PRIORITY is not normally set within recipes. You can set PRIORITY to "required", "standard", "extra", and "optional", which is the default. PRIVATE_LIBS PRIVATE_LIBS[doc] = "Specifies libraries installed within a recipe that should be ignored by the OpenEmbedded build system's shared library resolver." Specifies libraries installed within a recipe that should be ignored by the OpenEmbedded build system's shared library resolver. This variable is typically used when software being built by a recipe has its own private versions of a library normally provided by another recipe. In this case, you would not want the package containing the private libraries to be set as a dependency on other unrelated packages that should instead depend on the package providing the standard version of the library. Libraries specified in this variable should be specified by their file name. For example, from the Firefox recipe in meta-browser: PRIVATE_LIBS = "libmozjs.so \ libxpcom.so \ libnspr4.so \ libxul.so \ libmozalloc.so \ libplc4.so \ libplds4.so" For more information, see the "Automatically Added Runtime Dependencies" section. PROVIDES PROVIDES[doc] = "A list of aliases that a recipe also provides. These aliases are useful for satisfying dependencies of other recipes during the build as specified by DEPENDS." A list of aliases by which a particular recipe can be known. By default, a recipe's own PN is implicitly already in its PROVIDES list. If a recipe uses PROVIDES, the additional aliases are synonyms for the recipe and can be useful satisfying dependencies of other recipes during the build as specified by DEPENDS. Consider the following example PROVIDES statement from a recipe file libav_0.8.11.bb: PROVIDES += "libpostproc" The PROVIDES statement results in the "libav" recipe also being known as "libpostproc". In addition to providing recipes under alternate names, the PROVIDES mechanism is also used to implement virtual targets. A virtual target is a name that corresponds to some particular functionality (e.g. a Linux kernel). Recipes that provide the functionality in question list the virtual target in PROVIDES. Recipes that depend on the functionality in question can include the virtual target in DEPENDS to leave the choice of provider open. Conventionally, virtual targets have names on the form "virtual/function" (e.g. "virtual/kernel"). The slash is simply part of the name and has no syntactical significance. The PREFERRED_PROVIDER variable is used to select which particular recipe provides a virtual target. A corresponding mechanism for virtual runtime dependencies (packages) exists. However, the mechanism does not depend on any special functionality beyond ordinary variable assignments. For example, VIRTUAL-RUNTIME_dev_manager refers to the package of the component that manages the /dev directory. Setting the "preferred provider" for runtime dependencies is as simple as using the following assignment in a configuration file: VIRTUAL-RUNTIME_dev_manager = "udev" PRSERV_HOST PRSERV_HOST[doc] = "The network based PR service host and port." The network based PR service host and port. The conf/local.conf.sample.extended configuration file in the Source Directory shows how the PRSERV_HOST variable is set: PRSERV_HOST = "localhost:0" You must set the variable if you want to automatically start a local PR service. You can set PRSERV_HOST to other values to use a remote PR service. PTEST_ENABLED PRSERV_HOST[doc] = "Specifies whether or not Package Test (ptest) functionality is enabled when building a recipe." Specifies whether or not Package Test (ptest) functionality is enabled when building a recipe. You should not set this variable directly. Enabling and disabling building Package Tests at build time should be done by adding "ptest" to (or removing it from) DISTRO_FEATURES. PV PV[doc] = "The version of the recipe. The version is normally extracted from the recipe filename." The version of the recipe. The version is normally extracted from the recipe filename. For example, if the recipe is named expat_2.0.1.bb, then the default value of PV will be "2.0.1". PV is generally not overridden within a recipe unless it is building an unstable (i.e. development) version from a source code repository (e.g. Git or Subversion). PV is the default value of the PKGV variable. PYTHON_ABI PYTHON_ABI[doc] = "When used by recipes that inherit the distutils3, setuptools3, distutils, or setuptools classes, denotes the Application Binary Interface (ABI) currently in use for Python." When used by recipes that inherit the distutils3, setuptools3, distutils, or setuptools classes, denotes the Application Binary Interface (ABI) currently in use for Python. By default, the ABI is "m". You do not have to set this variable as the OpenEmbedded build system sets it for you. The OpenEmbedded build system uses the ABI to construct directory names used when installing the Python headers and libraries in sysroot (e.g. .../python3.3m/...). Recipes that inherit the distutils class during cross-builds also use this variable to locate the headers and libraries of the appropriate Python that the extension is targeting. PYTHON_PN PYTHON_PN[doc] = "When used by recipes that inherit the distutils3, setuptools3, distutils, or setuptools classes, specifies the major Python version being built." When used by recipes that inherit the distutils3, setuptools3, distutils, or setuptools classes, specifies the major Python version being built. For Python 2.x, PYTHON_PN would be "python2". For Python 3.x, the variable would be "python3". You do not have to set this variable as the OpenEmbedded build system automatically sets it for you. The variable allows recipes to use common infrastructure such as the following: DEPENDS += "${PYTHON_PN}-native" In the previous example, the version of the dependency is PYTHON_PN. RANLIB RANLIB[doc] = "Minimal command and arguments to run 'ranlib'." The minimal command and arguments to run ranlib. RCONFLICTS RCONFLICTS[doc] = "The list of packages that conflict with another package. Note that the package will not be installed if the conflicting packages are not first removed." The list of packages that conflict with packages. Note that packages will not be installed if conflicting packages are not first removed. Like all package-controlling variables, you must always use them in conjunction with a package name override. Here is an example: RCONFLICTS_${PN} = "another_conflicting_package_name" BitBake, which the OpenEmbedded build system uses, supports specifying versioned dependencies. Although the syntax varies depending on the packaging format, BitBake hides these differences from you. Here is the general syntax to specify versions with the RCONFLICTS variable: RCONFLICTS_${PN} = "package (operator version)" For operator, you can specify the following: = < > <= >= For example, the following sets up a dependency on version 1.2 or greater of the package foo: RCONFLICTS_${PN} = "foo (>= 1.2)" RDEPENDS RDEPENDS[doc] = "Lists runtime dependencies of a package." Lists runtime dependencies of a package. These dependencies are other packages that must be installed in order for the package to function correctly. As an example, the following assignment declares that the package foo needs the packages bar and baz to be installed: RDEPENDS_foo = "bar baz" The most common types of package runtime dependencies are automatically detected and added. Therefore, most recipes do not need to set RDEPENDS. For more information, see the "Automatically Added Runtime Dependencies" section. The practical effect of the above RDEPENDS assignment is that bar and baz will be declared as dependencies inside the package foo when it is written out by one of the do_package_write_* tasks. Exactly how this is done depends on which package format is used, which is determined by PACKAGE_CLASSES. When the corresponding package manager installs the package, it will know to also install the packages on which it depends. To ensure that the packages bar and baz get built, the previous RDEPENDS assignment also causes a task dependency to be added. This dependency is from the recipe's do_build (not to be confused with do_compile) task to the do_package_write_* task of the recipes that build bar and baz. The names of the packages you list within RDEPENDS must be the names of other packages - they cannot be recipe names. Although package names and recipe names usually match, the important point here is that you are providing package names within the RDEPENDS variable. For an example of the default list of packages created from a recipe, see the PACKAGES variable. Because the RDEPENDS variable applies to packages being built, you should always use the variable in a form with an attached package name (remember that a single recipe can build multiple packages). For example, suppose you are building a development package that depends on the perl package. In this case, you would use the following RDEPENDS statement: RDEPENDS_${PN}-dev += "perl" In the example, the development package depends on the perl package. Thus, the RDEPENDS variable has the ${PN}-dev package name as part of the variable. RDEPENDS_${PN}-dev includes ${PN} by default. This default is set in the BitBake configuration file (meta/conf/bitbake.conf). Be careful not to accidentally remove ${PN} when modifying RDEPENDS_${PN}-dev. Use the "+=" operator rather than the "=" operator. The package names you use with RDEPENDS must appear as they would in the PACKAGES variable. The PKG variable allows a different name to be used for the final package (e.g. the debian class uses this to rename packages), but this final package name cannot be used with RDEPENDS, which makes sense as RDEPENDS is meant to be independent of the package format used. BitBake, which the OpenEmbedded build system uses, supports specifying versioned dependencies. Although the syntax varies depending on the packaging format, BitBake hides these differences from you. Here is the general syntax to specify versions with the RDEPENDS variable: RDEPENDS_${PN} = "package (operator version)" For operator, you can specify the following: = < > <= >= For version, provide the version number. You can use EXTENDPKGV to provide a full package version specification. For example, the following sets up a dependency on version 1.2 or greater of the package foo: RDEPENDS_${PN} = "foo (>= 1.2)" For information on build-time dependencies, see the DEPENDS variable. You can also see the "Tasks" and "Dependencies" sections in the BitBake User Manual for additional information on tasks and dependencies. REQUIRED_DISTRO_FEATURES REQUIRED_DISTRO_FEATURES[doc] = "When a recipe inherits the distro_features_check class, this variable identifies distribution features that must exist in the current configuration in order for the OpenEmbedded build system to build the recipe." When inheriting the distro_features_check class, this variable identifies distribution features that must exist in the current configuration in order for the OpenEmbedded build system to build the recipe. In other words, if the REQUIRED_DISTRO_FEATURES variable lists a feature that does not appear in DISTRO_FEATURES within the current configuration, an error occurs and the build stops. RM_WORK_EXCLUDE RM_WORK_EXCLUDE[doc] = "With rm_work enabled, this variable specifies a list of packages whose work directories should not be removed." With rm_work enabled, this variable specifies a list of recipes whose work directories should not be removed. See the "rm_work.bbclass" section for more details. ROOT_HOME ROOT_HOME[doc] = "Defines the root home directory." Defines the root home directory. By default, this directory is set as follows in the BitBake configuration file: ROOT_HOME ??= "/home/root" This default value is likely used because some embedded solutions prefer to have a read-only root filesystem and prefer to keep writeable data in one place. You can override the default by setting the variable in any layer or in the local.conf file. Because the default is set using a "weak" assignment (i.e. "??="), you can use either of the following forms to define your override: ROOT_HOME = "/root" ROOT_HOME ?= "/root" These override examples use /root, which is probably the most commonly used override. ROOTFS ROOTFS[doc] = "Indicates a filesystem image to include as the root filesystem." Indicates a filesystem image to include as the root filesystem. The ROOTFS variable is an optional variable used with the image-live class. ROOTFS_POSTINSTALL_COMMAND ROOTFS_POSTINSTALL_COMMAND[doc] = "Specifies a list of functions to call after installing packages." Specifies a list of functions to call after the OpenEmbedded build system has installed packages. You can specify functions separated by semicolons: ROOTFS_POSTINSTALL_COMMAND += "function; ... " If you need to pass the root filesystem path to a command within a function, you can use ${IMAGE_ROOTFS}, which points to the directory that becomes the root filesystem image. See the IMAGE_ROOTFS variable for more information. ROOTFS_POSTPROCESS_COMMAND ROOTFS_POSTPROCESS_COMMAND[doc] = "Specifies a list of functions to call once the OpenEmbedded build system has created the root filesystem." Specifies a list of functions to call once the OpenEmbedded build system has created the root filesystem. You can specify functions separated by semicolons: ROOTFS_POSTPROCESS_COMMAND += "function; ... " If you need to pass the root filesystem path to a command within a function, you can use ${IMAGE_ROOTFS}, which points to the directory that becomes the root filesystem image. See the IMAGE_ROOTFS variable for more information. ROOTFS_POSTUNINSTALL_COMMAND ROOTFS_POSTUNINSTALL_COMMAND[doc] = "Specifies a list of functions to call after removal of unneeded packages." Specifies a list of functions to call after the OpenEmbedded build system has removed unnecessary packages. When runtime package management is disabled in the image, several packages are removed including base-passwd, shadow, and update-alternatives. You can specify functions separated by semicolons: ROOTFS_POSTUNINSTALL_COMMAND += "function; ... " If you need to pass the root filesystem path to a command within a function, you can use ${IMAGE_ROOTFS}, which points to the directory that becomes the root filesystem image. See the IMAGE_ROOTFS variable for more information. ROOTFS_PREPROCESS_COMMAND ROOTFS_PREPROCESS_COMMAND[doc] = "Specifies a list of functions to call before the OpenEmbedded build system has created the root filesystem." Specifies a list of functions to call before the OpenEmbedded build system has created the root filesystem. You can specify functions separated by semicolons: ROOTFS_PREPROCESS_COMMAND += "function; ... " If you need to pass the root filesystem path to a command within a function, you can use ${IMAGE_ROOTFS}, which points to the directory that becomes the root filesystem image. See the IMAGE_ROOTFS variable for more information. RPROVIDES RPROVIDES[doc] = "A list of package name aliases that a package also provides. These aliases are useful for satisfying runtime dependencies of other packages both during the build and on the target." A list of package name aliases that a package also provides. These aliases are useful for satisfying runtime dependencies of other packages both during the build and on the target (as specified by RDEPENDS). A package's own name is implicitly already in its RPROVIDES list. As with all package-controlling variables, you must always use the variable in conjunction with a package name override. Here is an example: RPROVIDES_${PN} = "widget-abi-2" RRECOMMENDS RRECOMMENDS[doc] = "A list of packages that extends the usability of a package being built. The package being built does not depend on this list of packages in order to successfully build, but needs them for the extended usability." A list of packages that extends the usability of a package being built. The package being built does not depend on this list of packages in order to successfully build, but rather uses them for extended usability. To specify runtime dependencies for packages, see the RDEPENDS variable. The package manager will automatically install the RRECOMMENDS list of packages when installing the built package. However, you can prevent listed packages from being installed by using the BAD_RECOMMENDATIONS, NO_RECOMMENDATIONS, and PACKAGE_EXCLUDE variables. Packages specified in RRECOMMENDS need not actually be produced. However, a recipe must exist that provides each package, either through the PACKAGES or PACKAGES_DYNAMIC variables or the RPROVIDES variable, or an error will occur during the build. If such a recipe does exist and the package is not produced, the build continues without error. Because the RRECOMMENDS variable applies to packages being built, you should always attach an override to the variable to specify the particular package whose usability is being extended. For example, suppose you are building a development package that is extended to support wireless functionality. In this case, you would use the following: RRECOMMENDS_${PN}-dev += "wireless_package_name" In the example, the package name (${PN}-dev) must appear as it would in the PACKAGES namespace before any renaming of the output package by classes such as debian.bbclass. BitBake, which the OpenEmbedded build system uses, supports specifying versioned recommends. Although the syntax varies depending on the packaging format, BitBake hides these differences from you. Here is the general syntax to specify versions with the RRECOMMENDS variable: RRECOMMENDS_${PN} = "package (operator version)" For operator, you can specify the following: = < > <= >= For example, the following sets up a recommend on version 1.2 or greater of the package foo: RRECOMMENDS_${PN} = "foo (>= 1.2)" RREPLACES RREPLACES[doc] = "A list of packages replaced by a package. The package manager uses this variable to determine which package should be installed to replace other package(s) during an upgrade." A list of packages replaced by a package. The package manager uses this variable to determine which package should be installed to replace other package(s) during an upgrade. In order to also have the other package(s) removed at the same time, you must add the name of the other package to the RCONFLICTS variable. As with all package-controlling variables, you must use this variable in conjunction with a package name override. Here is an example: RREPLACES_${PN} = "other_package_being_replaced" BitBake, which the OpenEmbedded build system uses, supports specifying versioned replacements. Although the syntax varies depending on the packaging format, BitBake hides these differences from you. Here is the general syntax to specify versions with the RREPLACES variable: RREPLACES_${PN} = "package (operator version)" For operator, you can specify the following: = < > <= >= For example, the following sets up a replacement using version 1.2 or greater of the package foo: RREPLACES_${PN} = "foo (>= 1.2)" RSUGGESTS RSUGGESTS[doc] = "A list of additional packages that you can suggest for installation by the package manager at the time a package is installed. Not all package managers support this functionality." A list of additional packages that you can suggest for installation by the package manager at the time a package is installed. Not all package managers support this functionality. As with all package-controlling variables, you must always use this variable in conjunction with a package name override. Here is an example: RSUGGESTS_${PN} = "useful_package another_package" S S[doc] = "The location in the Build Directory where unpacked package source code resides." The location in the Build Directory where unpacked recipe source code resides. By default, this directory is ${WORKDIR}/${BPN}-${PV}, where ${BPN} is the base recipe name and ${PV} is the recipe version. If the source tarball extracts the code to a directory named anything other than ${BPN}-${PV}, or if the source code if fetched from an SCM such as Git or Subversion, then you must set S in the recipe so that the OpenEmbedded build system knows where to find the unpacked source. As an example, assume a Source Directory top-level folder named poky and a default Build Directory at poky/build. In this case, the work directory the build system uses to keep the unpacked recipe for db is the following: poky/build/tmp/work/qemux86-poky-linux/db/5.1.19-r3/db-5.1.19 The unpacked source code resides in the db-5.1.19 folder. This next example assumes a Git repository. By default, Git repositories are cloned to ${WORKDIR}/git during do_fetch. Since this path is different from the default value of S, you must set it specifically so the source can be located: SRC_URI = "git://path/to/repo.git" S = "${WORKDIR}/git" SANITY_REQUIRED_UTILITIES SANITY_REQUIRED_UTILITIES[doc] = "Specifies a list of command-line utilities that should be checked for during the initial sanity checking process when running BitBake." Specifies a list of command-line utilities that should be checked for during the initial sanity checking process when running BitBake. If any of the utilities are not installed on the build host, then BitBake immediately exits with an error. SANITY_TESTED_DISTROS SANITY_TESTED_DISTROS[doc] = "A list of the host distribution identifiers that the build system has been tested against." A list of the host distribution identifiers that the build system has been tested against. Identifiers consist of the host distributor ID followed by the release, as reported by the lsb_release tool or as read from /etc/lsb-release. Separate the list items with explicit newline characters (\n). If SANITY_TESTED_DISTROS is not empty and the current value of NATIVELSBSTRING does not appear in the list, then the build system reports a warning that indicates the current host distribution has not been tested as a build host. SDK_ARCH SDK_ARCH[doc] = "The target architecture for the SDK." The target architecture for the SDK. Typically, you do not directly set this variable. Instead, use SDKMACHINE. SDK_DEPLOY SDK_DEPLOY[doc] = "The directory set up and used by the populate_sdk_base to which the SDK is deployed." The directory set up and used by the populate_sdk_base to which the SDK is deployed. The populate_sdk_base class defines SDK_DEPLOY as follows: SDK_DEPLOY = "${TMPDIR}/deploy/sdk" SDK_DIR SDK_DIR[doc] = "The parent directory used by the OpenEmbedded build system when creating SDK output." The parent directory used by the OpenEmbedded build system when creating SDK output. The populate_sdk_base class defines the variable as follows: SDK_DIR = "${WORKDIR}/sdk" The SDK_DIR directory is a temporary directory as it is part of WORKDIR. The final output directory is SDK_DEPLOY. SDK_EXT_TYPE SDK_EXT_TYPE[doc] = "Controls whether or not shared state artifacts are copied into the extensible SDK." Controls whether or not shared state artifacts are copied into the extensible SDK. The default value of "full" copies all of the required shared state artifacts into the extensible SDK. The value "minimal" leaves these artifacts out of the SDK. If you set the variable to "minimal", you need to ensure SSTATE_MIRRORS is set in the SDK's configuration to enable the artifacts to be fetched as needed. SDK_HOST_MANIFEST SDK_HOST_MANIFEST[doc] = "The manifest file for the host part of the SDK. This file lists all the installed packages that make up the host part of the SDK." The manifest file for the host part of the SDK. This file lists all the installed packages that make up the host part of SDK. The file contains package information on a line-per-package basis as follows: packagename packagearch version The populate_sdk_base class defines the manifest file as follows: SDK_HOST_MANIFEST = "${SDK_DEPLOY}/${TOOLCHAIN_OUTPUTNAME}.host.manifest" The location is derived using the SDK_DEPLOY and TOOLCHAIN_OUTPUTNAME variables. SDK_INCLUDE_PKGDATA SDK_INCLUDE_PKGDATA[doc] = "When set to "1", specifies to include the packagedata for all recipes in the "world" target in the extensible SDK." When set to "1", specifies to include the packagedata for all recipes in the "world" target in the extensible SDK. Including this data allows the devtool search command to find these recipes in search results, as well as allows the devtool add command to map dependencies more effectively. Enabling the SDK_INCLUDE_PKGDATA variable significantly increases build time because all of world needs to be built. Enabling the variable also slightly increases the size of the extensible SDK. SDK_INCLUDE_TOOLCHAIN SDK_INCLUDE_TOOLCHAIN[doc] = "When set to "1", specifies to include the toolchain in the extensible SDK." When set to "1", specifies to include the toolchain in the extensible SDK. Including the toolchain is useful particularly when SDK_EXT_TYPE is set to "minimal" to keep the SDK reasonably small but you still want to provide a usable toolchain. For example, suppose you want to use the toolchain from an IDE (e.g. Eclipse) or from other tools and you do not want to perform additional steps to install the toolchain. The SDK_INCLUDE_TOOLCHAIN variable defaults to "0" if SDK_EXT_TYPE is set to "minimal", and defaults to "1" if SDK_EXT_TYPE is set to "full". SDK_INHERIT_BLACKLIST SDK_INHERIT_BLACKLIST[doc] = "A list of classes to remove from the INHERIT value globally within the extensible SDK configuration." A list of classes to remove from the INHERIT value globally within the extensible SDK configuration. The default value is "buildhistory icecc". Some classes are not generally applicable within the extensible SDK context and you can use this variable to disable them. SDK_LOCAL_CONF_BLACKLIST SDK_LOCAL_CONF_BLACKLIST[doc] = "A list of variables not allowed through from the build system configuration into the extensible SDK configuration." A list of variables not allowed through from the build system configuration into the extensible SDK configuration. Usually, these are variables that are specific to the machine on which the build system is running and thus would be potentially problematic within the extensible SDK. SDK_LOCAL_CONF_WHITELIST SDK_LOCAL_CONF_WHITELIST[doc] = "A list of variables allowed through from the build system configuration into the extensible SDK configuration." A list of variables allowed through from the build system configuration into the extensible SDK configuration. This list overrides the variables specified using the SDK_LOCAL_CONF_BLACKLIST variable as well as any variables identified by automatic blacklisting due to the "/" character being found at the start of the value, which is usually indicative of being a path and thus might not be valid on the system where the SDK is installed. SDK_NAME SDK_NAME[doc] = "The base name for SDK output files." The base name for SDK output files. The name is derived from the DISTRO, TCLIBC, SDK_ARCH, IMAGE_BASENAME, and TUNE_PKGARCH variables: SDK_NAME = "${DISTRO}-${TCLIBC}-${SDK_ARCH}-${IMAGE_BASENAME}-${TUNE_PKGARCH}" SDK_OS SDK_OS[doc] = "The operating system for which the SDK will be built." Specifies the operating system for which the SDK will be built. The default value is the value of BUILD_OS. SDK_OUTPUT SDK_OUTPUT[doc] = "The location used by the OpenEmbedded build system when creating SDK output." The location used by the OpenEmbedded build system when creating SDK output. The populate_sdk_base class defines the variable as follows: SDK_OUTPUT = "${SDK_DIR}/image" The SDK_OUTPUT directory is a temporary directory as it is part of WORKDIR by way of SDK_DIR. The final output directory is SDK_DEPLOY. SDK_PACKAGE_ARCHS SDK_PACKAGE_ARCHS[doc] = "Specifies a list of architectures compatible with the SDK machine. This variable is set automatically and should not normally be hand-edited." Specifies a list of architectures compatible with the SDK machine. This variable is set automatically and should not normally be hand-edited. Entries are separated using spaces and listed in order of priority. The default value for SDK_PACKAGE_ARCHS is "all any noarch ${SDK_ARCH}-${SDKPKGSUFFIX}". SDK_POSTPROCESS_COMMAND SDK_POSTPROCESS_COMMAND[doc] = "Specifies a list of functions to call once the OpenEmbedded build system has created the SDK." Specifies a list of functions to call once the OpenEmbedded build system has created the SDK. You can specify functions separated by semicolons: SDK_POSTPROCESS_COMMAND += "function; ... " If you need to pass an SDK path to a command within a function, you can use ${SDK_DIR}, which points to the parent directory used by the OpenEmbedded build system when creating SDK output. See the SDK_DIR variable for more information. SDK_PREFIX SDK_PREFIX[doc] = "The toolchain binary prefix used for nativesdk recipes." The toolchain binary prefix used for nativesdk recipes. The OpenEmbedded build system uses the SDK_PREFIX value to set the TARGET_PREFIX when building nativesdk recipes. The default value is "${SDK_SYS}-". SDK_RECRDEP_TASKS SDK_RECRDEP_TASKS[doc] = "A list of shared state tasks added to the extensible SDK." A list of shared state tasks added to the extensible SDK. By default, the following tasks are added: do_populate_lic do_package_qa do_populate_sysroot do_deploy Despite the default value of "" for the SDK_RECRDEP_TASKS variable, the above four tasks are always added to the SDK. To specify tasks beyond these four, you need to use the SDK_RECRDEP_TASKS variable (e.g. you are defining additional tasks that are needed in order to build SDK_TARGETS). SDK_SYS SDK_SYS[doc] = "Specifies the system, including the architecture and the operating system, for which the SDK will be built." Specifies the system, including the architecture and the operating system, for which the SDK will be built. The OpenEmbedded build system automatically sets this variable based on SDK_ARCH, SDK_VENDOR, and SDK_OS. You do not need to set the SDK_SYS variable yourself. SDK_TARGET_MANIFEST SDK_TARGET_MANIFEST[doc] = "The manifest file for the target part of the SDK. This file lists all the installed packages that make up the target part of the SDK." The manifest file for the target part of the SDK. This file lists all the installed packages that make up the target part of the SDK. The file contains package information on a line-per-package basis as follows: packagename packagearch version The populate_sdk_base class defines the manifest file as follows: SDK_TARGET_MANIFEST = "${SDK_DEPLOY}/${TOOLCHAIN_OUTPUTNAME}.target.manifest" The location is derived using the SDK_DEPLOY and TOOLCHAIN_OUTPUTNAME variables. SDK_TARGETS SDK_TARGETS[doc] = "A list of targets to install from shared state as part of the standard or extensible SDK installation." A list of targets to install from shared state as part of the standard or extensible SDK installation. The default value is "${PN}" (i.e. the image from which the SDK is built). The SDK_TARGETS variable is an internal variable and typically would not be changed. SDK_TITLE SDK_TITLE[doc] = "Specifies a title to be printed when running the SDK installer." Specifies a title to be printed when running the SDK installer. The SDK_TITLE variable defaults to "distro SDK" for the standard SDK and "distro Extensible SDK" for the extensible SDK, where distro is the first one of DISTRO_NAME or DISTRO that is set in your configuration. SDK_UPDATE_URL SDK_UPDATE_URL[doc] = "An optional URL for an update server for the extensible SDK." An optional URL for an update server for the extensible SDK. If set, the value is used as the default update server when running devtool sdk-update within the extensible SDK. SDK_VENDOR SDK_VENDOR[doc] = "Specifies the name of the SDK vendor." Specifies the name of the SDK vendor. SDK_VERSION SDK_VERSION[doc] = "Specifies the version for the SDK." Specifies the version of the SDK. The distribution configuration file (e.g. /meta-poky/conf/distro/poky.conf) defines the SDK_VERSION as follows: SDK_VERSION := "${@'${DISTRO_VERSION}'.replace('snapshot-${DATE}','snapshot')}" For additional information, see the DISTRO_VERSION and DATE variables. SDKIMAGE_FEATURES SDKIMAGE_FEATURES[doc] = "Equivalent to IMAGE_FEATURES. However, this variable applies to the SDK generated from an image using the command 'bitbake -c populate_sdk imagename'." Equivalent to IMAGE_FEATURES. However, this variable applies to the SDK generated from an image using the following command: $ bitbake -c populate_sdk imagename SDKMACHINE SDKMACHINE[doc] = "Specifies the architecture (i.e. i686 or x86_64) for which to build SDK items." The machine for which the SDK is built. In other words, the SDK is built such that it runs on the target you specify with the SDKMACHINE value. The value points to a corresponding .conf file under conf/machine-sdk/. You can use "i686" and "x86_64" as possible values for this variable. The variable defaults to "i686" and is set in the local.conf file in the Build Directory. SDKMACHINE ?= "i686" You cannot set the SDKMACHINE variable in your distribution configuration file. If you do, the configuration will not take affect. SDKPATH SDKPATH[doc] = "Defines the path offered to the user for installation of the SDK that is generated by the OpenEmbedded build system." Defines the path offered to the user for installation of the SDK that is generated by the OpenEmbedded build system. The path appears as the default location for installing the SDK when you run the SDK's installation script. You can override the offered path when you run the script. SDKTARGETSYSROOT SDKTARGETSYSROOT[doc] = "Full path to the sysroot used for cross-compilation within an SDK as it will be when installed into the default SDKPATH." The full path to the sysroot used for cross-compilation within an SDK as it will be when installed into the default SDKPATH. SECTION SECTION[doc] = "The section in which packages should be categorized. Package management utilities can make use of this variable." The section in which packages should be categorized. Package management utilities can make use of this variable. SELECTED_OPTIMIZATION SELECTED_OPTIMIZATION[doc] = "The variable takes the value of FULL_OPTIMIZATION unless DEBUG_BUILD = '1'. In this case, the value of DEBUG_OPTIMIZATION is used." Specifies the optimization flags passed to the C compiler when building for the target. The flags are passed through the default value of the TARGET_CFLAGS variable. The SELECTED_OPTIMIZATION variable takes the value of FULL_OPTIMIZATION unless DEBUG_BUILD = "1". If that is the case, the value of DEBUG_OPTIMIZATION is used. SERIAL_CONSOLE SERIAL_CONSOLE[doc] = "The speed and device for the serial port used to attach the serial console. This variable is given to the kernel as the 'console' parameter. After booting occurs, getty is started on that port so remote login is possible." Defines a serial console (TTY) to enable using getty. Provide a value that specifies the baud rate followed by the TTY device name separated by a space. You cannot specify more than one TTY device: SERIAL_CONSOLE = "115200 ttyS0" The SERIAL_CONSOLE variable is deprecated. Please use the SERIAL_CONSOLES variable. SERIAL_CONSOLES SERIAL_CONSOLES[doc] = "Defines the serial consoles (TTYs) to enable using getty." Defines the serial consoles (TTYs) to enable using getty. Provide a value that specifies the baud rate followed by the TTY device name separated by a semicolon. Use spaces to separate multiple devices: SERIAL_CONSOLES = "115200;ttyS0 115200;ttyS1" SERIAL_CONSOLES_CHECK SERIAL_CONSOLES_CHECK[doc] = "Selected SERIAL_CONSOLES to check against /proc/console before enabling using getty. Supported only by SysVinit." Specifies serial consoles, which must be listed in SERIAL_CONSOLES, to check against /proc/console before enabling them using getty. This variable allows aliasing in the format: <device>:<alias>. If a device was listed as "sclp_line0" in /dev/ and "ttyS0" was listed in /proc/console, you would do the following: SERIAL_CONSOLES_CHECK = "slcp_line0:ttyS0" This variable is currently only supported with SysVinit (i.e. not with systemd). SIGGEN_EXCLUDE_SAFE_RECIPE_DEPS SIGGEN_EXCLUDE_SAFE_RECIPE_DEPS[doc] = "A list of recipe dependencies that should not be used to determine signatures of tasks from one recipe when they depend on tasks from another recipe." A list of recipe dependencies that should not be used to determine signatures of tasks from one recipe when they depend on tasks from another recipe. For example: SIGGEN_EXCLUDE_SAFE_RECIPE_DEPS += "intone->mplayer2" In this example, intone depends on mplayer2. Use of this variable is one mechanism to remove dependencies that affect task signatures and thus force rebuilds when a recipe changes. If you add an inappropriate dependency for a recipe relationship, the software might break during runtime if the interface of the second recipe was changed after the first recipe had been built. SIGGEN_EXCLUDERECIPES_ABISAFE SIGGEN_EXCLUDERECIPES_ABISAFE[doc] = "A list of recipes that are completely stable and will never change." A list of recipes that are completely stable and will never change. The ABI for the recipes in the list are presented by output from the tasks run to build the recipe. Use of this variable is one way to remove dependencies from one recipe on another that affect task signatures and thus force rebuilds when the recipe changes. If you add an inappropriate variable to this list, the software might break at runtime if the interface of the recipe was changed after the other had been built. SITEINFO_BITS SITEINFO_BITS[doc] = "Specifies the number of bits for the target system CPU." Specifies the number of bits for the target system CPU. The value should be either "32" or "64". SITEINFO_ENDIANNESS SITEINFO_ENDIANNESS[doc] = "Specifies the endian byte order of the target system. The value should be either 'le' for 'little-endian' or 'be' for 'big-endian'." Specifies the endian byte order of the target system. The value should be either "le" for little-endian or "be" for big-endian. SKIP_FILEDEPS SKIP_FILEDEPS[doc] = "Enables you to remove all files from the "Provides" section of an RPM package." Enables removal of all files from the "Provides" section of an RPM package. Removal of these files is required for packages containing prebuilt binaries and libraries such as libstdc++ and glibc. To enable file removal, set the variable to "1" in your conf/local.conf configuration file in your: Build Directory. SKIP_FILEDEPS = "1" SOC_FAMILY SOC_FAMILY[doc] = "Groups together machines based upon the same family of SOC (System On Chip). You typically set this variable in a common .inc file that you include in the configuration files of all the machines." Groups together machines based upon the same family of SOC (System On Chip). You typically set this variable in a common .inc file that you include in the configuration files of all the machines. You must include conf/machine/include/soc-family.inc for this variable to appear in MACHINEOVERRIDES. SOLIBS SOLIBS[doc] = "Defines the suffix for shared libraries used on the target platform." Defines the suffix for shared libraries used on the target platform. By default, this suffix is ".so.*" for all Linux-based systems and is defined in the meta/conf/bitbake.conf configuration file. You will see this variable referenced in the default values of FILES_${PN}. SOLIBSDEV SOLIBSDEV[doc] = "Defines the suffix for the development symbolic link (symlink) for shared libraries on the target platform." Defines the suffix for the development symbolic link (symlink) for shared libraries on the target platform. By default, this suffix is ".so" for Linux-based systems and is defined in the meta/conf/bitbake.conf configuration file. You will see this variable referenced in the default values of FILES_${PN}-dev. SOURCE_MIRROR_FETCH SOURCE_MIRROR_FETCH[doc] = "Set as part of a source mirror generation script to skip COMPATIBLE_MACHINE and COMPATIBLE_HOST checks." When you are fetching files to create a mirror of sources (i.e. creating a source mirror), setting SOURCE_MIRROR_FETCH to "1" in your local.conf configuration file ensures the source for all recipes are fetched regardless of whether or not a recipe is compatible with the configuration. A recipe is considered incompatible with the currently configured machine when either or both the COMPATIBLE_MACHINE variable and COMPATIBLE_HOST variables specify compatibility with a machine other than that of the current machine or host. Do not set the SOURCE_MIRROR_FETCH variable unless you are creating a source mirror. In other words, do not set the variable during a normal build. SOURCE_MIRROR_URL SOURCE_MIRROR_URL[doc] = "URL to source mirror that will be used before fetching from original SRC_URI." Defines your own PREMIRRORS from which to first fetch source before attempting to fetch from the upstream specified in SRC_URI. To use this variable, you must globally inherit the own-mirrors class and then provide the URL to your mirrors. Here is the general syntax: INHERIT += "own-mirrors" SOURCE_MIRROR_URL = "http://example.com/my_source_mirror" You can specify only a single URL in SOURCE_MIRROR_URL. SPDXLICENSEMAP SPDXLICENSEMAP[doc] = "Maps commonly used license names to their SPDX counterparts found in meta/files/common-licenses/." Maps commonly used license names to their SPDX counterparts found in meta/files/common-licenses/. For the default SPDXLICENSEMAP mappings, see the meta/conf/licenses.conf file. For additional information, see the LICENSE variable. SPECIAL_PKGSUFFIX SPECIAL_PKGSUFFIX[doc] = "A list of prefixes for PN used by the OpenEmbedded build system to create variants of recipes or packages. The list specifies the prefixes to strip off during certain circumstances such as the generation of the BPN variable." A list of prefixes for PN used by the OpenEmbedded build system to create variants of recipes or packages. The list specifies the prefixes to strip off during certain circumstances such as the generation of the BPN variable. SRC_URI SRC_URI[doc] = "The list of source files - local or remote. This variable tells the OpenEmbedded build system what bits to pull in for the build and how to pull them in." The list of source files - local or remote. This variable tells the OpenEmbedded build system which bits to pull in for the build and how to pull them in. For example, if the recipe or append file only needs to fetch a tarball from the Internet, the recipe or append file uses a single SRC_URI entry. On the other hand, if the recipe or append file needs to fetch a tarball, apply two patches, and include a custom file, the recipe or append file would include four instances of the variable. The following list explains the available URI protocols. URI protocols are highly dependent on particular BitBake Fetcher submodules. Depending on the fetcher BitBake uses, various URL parameters are employed. For specifics on the supported Fetchers, see the "Fetchers" section in the BitBake User Manual. file:// - Fetches files, which are usually files shipped with the Metadata, from the local machine. The path is relative to the FILESPATH variable. Thus, the build system searches, in order, from the following directories, which are assumed to be a subdirectories of the directory in which the recipe file (.bb) or append file (.bbappend) resides: ${BPN} - The base recipe name without any special suffix or version numbers. ${BP} - ${BPN}-${PV}. The base recipe name and version but without any special package name suffix. files - Files within a directory, which is named files and is also alongside the recipe or append file. If you want the build system to pick up files specified through a SRC_URI statement from your append file, you need to be sure to extend the FILESPATH variable by also using the FILESEXTRAPATHS variable from within your append file. bzr:// - Fetches files from a Bazaar revision control repository. git:// - Fetches files from a Git revision control repository. osc:// - Fetches files from an OSC (OpenSUSE Build service) revision control repository. repo:// - Fetches files from a repo (Git) repository. ccrc:// - Fetches files from a ClearCase repository. http:// - Fetches files from the Internet using http. https:// - Fetches files from the Internet using https. ftp:// - Fetches files from the Internet using ftp. cvs:// - Fetches files from a CVS revision control repository. hg:// - Fetches files from a Mercurial (hg) revision control repository. p4:// - Fetches files from a Perforce (p4) revision control repository. ssh:// - Fetches files from a secure shell. svn:// - Fetches files from a Subversion (svn) revision control repository. Standard and recipe-specific options for SRC_URI exist. Here are standard options: apply - Whether to apply the patch or not. The default action is to apply the patch. striplevel - Which striplevel to use when applying the patch. The default level is 1. patchdir - Specifies the directory in which the patch should be applied. The default is ${S}. Here are options specific to recipes building code from a revision control system: mindate - Apply the patch only if SRCDATE is equal to or greater than mindate. maxdate - Apply the patch only if SRCDATE is not later than mindate. minrev - Apply the patch only if SRCREV is equal to or greater than minrev. maxrev - Apply the patch only if SRCREV is not later than maxrev. rev - Apply the patch only if SRCREV is equal to rev. notrev - Apply the patch only if SRCREV is not equal to rev. Here are some additional options worth mentioning: unpack - Controls whether or not to unpack the file if it is an archive. The default action is to unpack the file. destsuffix - Places the file (or extracts its contents) into the specified subdirectory of WORKDIR when the Git fetcher is used. subdir - Places the file (or extracts its contents) into the specified subdirectory of WORKDIR when the local (file://) fetcher is used. localdir - Places the file (or extracts its contents) into the specified subdirectory of WORKDIR when the CVS fetcher is used. subpath - Limits the checkout to a specific subpath of the tree when using the Git fetcher is used. name - Specifies a name to be used for association with SRC_URI checksums when you have more than one file specified in SRC_URI. downloadfilename - Specifies the filename used when storing the downloaded file. SRC_URI_OVERRIDES_PACKAGE_ARCH SRC_URI_OVERRIDES_PACKAGE_ARCH[doc] = "By default, the OpenEmbedded build system automatically detects whether SRC_URI contains files that are machine-specific. If so, the build system automatically changes PACKAGE_ARCH. Setting this variable to '0' disables this behavior." By default, the OpenEmbedded build system automatically detects whether SRC_URI contains files that are machine-specific. If so, the build system automatically changes PACKAGE_ARCH. Setting this variable to "0" disables this behavior. SRCDATE SRCDATE[doc] = "The date of the source code used to build the package. This variable applies only if the source was fetched from a Source Code Manager (SCM)." The date of the source code used to build the package. This variable applies only if the source was fetched from a Source Code Manager (SCM). SRCPV SRCPV[doc] = "Returns the version string of the current package. This string is used to help define the value of PV." Returns the version string of the current package. This string is used to help define the value of PV. The SRCPV variable is defined in the meta/conf/bitbake.conf configuration file in the Source Directory as follows: SRCPV = "${@bb.fetch2.get_srcrev(d)}" Recipes that need to define PV do so with the help of the SRCPV. For example, the ofono recipe (ofono_git.bb) located in meta/recipes-connectivity in the Source Directory defines PV as follows: PV = "0.12-git${SRCPV}" SRCREV SRCREV[doc] = "The revision of the source code used to build the package. This variable applies to Subversion, Git, Mercurial and Bazaar only." The revision of the source code used to build the package. This variable applies to Subversion, Git, Mercurial and Bazaar only. Note that if you want to build a fixed revision and you want to avoid performing a query on the remote repository every time BitBake parses your recipe, you should specify a SRCREV that is a full revision identifier and not just a tag. For information on limitations when inheriting the latest revision of software using SRCREV, see the AUTOREV variable description and the "Automatically Incrementing a Binary Package Revision Number" section, which is in the Yocto Project Development Manual. SSTATE_DIR SSTATE_DIR[doc] = "The directory for the shared state cache." The directory for the shared state cache. SSTATE_MIRROR_ALLOW_NETWORK SSTATE_MIRROR_ALLOW_NETWORK[doc] = "If set to "1", allows fetches from mirrors that are specified in SSTATE_MIRRORS to work even when fetching from the network has been disabled by setting BB_NO_NETWORK to "1"." If set to "1", allows fetches from mirrors that are specified in SSTATE_MIRRORS to work even when fetching from the network has been disabled by setting BB_NO_NETWORK to "1". Using the SSTATE_MIRROR_ALLOW_NETWORK variable is useful if you have set SSTATE_MIRRORS to point to an internal server for your shared state cache, but you want to disable any other fetching from the network. SSTATE_MIRRORS SSTATE_MIRRORS[doc] = "Configures the OpenEmbedded build system to search other mirror locations for prebuilt cache data objects before building out the data. You can specify a filesystem directory or a remote URL such as HTTP or FTP." Configures the OpenEmbedded build system to search other mirror locations for prebuilt cache data objects before building out the data. This variable works like fetcher MIRRORS and PREMIRRORS and points to the cache locations to check for the shared objects. You can specify a filesystem directory or a remote URL such as HTTP or FTP. The locations you specify need to contain the shared state cache (sstate-cache) results from previous builds. The sstate-cache you point to can also be from builds on other machines. If a mirror uses the same structure as SSTATE_DIR, you need to add "PATH" at the end as shown in the examples below. The build system substitutes the correct path within the directory structure. SSTATE_MIRRORS ?= "\ file://.* http://someserver.tld/share/sstate/PATH;downloadfilename=PATH \n \ file://.* file:///some-local-dir/sstate/PATH" SSTATE_SCAN_FILES SSTATE_SCAN_FILES[doc] = "Controls the list of files the OpenEmbedded build system scans for hardcoded installation paths." Controls the list of files the OpenEmbedded build system scans for hardcoded installation paths. During a build, the OpenEmbedded build system creates a shared state (sstate) object during the first stage of preparing the sysroots. During the build, the object is scanned for hardcoded paths for original installation locations. The list of files that are scanned for paths is controlled by the SSTATE_SCAN_FILES variable. For details on the process, see the staging class. STAGING_BASE_LIBDIR_NATIVE STAGING_BASE_LIBDIR_NATIVE[doc] = "Specifies the path to the /lib subdirectory of the sysroot directory for the build host." Specifies the path to the /lib subdirectory of the sysroot directory for the build host. STAGING_BASELIBDIR STAGING_BASELIBDIR[doc] = "Specifies the path to the /lib subdirectory of the sysroot directory for the target for which the current recipe is being built (STAGING_DIR_HOST)." Specifies the path to the /lib subdirectory of the sysroot directory for the target for which the current recipe is being built (STAGING_DIR_HOST). STAGING_BINDIR STAGING_BINDIR[doc] = "Specifies the path to the /usr/bin subdirectory of the sysroot directory for the target for which the current recipe is being built (STAGING_DIR_HOST)." Specifies the path to the /usr/bin subdirectory of the sysroot directory for the target for which the current recipe is being built (STAGING_DIR_HOST). STAGING_BINDIR_CROSS STAGING_BINDIR_CROSS[doc] = "Specifies the path to the directory containing binary configuration scripts. These scripts provide configuration information for other software that wants to make use of libraries or include files provided by the software associated with the script." Specifies the path to the directory containing binary configuration scripts. These scripts provide configuration information for other software that wants to make use of libraries or include files provided by the software associated with the script. This style of build configuration has been largely replaced by pkg-config. Consequently, if pkg-config is supported by the library to which you are linking, it is recommended you use pkg-config instead of a provided configuration script. STAGING_BINDIR_NATIVE STAGING_BINDIR_NATIVE[doc] = "Specifies the path to the /usr/bin subdirectory of the sysroot directory for the build host." Specifies the path to the /usr/bin subdirectory of the sysroot directory for the build host. STAGING_DATADIR STAGING_DATADIR[doc] = "Specifies the path to the /usr/share subdirectory of the sysroot directory for the target for which the current recipe is being built (STAGING_DIR_HOST)." Specifies the path to the /usr/share subdirectory of the sysroot directory for the target for which the current recipe is being built (STAGING_DIR_HOST). STAGING_DATADIR_NATIVE STAGING_DATADIR_NATIVE[doc] = "Specifies the path to the /usr/share subdirectory of the sysroot directory for the build host." Specifies the path to the /usr/share subdirectory of the sysroot directory for the build host. STAGING_DIR STAGING_DIR[doc] = "Specifies the path to the top-level sysroots directory (i.e. ${TMPDIR}/sysroots)." Specifies the path to the top-level sysroots directory (i.e. ${TMPDIR}/sysroots). STAGING_DIR contains the directories that are staged into the sysroot by the do_populate_sysroot task. See the SYSROOT_DIRS variable and the "Sharing Files Between Recipes" section for more information. Recipes should never write files directly under the STAGING_DIR directory because the OpenEmbedded build system manages the directory automatically. Instead, files should be installed to ${D} within your recipe's do_install task and then the OpenEmbedded build system will stage a subset of those files into the sysroot. STAGING_DIR_HOST STAGING_DIR_HOST[doc] = "Specifies the path to the sysroot directory for the system that the component is built to run on." Specifies the path to the sysroot directory for the system that the component is built to run on (the system that hosts the component). For most recipes, this sysroot is the one that the recipe's do_populate_sysroot task copies files into. Exceptions include -native recipes, where the do_populate_sysroot task instead uses STAGING_DIR_NATIVE. Depending on the type of recipe and the build target, STAGING_DIR_HOST can have the following values: For recipes building for the target machine, the value is "${STAGING_DIR}/${MACHINE}". For native recipes building for the build host, the value is empty given the assumption that when building for the build host, the build host's own directories should be used. -native recipes are not installed into host paths like such as /usr. Rather, these recipes are installed into STAGING_DIR_NATIVE. When compiling -native recipes, standard build environment variables such as CPPFLAGS and CFLAGS are set up so that both host paths and STAGING_DIR_NATIVE are searched for libraries and headers using, for example, GCC's -isystem option. This emphasizes that the STAGING_DIR* variables should be viewed as input variables by tasks such as do_configure, do_compile, and do_install. Having the real system root correspond to STAGING_DIR_HOST makes conceptual sense for -native recipes, as they make use of host headers and libraries. STAGING_DIR_NATIVE STAGING_DIR_NATIVE[doc] = "Specifies the path to the sysroot directory used when building components that run on the build host itself." Specifies the path to the sysroot directory used when building components that run on the build host itself. STAGING_DIR_TARGET STAGING_DIR_TARGET[doc] = "Specifies the path to the sysroot used for the system for which the component generates code." Specifies the path to the sysroot used for the system for which the component generates code. For components that do not generate code, which is the majority, STAGING_DIR_TARGET is set to match STAGING_DIR_HOST. Some recipes build binaries that can run on the target system but those binaries in turn generate code for another different system (e.g. cross-canadian recipes). Using terminology from GNU, the primary system is referred to as the "HOST" and the secondary, or different, system is referred to as the "TARGET". Thus, the binaries run on the "HOST" system and generate binaries for the "TARGET" system. The STAGING_DIR_HOST variable points to the sysroot used for the "HOST" system, while STAGING_DIR_TARGET points to the sysroot used for the "TARGET" system. STAGING_ETCDIR_NATIVE STAGING_ETCDIR_NATIVE[doc] = "Specifies the path to the /etc subdirectory of the sysroot directory for the build host." Specifies the path to the /etc subdirectory of the sysroot directory for the build host. STAGING_EXECPREFIXDIR STAGING_EXECPREFIXDIR[doc] = "Specifies the path to the /usr subdirectory of the sysroot directory for the target for which the current recipe is being built (STAGING_DIR_HOST)." Specifies the path to the /usr subdirectory of the sysroot directory for the target for which the current recipe is being built (STAGING_DIR_HOST). STAGING_INCDIR STAGING_INCDIR[doc] = "Specifies the path to the /usr/include subdirectory of the sysroot directory for the target for which the current recipe being built (STAGING_DIR_HOST)." Specifies the path to the /usr/include subdirectory of the sysroot directory for the target for which the current recipe being built (STAGING_DIR_HOST). STAGING_INCDIR_NATIVE STAGING_INCDIR_NATIVE[doc] = "Specifies the path to the /usr/include subdirectory of the sysroot directory for the build host." Specifies the path to the /usr/include subdirectory of the sysroot directory for the build host. STAGING_KERNEL_BUILDDIR STAGING_KERNEL_BUILDDIR[doc] = "Points to the directory containing the kernel build artifacts." Points to the directory containing the kernel build artifacts. Recipes building software that needs to access kernel build artifacts (e.g. systemtap-uprobes) can look in the directory specified with the STAGING_KERNEL_BUILDDIR variable to find these artifacts after the kernel has been built. STAGING_KERNEL_DIR STAGING_KERNEL_DIR[doc] = "The directory with kernel headers that are required to build out-of-tree modules." The directory with kernel headers that are required to build out-of-tree modules. STAGING_LIBDIR STAGING_LIBDIR[doc] = "Specifies the path to the /usr/lib subdirectory of the sysroot directory for the target for which the current recipe is being built (STAGING_DIR_HOST)." Specifies the path to the /usr/lib subdirectory of the sysroot directory for the target for which the current recipe is being built (STAGING_DIR_HOST). STAGING_LIBDIR_NATIVE STAGING_LIBDIR_NATIVE[doc] = "Specifies the path to the /usr/lib subdirectory of the sysroot directory for the build host." Specifies the path to the /usr/lib subdirectory of the sysroot directory for the build host. STAMP STAMP[doc] = "Specifies the base path used to create recipe stamp files. The path to an actual stamp file is constructed by evaluating this string and then appending additional information." Specifies the base path used to create recipe stamp files. The path to an actual stamp file is constructed by evaluating this string and then appending additional information. Currently, the default assignment for STAMP as set in the meta/conf/bitbake.conf file is: STAMP = "${STAMPS_DIR}/${MULTIMACH_TARGET_SYS}/${PN}/${EXTENDPE}${PV}-${PR}" For information on how BitBake uses stamp files to determine if a task should be rerun, see the "Stamp Files and the Rerunning of Tasks" section. See STAMPS_DIR, MULTIMACH_TARGET_SYS, PN, EXTENDPE, PV, and PR for related variable information. STAMPS_DIR STAMPS_DIR[doc] = "Specifies the base directory in which the OpenEmbedded build system places stamps." Specifies the base directory in which the OpenEmbedded build system places stamps. The default directory is ${TMPDIR}/stamps. STRIP STRIP[doc] = "Minimal command and arguments to run 'strip' (strip symbols)." The minimal command and arguments to run strip, which is used to strip symbols. SUMMARY SUMMARY[doc] = "The short (80 characters or less) summary of the binary package for packaging systems such as opkg, rpm or dpkg. By default, SUMMARY is used to define the DESCRIPTION variable if DESCRIPTION is not set in the recipe." The short (72 characters or less) summary of the binary package for packaging systems such as opkg, rpm or dpkg. By default, SUMMARY is used to define the DESCRIPTION variable if DESCRIPTION is not set in the recipe. SVNDIR SVNDIR[doc] = "The directory where Subversion checkouts will be stored." The directory in which files checked out of a Subversion system are stored. SYSLINUX_DEFAULT_CONSOLE SYSLINUX_DEFAULT_CONSOLE[doc] = "Specifies the kernel boot default console." Specifies the kernel boot default console. If you want to use a console other than the default, set this variable in your recipe as follows where "X" is the console number you want to use: SYSLINUX_DEFAULT_CONSOLE = "console=ttyX" The syslinux class initially sets this variable to null but then checks for a value later. SYSLINUX_OPTS SYSLINUX_OPTS[doc] = "Lists additional options to add to the syslinux file." Lists additional options to add to the syslinux file. You need to set this variable in your recipe. If you want to list multiple options, separate the options with a semicolon character (;). The syslinux class uses this variable to create a set of options. SYSLINUX_SERIAL SYSLINUX_SERIAL[doc] = "Specifies the alternate serial port or turns it off." Specifies the alternate serial port or turns it off. To turn off serial, set this variable to an empty string in your recipe. The variable's default value is set in the syslinux as follows: SYSLINUX_SERIAL ?= "0 115200" The class checks for and uses the variable as needed. SYSLINUX_SPLASH SYSLINUX_SPLASH[doc] = "An .LSS file used as the background for the VGA boot menu when you are using the boot menu." An .LSS file used as the background for the VGA boot menu when you are using the boot menu. You need to set this variable in your recipe. The syslinux class checks for this variable and if found, the OpenEmbedded build system installs the splash screen. SYSLINUX_SERIAL_TTY SYSLINUX_SERIAL_TTY[doc] = "Specifies the alternate console=tty... kernel boot argument." Specifies the alternate console=tty... kernel boot argument. The variable's default value is set in the syslinux as follows: SYSLINUX_SERIAL_TTY ?= "console=ttyS0,115200" The class checks for and uses the variable as needed. SYSROOT_DIRS SYSROOT_DIRS[doc] = "Directories that are staged into the sysroot by the do_populate_sysroot task." Directories that are staged into the sysroot by the do_populate_sysroot task. By default, the following directories are staged: SYSROOT_DIRS = " \ ${includedir} \ ${libdir} \ ${base_libdir} \ ${nonarch_base_libdir} \ ${datadir} \ " SYSROOT_DIRS_BLACKLIST SYSROOT_DIRS_BLACKLIST[doc] = "Directories that are not staged into the sysroot by the do_populate_sysroot task." Directories that are not staged into the sysroot by the do_populate_sysroot task. You can use this variable to exclude certain subdirectories of directories listed in SYSROOT_DIRS from staging. By default, the following directories are not staged: SYSROOT_DIRS_BLACKLIST = " \ ${mandir} \ ${docdir} \ ${infodir} \ ${datadir}/locale \ ${datadir}/applications \ ${datadir}/fonts \ ${datadir}/pixmaps \ " SYSROOT_DIRS_NATIVE SYSROOT_DIRS_NATIVE[doc] = "Extra directories staged into the sysroot by the do_populate_sysroot task for -native recipes, in addition to those specified in SYSROOT_DIRS." Extra directories staged into the sysroot by the do_populate_sysroot task for -native recipes, in addition to those specified in SYSROOT_DIRS. By default, the following extra directories are staged: SYSROOT_DIRS_NATIVE = " \ ${bindir} \ ${sbindir} \ ${base_bindir} \ ${base_sbindir} \ ${libexecdir} \ ${sysconfdir} \ ${localstatedir} \ " Programs built by -native recipes run directly from the sysroot (STAGING_DIR_NATIVE), which is why additional directories containing program executables and supporting files need to be staged. SYSROOT_PREPROCESS_FUNCS SYSROOT_PREPROCESS_FUNCS[doc] = "A list of functions to execute after files are staged into the sysroot. These functions are usually used to apply additional processing on the staged files, or to stage additional files." A list of functions to execute after files are staged into the sysroot. These functions are usually used to apply additional processing on the staged files, or to stage additional files. SYSTEMD_AUTO_ENABLE SYSTEMD_AUTO_ENABLE[doc] = "For recipes that inherit the systemd class, this variable specifies whether the service you have specified in SYSTEMD_SERVICE should be started automatically or not." When inheriting the systemd class, this variable specifies whether the service you have specified in SYSTEMD_SERVICE should be started automatically or not. By default, the service is enabled to automatically start at boot time. The default setting is in the systemd class as follows: SYSTEMD_AUTO_ENABLE ??= "enable" You can disable the service by setting the variable to "disable". SYSTEMD_BOOT_CFG SYSTEMD_BOOT_CFG[doc] = "When EFI_PROVIDER is set to "systemd-boot", the SYSTEMD_BOOT_CFG variable specifies the configuration file that should be used." When EFI_PROVIDER is set to "systemd-boot", the SYSTEMD_BOOT_CFG variable specifies the configuration file that should be used. By default, the systemd-boot class sets the SYSTEMD_BOOT_CFG as follows: SYSTEMD_BOOT_CFG ?= "${S}/loader.conf" For information on Systemd-boot, see the Systemd-boot documentation. SYSTEMD_BOOT_ENTRIES SYSTEMD_BOOT_ENTRIES[doc] = "When EFI_PROVIDER is set to "systemd-boot", the SYSTEMD_BOOT_ENTRIES variable specifies a list of entry files (*.conf) to be installed containing one boot entry per file." When EFI_PROVIDER is set to "systemd-boot", the SYSTEMD_BOOT_ENTRIES variable specifies a list of entry files (*.conf) to be installed containing one boot entry per file. By default, the systemd-boot class sets the SYSTEMD_BOOT_ENTRIES as follows: SYSTEMD_BOOT_ENTRIES ?= "" For information on Systemd-boot, see the Systemd-boot documentation. SYSTEMD_BOOT_TIMEOUT SYSTEMD_BOOT_TIMEOUT[doc] = "When EFI_PROVIDER is set to "systemd-boot", the SYSTEMD_BOOT_TIMEOUT variable specifies the boot menu timeout in seconds." When EFI_PROVIDER is set to "systemd-boot", the SYSTEMD_BOOT_TIMEOUT variable specifies the boot menu timeout in seconds. By default, the systemd-boot class sets the SYSTEMD_BOOT_TIMEOUT as follows: SYSTEMD_BOOT_TIMEOUT ?= "10" For information on Systemd-boot, see the Systemd-boot documentation. SYSTEMD_PACKAGES SYSTEMD_PACKAGES[doc] = "For recipes that inherit the systemd class, this variable locates the systemd unit files when they are not found in the main recipe's package." When inheriting the systemd class, this variable locates the systemd unit files when they are not found in the main recipe's package. By default, the SYSTEMD_PACKAGES variable is set such that the systemd unit files are assumed to reside in the recipes main package: SYSTEMD_PACKAGES ?= "${PN}" If these unit files are not in this recipe's main package, you need to use SYSTEMD_PACKAGES to list the package or packages in which the build system can find the systemd unit files. SYSTEMD_SERVICE SYSTEMD_SERVICE[doc] = "For recipes that inherit the systemd class, this variable specifies the systemd service name for a package." When inheriting the systemd class, this variable specifies the systemd service name for a package. When you specify this file in your recipe, use a package name override to indicate the package to which the value applies. Here is an example from the connman recipe: SYSTEMD_SERVICE_${PN} = "connman.service" SYSVINIT_ENABLED_GETTYS SYSVINIT_ENABLED_GETTYS[doc] = "Specifies which virtual terminals should be running a getty, the default is '1'." When using SysVinit, specifies a space-separated list of the virtual terminals that should be running a getty (allowing login), assuming USE_VT is not set to "0". The default value for SYSVINIT_ENABLED_GETTYS is "1" (i.e. only run a getty on the first virtual terminal). T T[doc] = "This variable points to a directory were BitBake places temporary files, which consist mostly of task logs and scripts, when building a particular recipe." This variable points to a directory were BitBake places temporary files, which consist mostly of task logs and scripts, when building a particular recipe. The variable is typically set as follows: T = "${WORKDIR}/temp" The WORKDIR is the directory into which BitBake unpacks and builds the recipe. The default bitbake.conf file sets this variable. The T variable is not to be confused with the TMPDIR variable, which points to the root of the directory tree where BitBake places the output of an entire build. TARGET_ARCH TARGET_ARCH[doc] = "The architecture of the device being built. The OpenEmbedded build system supports the following architectures: arm, mips, ppc, x86, x86-64." The target machine's architecture. The OpenEmbedded build system supports many architectures. Here is an example list of architectures supported. This list is by no means complete as the architecture is configurable: arm i586 x86_64 powerpc powerpc64 mips mipsel For additional information on machine architectures, see the TUNE_ARCH variable. TARGET_AS_ARCH TARGET_AS_ARCH[doc] = "Specifies architecture-specific assembler flags for the target system." Specifies architecture-specific assembler flags for the target system. TARGET_AS_ARCH is initialized from TUNE_ASARGS by default in the BitBake configuration file (meta/conf/bitbake.conf): TARGET_AS_ARCH = "${TUNE_ASARGS}" TARGET_CC_ARCH TARGET_CC_ARCH[doc] = "Specifies architecture-specific C compiler flags for the target system." Specifies architecture-specific C compiler flags for the target system. TARGET_CC_ARCH is initialized from TUNE_CCARGS by default. It is a common workaround to append LDFLAGS to TARGET_CC_ARCH in recipes that build software for the target that would not otherwise respect the exported LDFLAGS variable. TARGET_CC_KERNEL_ARCH TARGET_CC_KERNEL_ARCH[doc] = "This is a specific kernel compiler flag for a CPU or Application Binary Interface (ABI) tune." This is a specific kernel compiler flag for a CPU or Application Binary Interface (ABI) tune. The flag is used rarely and only for cases where a userspace TUNE_CCARGS is not compatible with the kernel compilation. The TARGET_CC_KERNEL_ARCH variable allows the kernel (and associated modules) to use a different configuration. See the meta/conf/machine/include/arm/feature-arm-thumb.inc file in the Source Directory for an example. TARGET_CFLAGS TARGET_CFLAGS[doc] = "Flags passed to the C compiler for the target system. This variable evaluates to the same as CFLAGS." Specifies the flags to pass to the C compiler when building for the target. When building in the target context, CFLAGS is set to the value of this variable by default. Additionally, the SDK's environment setup script sets the CFLAGS variable in the environment to the TARGET_CFLAGS value so that executables built using the SDK also have the flags applied. TARGET_CPPFLAGS TARGET_CPPFLAGS[doc] = "Specifies the flags to pass to the C pre-processor (i.e. to both the C and the C++ compilers) when building for the target." Specifies the flags to pass to the C pre-processor (i.e. to both the C and the C++ compilers) when building for the target. When building in the target context, CPPFLAGS is set to the value of this variable by default. Additionally, the SDK's environment setup script sets the CPPFLAGS variable in the environment to the TARGET_CPPFLAGS value so that executables built using the SDK also have the flags applied. TARGET_CXXFLAGS TARGET_CXXFLAGS[doc] = "Specifies the flags to pass to the C++ compiler when building for the target." Specifies the flags to pass to the C++ compiler when building for the target. When building in the target context, CXXFLAGS is set to the value of this variable by default. Additionally, the SDK's environment setup script sets the CXXFLAGS variable in the environment to the TARGET_CXXFLAGS value so that executables built using the SDK also have the flags applied. TARGET_FPU TARGET_FPU[doc] = "Specifies the method for handling FPU code. For FPU-less targets, which include most ARM CPUs, the variable must be set to 'soft'. If not, the kernel emulation gets used, which results in a performance penalty." Specifies the method for handling FPU code. For FPU-less targets, which include most ARM CPUs, the variable must be set to "soft". If not, the kernel emulation gets used, which results in a performance penalty. TARGET_LD_ARCH TARGET_LD_ARCH[doc] = "Specifies architecture-specific linker flags for the target system." Specifies architecture-specific linker flags for the target system. TARGET_LD_ARCH is initialized from TUNE_LDARGS by default in the BitBake configuration file (meta/conf/bitbake.conf): TARGET_LD_ARCH = "${TUNE_LDARGS}" TARGET_LDFLAGS TARGET_LDFLAGS[doc] = "Specifies the flags to pass to the linker when building for the target." Specifies the flags to pass to the linker when building for the target. When building in the target context, LDFLAGS is set to the value of this variable by default. Additionally, the SDK's environment setup script sets the LDFLAGS variable in the environment to the TARGET_LDFLAGS value so that executables built using the SDK also have the flags applied. TARGET_OS TARGET_OS[doc] = "Specifies the target's operating system." Specifies the target's operating system. The variable can be set to "linux" for glibc-based systems and to "linux-uclibc" for uclibc. For ARM/EABI targets, there are also "linux-gnueabi" and "linux-uclibc-gnueabi" values possible. TARGET_PREFIX TARGET_PREFIX[doc] = "The prefix used for the toolchain binary target tools." Specifies the prefix used for the toolchain binary target tools. Depending on the type of recipe and the build target, TARGET_PREFIX is set as follows: For recipes building for the target machine, the value is "${TARGET_SYS}-". For native recipes, the build system sets the variable to the value of BUILD_PREFIX. For native SDK recipes (nativesdk), the build system sets the variable to the value of SDK_PREFIX. TARGET_SYS TARGET_SYS[doc] = "The target system is comprised of TARGET_ARCH,TARGET_VENDOR and TARGET_OS." Specifies the system, including the architecture and the operating system, for which the build is occurring in the context of the current recipe. The OpenEmbedded build system automatically sets this variable based on TARGET_ARCH, TARGET_VENDOR, and TARGET_OS variables. You do not need to set the TARGET_SYS variable yourself. Consider these two examples: Given a native recipe on a 32-bit, x86 machine running Linux, the value is "i686-linux". Given a recipe being built for a little-endian, MIPS target running Linux, the value might be "mipsel-linux". TARGET_VENDOR TARGET_VENDOR[doc] = "The name of the target vendor." Specifies the name of the target vendor. TCLIBCAPPEND TCLIBCAPPEND[doc] = "Specifies a suffix appended to TMPDIR that identifies the libc variant for the build." Specifies a suffix to be appended onto the TMPDIR value. The suffix identifies the libc variant for building. When you are building for multiple variants with the same Build Directory, this mechanism ensures that output for different libc variants is kept separate to avoid potential conflicts. In the defaultsetup.conf file, the default value of TCLIBCAPPEND is "-${TCLIBC}". However, distros such as poky, which normally only support one libc variant, set TCLIBCAPPEND to "" in their distro configuration file resulting in no suffix being applied. TCLIBC TCLIBC[doc] = "Specifies GNU standard C library (libc) variant to use during the build process. You can select 'glibc' or 'uclibc'." Specifies the GNU standard C library (libc) variant to use during the build process. This variable replaces POKYLIBC, which is no longer supported. You can select "glibc" or "uclibc". TCMODE TCMODE[doc] = "Enables an external toolchain (where provided by an additional layer) if set to a value other than 'default'." Specifies the toolchain selector. TCMODE controls the characteristics of the generated packages and images by telling the OpenEmbedded build system which toolchain profile to use. By default, the OpenEmbedded build system builds its own internal toolchain. The variable's default value is "default", which uses that internal toolchain. If TCMODE is set to a value other than "default", then it is your responsibility to ensure that the toolchain is compatible with the default toolchain. Using older or newer versions of these components might cause build problems. See the Release Notes for the specific components with which the toolchain must be compatible. The TCMODE variable is similar to TCLIBC, which controls the variant of the GNU standard C library (libc) used during the build process: glibc or uclibc. With additional layers, it is possible to use a pre-compiled external toolchain. One example is the Sourcery G++ Toolchain. The support for this toolchain resides in the separate Mentor Graphics meta-sourcery layer at . The layer's README file contains information on how to use the Sourcery G++ Toolchain as an external toolchain. In summary, you must be sure to add the layer to your bblayers.conf file in front of the meta layer and then set the EXTERNAL_TOOLCHAIN variable in your local.conf file to the location in which you installed the toolchain. The fundamentals used for this example apply to any external toolchain. You can use meta-sourcery as a template for adding support for other external toolchains. TEST_EXPORT_DIR TEST_EXPORT_DIR[doc] = "The location the OpenEmbedded build system uses to export tests when the TEST_EXPORT_ONLY variable is set to "1"." The location the OpenEmbedded build system uses to export tests when the TEST_EXPORT_ONLY variable is set to "1". The TEST_EXPORT_DIR variable defaults to "${TMPDIR}/testimage/${PN}". TEST_EXPORT_ONLY TEST_EXPORT_ONLY[doc] = "Specifies to export the tests only. Set this variable to "1" if you do not want to run the tests but you want them to be exported in a manner that you to run them outside of the build system." Specifies to export the tests only. Set this variable to "1" if you do not want to run the tests but you want them to be exported in a manner that you to run them outside of the build system. TEST_IMAGE TEST_IMAGE[doc] = "Enables test booting of virtual machine images under the QEMU emulator after any root filesystems are created and runs tests against those images." Automatically runs the series of automated tests for images when an image is successfully built. These tests are written in Python making use of the unittest module, and the majority of them run commands on the target system over ssh. You can set this variable to "1" in your local.conf file in the Build Directory to have the OpenEmbedded build system automatically run these tests after an image successfully builds: TEST_IMAGE = "1" For more information on enabling, running, and writing these tests, see the "Performing Automated Runtime Testing" section in the Yocto Project Development Manual and the "testimage*.bbclass" section. TEST_LOG_DIR TEST_LOG_DIR[doc] = "Holds the SSH log and the boot log for QEMU machines. The TEST_LOG_DIR variable defaults to "${WORKDIR}/testimage"." Holds the SSH log and the boot log for QEMU machines. The TEST_LOG_DIR variable defaults to "${WORKDIR}/testimage". Actual test results reside in the task log (log.do_testimage), which is in the ${WORKDIR}/temp/ directory. TEST_POWERCONTROL_CMD TEST_POWERCONTROL_CMD[doc] = "For automated hardware testing, specifies the command to use to control the power of the target machine under test" For automated hardware testing, specifies the command to use to control the power of the target machine under test. Typically, this command would point to a script that performs the appropriate action (e.g. interacting with a web-enabled power strip). The specified command should expect to receive as the last argument "off", "on" or "cycle" specifying to power off, on, or cycle (power off and then power on) the device, respectively. TEST_POWERCONTROL_EXTRA_ARGS TEST_POWERCONTROL_EXTRA_ARGS[doc] = "For automated hardware testing, specifies additional arguments to pass through to the command specified in TEST_POWERCONTROL_CMD" For automated hardware testing, specifies additional arguments to pass through to the command specified in TEST_POWERCONTROL_CMD. Setting TEST_POWERCONTROL_EXTRA_ARGS is optional. You can use it if you wish, for example, to separate the machine-specific and non-machine-specific parts of the arguments. TEST_QEMUBOOT_TIMEOUT TEST_QEMUBOOT_TIMEOUT[doc] = "The time in seconds allowed for an image to boot before automated runtime tests begin to run against an image." The time in seconds allowed for an image to boot before automated runtime tests begin to run against an image. The default timeout period to allow the boot process to reach the login prompt is 500 seconds. You can specify a different value in the local.conf file. For more information on testing images, see the "Performing Automated Runtime Testing" section in the Yocto Project Development Manual. TEST_SERIALCONTROL_CMD TEST_SERIALCONTROL_CMD[doc] = "For automated hardware testing, specifies the command to use to connect to the serial console of the target machine under test." For automated hardware testing, specifies the command to use to connect to the serial console of the target machine under test. This command simply needs to connect to the serial console and forward that connection to standard input and output as any normal terminal program does. For example, to use the Picocom terminal program on serial device /dev/ttyUSB0 at 115200bps, you would set the variable as follows: TEST_SERIALCONTROL_CMD = "picocom /dev/ttyUSB0 -b 115200" TEST_SERIALCONTROL_EXTRA_ARGS TEST_SERIALCONTROL_EXTRA_ARGS[doc] = "For automated hardware testing, specifies additional arguments to pass through to the command specified in TEST_SERIALCONTROL_CMD." For automated hardware testing, specifies additional arguments to pass through to the command specified in TEST_SERIALCONTROL_CMD. Setting TEST_SERIALCONTROL_EXTRA_ARGS is optional. You can use it if you wish, for example, to separate the machine-specific and non-machine-specific parts of the command. TEST_SERVER_IP TEST_SERVER_IP[doc] = "The IP address of the build machine (host machine). This IP address is usually automatically detected." The IP address of the build machine (host machine). This IP address is usually automatically detected. However, if detection fails, this variable needs to be set to the IP address of the build machine (i.e. where the build is taking place). The TEST_SERVER_IP variable is only used for a small number of tests such as the "dnf" test suite, which needs to download packages from WORKDIR/oe-rootfs-repo. TEST_TARGET TEST_TARGET[doc] = "For automated runtime testing, specifies the method of deploying the image and running tests on the target machine." Specifies the target controller to use when running tests against a test image. The default controller to use is "qemu": TEST_TARGET = "qemu" A target controller is a class that defines how an image gets deployed on a target and how a target is started. A layer can extend the controllers by adding a module in the layer's /lib/oeqa/controllers directory and by inheriting the BaseTarget class, which is an abstract class that cannot be used as a value of TEST_TARGET. You can provide the following arguments with TEST_TARGET: "qemu" and "QemuTarget": Boots a QEMU image and runs the tests. See the "Enabling Runtime Tests on QEMU" section in the Yocto Project Development Manual for more information. "simpleremote" and "SimpleRemoteTarget": Runs the tests on target hardware that is already up and running. The hardware can be on the network or it can be a device running an image on QEMU. You must also set TEST_TARGET_IP when you use "simpleremote" or "SimpleRemoteTarget". This argument is defined in meta/lib/oeqa/targetcontrol.py. The small caps names are kept for compatibility reasons. "GummibootTarget": Automatically deploys and runs tests on an EFI-enabled machine that has a master image installed. This argument is defined in meta/lib/oeqa/controllers/masterimage.py. For information on running tests on hardware, see the "Enabling Runtime Tests on Hardware" section in the Yocto Project Development Manual. TEST_TARGET_IP TEST_TARGET_IP[doc] = "The IP address of your hardware under test." The IP address of your hardware under test. The TEST_TARGET_IP variable has no effect when TEST_TARGET is set to "qemu". When you specify the IP address, you can also include a port. Here is an example: TEST_TARGET_IP = "192.168.1.4:2201" Specifying a port is useful when SSH is started on a non-standard port or in cases when your hardware under test is behind a firewall or network that is not directly accessible from your host and you need to do port address translation. TEST_SUITES TEST_SUITES[doc] = "An ordered list of tests (modules) to run against an image when performing automated runtime testing." An ordered list of tests (modules) to run against an image when performing automated runtime testing. The OpenEmbedded build system provides a core set of tests that can be used against images. Currently, there is only support for running these tests under QEMU. Tests include ping, ssh, df among others. You can add your own tests to the list of tests by appending TEST_SUITES as follows: TEST_SUITES_append = " mytest" Alternatively, you can provide the "auto" option to have all applicable tests run against the image. TEST_SUITES_append = " auto" Using this option causes the build system to automatically run tests that are applicable to the image. Tests that are not applicable are skipped. The order in which tests are run is important. Tests that depend on another test must appear later in the list than the test on which they depend. For example, if you append the list of tests with two tests (test_A and test_B) where test_B is dependent on test_A, then you must order the tests as follows: TEST_SUITES = " test_A test_B" For more information on testing images, see the "Performing Automated Runtime Testing" section in the Yocto Project Development Manual. THISDIR THISDIR[doc] = "The directory in which the file BitBake is currently parsing is located." The directory in which the file BitBake is currently parsing is located. Do not manually set this variable. TIME TIME[doc] = "The time the build was started using HMS format." The time the build was started. Times appear using the hour, minute, and second (HMS) format (e.g. "140159" for one minute and fifty-nine seconds past 1400 hours). TMPDIR TMPDIR[doc] = "The temporary directory the OpenEmbedded build system uses when it does its work building images. By default, the TMPDIR variable is named tmp within the Build Directory." This variable is the base directory the OpenEmbedded build system uses for all build output and intermediate files (other than the shared state cache). By default, the TMPDIR variable points to tmp within the Build Directory. If you want to establish this directory in a location other than the default, you can uncomment and edit the following statement in the conf/local.conf file in the Source Directory: #TMPDIR = "${TOPDIR}/tmp" An example use for this scenario is to set TMPDIR to a local disk, which does not use NFS, while having the Build Directory use NFS. The filesystem used by TMPDIR must have standard filesystem semantics (i.e. mixed-case files are unique, POSIX file locking, and persistent inodes). Due to various issues with NFS and bugs in some implementations, NFS does not meet this minimum requirement. Consequently, TMPDIR cannot be on NFS. TOOLCHAIN_HOST_TASK TOOLCHAIN_HOST_TASK[doc] = "This variable lists packages the OpenEmbedded build system uses when building an SDK, which contains a cross-development environment." This variable lists packages the OpenEmbedded build system uses when building an SDK, which contains a cross-development environment. The packages specified by this variable are part of the toolchain set that runs on the SDKMACHINE, and each package should usually have the prefix nativesdk-. For example, consider the following command when building an SDK: $ bitbake -c populate_sdk imagename In this case, a default list of packages is set in this variable, but you can add additional packages to the list. See the "Adding Individual Packages to the Standard SDK" section in the Yocto Project Software Development Kit (SDK) Developer's Guide for more information. For background information on cross-development toolchains in the Yocto Project development environment, see the "Cross-Development Toolchain Generation" section. For information on setting up a cross-development environment, see the Yocto Project Software Development Kit (SDK) Developer's Guide. TOOLCHAIN_OUTPUTNAME TOOLCHAIN_OUTPUTNAME[doc] = "Defines the name used for the toolchain output." This variable defines the name used for the toolchain output. The populate_sdk_base class sets the TOOLCHAIN_OUTPUTNAME variable as follows: TOOLCHAIN_OUTPUTNAME ?= "${SDK_NAME}-toolchain-${SDK_VERSION}" See the SDK_NAME and SDK_VERSION variables for additional information. TOOLCHAIN_TARGET_TASK TOOLCHAIN_TARGET_TASK[doc] = "This variable lists packages the OpenEmbedded build system uses when it creates the target part of an SDK, which includes libraries and headers." This variable lists packages the OpenEmbedded build system uses when it creates the target part of an SDK (i.e. the part built for the target hardware), which includes libraries and headers. Use this variable to add individual packages to the part of the SDK that runs on the target. See the "Adding Individual Packages to the Standard SDK" section in the Yocto Project Software Development Kit (SDK) Developer's Guide for more information. For background information on cross-development toolchains in the Yocto Project development environment, see the "Cross-Development Toolchain Generation" section. For information on setting up a cross-development environment, see the Yocto Project Software Development Kit (SDK) Developer's Guide. TOPDIR TOPDIR[doc] = "The Build Directory. BitBake automatically sets this variable. The OpenEmbedded build system uses the Build Directory when building images." The top-level Build Directory. BitBake automatically sets this variable when you initialize your build environment using either &OE_INIT_FILE; or oe-init-build-env-memres. TRANSLATED_TARGET_ARCH TRANSLATED_TARGET_ARCH[doc] = "A sanitized version of TARGET_ARCH. This variable is used where the architecture is needed in a value where underscores are not allowed." A sanitized version of TARGET_ARCH. This variable is used where the architecture is needed in a value where underscores are not allowed, for example within package filenames. In this case, dash characters replace any underscore characters used in TARGET_ARCH. Do not edit this variable. TUNE_ARCH TUNE_ARCH[doc] = "The GNU canonical architecture for a specific architecture (i.e. arm, armeb, mips, mips64, and so forth)." The GNU canonical architecture for a specific architecture (i.e. arm, armeb, mips, mips64, and so forth). BitBake uses this value to setup configuration. TUNE_ARCH definitions are specific to a given architecture. The definitions can be a single static definition, or can be dynamically adjusted. You can see details for a given CPU family by looking at the architecture's README file. For example, the meta/conf/machine/include/mips/README file in the Source Directory provides information for TUNE_ARCH specific to the mips architecture. TUNE_ARCH is tied closely to TARGET_ARCH, which defines the target machine's architecture. The BitBake configuration file (meta/conf/bitbake.conf) sets TARGET_ARCH as follows: TARGET_ARCH = "${TUNE_ARCH}" The following list, which is by no means complete since architectures are configurable, shows supported machine architectures: arm i586 x86_64 powerpc powerpc64 mips mipsel TUNE_ASARGS TUNE_ASARGS[doc] = "Specifies architecture-specific assembler flags for the target system." Specifies architecture-specific assembler flags for the target system. The set of flags is based on the selected tune features. TUNE_ASARGS is set using the tune include files, which are typically under meta/conf/machine/include/ and are influenced through TUNE_FEATURES. For example, the meta/conf/machine/include/x86/arch-x86.inc file defines the flags for the x86 architecture as follows: TUNE_ASARGS += "${@bb.utils.contains("TUNE_FEATURES", "mx32", "-x32", "", d)}" Board Support Packages (BSPs) select the tune. The selected tune, in turn, affects the tune variables themselves (i.e. the tune can supply its own set of flags). TUNE_CCARGS TUNE_CCARGS[doc] = "Specifies architecture-specific C compiler flags for the target system." Specifies architecture-specific C compiler flags for the target system. The set of flags is based on the selected tune features. TUNE_CCARGS is set using the tune include files, which are typically under meta/conf/machine/include/ and are influenced through TUNE_FEATURES. Board Support Packages (BSPs) select the tune. The selected tune, in turn, affects the tune variables themselves (i.e. the tune can supply its own set of flags). TUNE_LDARGS TUNE_LDARGS[doc] = "Specifies architecture-specific linker flags for the target system." Specifies architecture-specific linker flags for the target system. The set of flags is based on the selected tune features. TUNE_LDARGS is set using the tune include files, which are typically under meta/conf/machine/include/ and are influenced through TUNE_FEATURES. For example, the meta/conf/machine/include/x86/arch-x86.inc file defines the flags for the x86 architecture as follows: TUNE_LDARGS += "${@bb.utils.contains("TUNE_FEATURES", "mx32", "-m elf32_x86_64", "", d)}" Board Support Packages (BSPs) select the tune. The selected tune, in turn, affects the tune variables themselves (i.e. the tune can supply its own set of flags). TUNE_FEATURES TUNE_FEATURES[doc] = "Features used to "tune" a compiler for optimal use given a specific processor." Features used to "tune" a compiler for optimal use given a specific processor. The features are defined within the tune files and allow arguments (i.e. TUNE_*ARGS) to be dynamically generated based on the features. The OpenEmbedded build system verifies the features to be sure they are not conflicting and that they are supported. The BitBake configuration file (meta/conf/bitbake.conf) defines TUNE_FEATURES as follows: TUNE_FEATURES ??= "${TUNE_FEATURES_tune-${DEFAULTTUNE}}" See the DEFAULTTUNE variable for more information. TUNE_PKGARCH TUNE_PKGARCH[doc] = "The package architecture understood by the packaging system to define the architecture, ABI, and tuning of output packages." The package architecture understood by the packaging system to define the architecture, ABI, and tuning of output packages. The specific tune is defined using the "_tune" override as follows: TUNE_PKGARCH_tune-tune = "tune" These tune-specific package architectures are defined in the machine include files. Here is an example of the "core2-32" tuning as used in the meta/conf/machine/include/tune-core2.inc file: TUNE_PKGARCH_tune-core2-32 = "core2-32" TUNEABI TUNEABI[doc] = "An underlying ABI used by a particular tuning in a given toolchain layer. This feature allows providers using prebuilt libraries to check compatibility of a tuning against their selection of libraries." An underlying Application Binary Interface (ABI) used by a particular tuning in a given toolchain layer. Providers that use prebuilt libraries can use the TUNEABI, TUNEABI_OVERRIDE, and TUNEABI_WHITELIST variables to check compatibility of tunings against their selection of libraries. If TUNEABI is undefined, then every tuning is allowed. See the sanity class to see how the variable is used. TUNEABI_OVERRIDE TUNEABI_OVERRIDE[doc] = "If set, ignores TUNEABI_WHITELIST." If set, the OpenEmbedded system ignores the TUNEABI_WHITELIST variable. Providers that use prebuilt libraries can use the TUNEABI_OVERRIDE, TUNEABI_WHITELIST, and TUNEABI variables to check compatibility of a tuning against their selection of libraries. See the sanity class to see how the variable is used. TUNEABI_WHITELIST TUNEABI_WHITELIST[doc] = "A whitelist of permissible TUNEABI values. If the variable is not set, all values are allowed." A whitelist of permissible TUNEABI values. If TUNEABI_WHITELIST is not set, all tunes are allowed. Providers that use prebuilt libraries can use the TUNEABI_WHITELIST, TUNEABI_OVERRIDE, and TUNEABI variables to check compatibility of a tuning against their selection of libraries. See the sanity class to see how the variable is used. TUNECONFLICTS[feature] TUNECONFLICTS[doc] = "Specifies CPU or Application Binary Interface (ABI) tuning features that conflict with specified feature." Specifies CPU or Application Binary Interface (ABI) tuning features that conflict with feature. Known tuning conflicts are specified in the machine include files in the Source Directory. Here is an example from the meta/conf/machine/include/mips/arch-mips.inc include file that lists the "o32" and "n64" features as conflicting with the "n32" feature: TUNECONFLICTS[n32] = "o32 n64" TUNEVALID[feature] TUNEVALID[doc] = "Descriptions, stored as flags, of valid tuning features." Specifies a valid CPU or Application Binary Interface (ABI) tuning feature. The specified feature is stored as a flag. Valid features are specified in the machine include files (e.g. meta/conf/machine/include/arm/arch-arm.inc). Here is an example from that file: TUNEVALID[bigendian] = "Enable big-endian mode." See the machine include files in the Source Directory for these features. UBOOT_CONFIG UBOOT_CONFIG[doc] = "Configures the UBOOT_MACHINE and can also define IMAGE_FSTYPES for individual cases." Configures the UBOOT_MACHINE and can also define IMAGE_FSTYPES for individual cases. Following is an example from the meta-fsl-arm layer. UBOOT_CONFIG ??= "sd" UBOOT_CONFIG[sd] = "mx6qsabreauto_config,sdcard" UBOOT_CONFIG[eimnor] = "mx6qsabreauto_eimnor_config" UBOOT_CONFIG[nand] = "mx6qsabreauto_nand_config,ubifs" UBOOT_CONFIG[spinor] = "mx6qsabreauto_spinor_config" In this example, "sd" is selected as the configuration of the possible four for the UBOOT_MACHINE. The "sd" configuration defines "mx6qsabreauto_config" as the value for UBOOT_MACHINE, while the "sdcard" specifies the IMAGE_FSTYPES to use for the U-boot image. For more information on how the UBOOT_CONFIG is handled, see the uboot-config class. UBOOT_ENTRYPOINT UBOOT_ENTRYPOINT[doc] = "Specifies the entry point for the U-Boot image." Specifies the entry point for the U-Boot image. During U-Boot image creation, the UBOOT_ENTRYPOINT variable is passed as a command-line parameter to the uboot-mkimage utility. UBOOT_LOADADDRESS UBOOT_LOADADDRESS[doc] = "Specifies the load address for the U-Boot image." Specifies the load address for the U-Boot image. During U-Boot image creation, the UBOOT_LOADADDRESS variable is passed as a command-line parameter to the uboot-mkimage utility. UBOOT_LOCALVERSION UBOOT_LOCALVERSION[doc] = "Appends a string to the name of the local version of the U-Boot image." Appends a string to the name of the local version of the U-Boot image. For example, assuming the version of the U-Boot image built was "2013.10, the full version string reported by U-Boot would be "2013.10-yocto" given the following statement: UBOOT_LOCALVERSION = "-yocto" UBOOT_MACHINE UBOOT_MACHINE[doc] = "Specifies the value passed on the make command line when building a U-Boot image." Specifies the value passed on the make command line when building a U-Boot image. The value indicates the target platform configuration. You typically set this variable from the machine configuration file (i.e. conf/machine/machine_name.conf). Please see the "Selection of Processor Architecture and Board Type" section in the U-Boot README for valid values for this variable. UBOOT_MAKE_TARGET UBOOT_MAKE_TARGET[doc] = "Specifies the target called in the Makefile." Specifies the target called in the Makefile. The default target is "all". UBOOT_SUFFIX UBOOT_SUFFIX[doc] = "Points to the generated U-Boot extension." Points to the generated U-Boot extension. For example, u-boot.sb has a .sb extension. The default U-Boot extension is .bin UBOOT_TARGET UBOOT_TARGET[doc] = "Specifies the target used for building U-Boot." Specifies the target used for building U-Boot. The target is passed directly as part of the "make" command (e.g. SPL and AIS). If you do not specifically set this variable, the OpenEmbedded build process passes and uses "all" for the target during the U-Boot building process. UNKNOWN_CONFIGURE_WHITELIST UNKNOWN_CONFIGURE_WHITELIST[doc] = "Specifies a list of options that, if reported by the configure script as being invalid, should not generate a warning during the do_configure task." Specifies a list of options that, if reported by the configure script as being invalid, should not generate a warning during the do_configure task. Normally, invalid configure options are simply not passed to the configure script (e.g. should be removed from EXTRA_OECONF or PACKAGECONFIG_CONFARGS). However, common options, for example, exist that are passed to all configure scripts at a class level that might not be valid for some configure scripts. It follows that no benefit exists in seeing a warning about these options. For these cases, the options are added to UNKNOWN_CONFIGURE_WHITELIST. The configure arguments check that uses UNKNOWN_CONFIGURE_WHITELIST is part of the insane class and is only enabled if the recipe inherits the autotools class. UPDATERCPN UPDATERCPN[doc] = "Specifies the package that contains the initscript that is to be enabled." For recipes inheriting the update-rc.d class, UPDATERCPN specifies the package that contains the initscript that is to be enabled. The default value is "${PN}". Given that almost all recipes that install initscripts package them in the main package for the recipe, you rarely need to set this variable in individual recipes. UPSTREAM_CHECK_GITTAGREGEX UPSTREAM_CHECK_GITTAGREGEX[doc] = "Filters relevant Git tags when fetching source from an upstream Git repository." When the distrodata class is enabled globally, you can perform a per-recipe check for what the latest upstream source code version is by calling bitbake -c checkpkg recipe. If the recipe source code is provided from Git repositories, the OpenEmbedded build system determines the latest upstream version by picking the latest tag from the list of all repository tags. You can use the UPSTREAM_CHECK_GITTAGREGEX variable to provide a regular expression to filter only the relevant tags should the default filter not work correctly. UPSTREAM_CHECK_GITTAGREGEX = "git_tag_regex" UPSTREAM_CHECK_REGEX UPSTREAM_CHECK_REGEX[doc] = "The regular expression the package checking system uses to parse the page pointed to by UPSTREAM_CHECK_URI." When the distrodata class is enabled globally, use the UPSTREAM_CHECK_REGEX variable to specify a different regular expression instead of the default one when the package checking system is parsing the page found using UPSTREAM_CHECK_URI. UPSTREAM_CHECK_REGEX = "package_regex" UPSTREAM_CHECK_URI UPSTREAM_CHECK_URI[doc] = "The URL used by the package checking system to get the latest version of the package when source files are fetched from an upstream Git repository." When the distrodata class is enabled globally, you can perform a per-recipe check for what the latest upstream source code version is by calling bitbake -c checkpkg recipe. If the source code is provided from tarballs, the latest version is determined by fetching the directory listing where the tarball is and attempting to find a later tarball. When this approach does not work, you can use UPSTREAM_CHECK_URI to provide a different URI that contains the link to the latest tarball. UPSTREAM_CHECK_URI = "recipe_url" USE_DEVFS USE_DEVFS[doc] = "Determines if devtmpfs is used for /dev population." Determines if devtmpfs is used for /dev population. The default value used for USE_DEVFS is "1" when no value is specifically set. Typically, you would set USE_DEVFS to "0" for a statically populated /dev directory. See the "Selecting a Device Manager" section in the Yocto Project Development Manual for information on how to use this variable. USE_VT USE_VT[doc] = "When using SysVinit, determines whether or not to run a getty on any virtual terminals in order to enable logging in through those terminals." When using SysVinit, determines whether or not to run a getty on any virtual terminals in order to enable logging in through those terminals. The default value used for USE_VT is "1" when no default value is specifically set. Typically, you would set USE_VT to "0" in the machine configuration file for machines that do not have a graphical display attached and therefore do not need virtual terminal functionality. USER_CLASSES USER_CLASSES[doc] = "List of additional classes to use when building images that enable extra features." A list of classes to globally inherit. These classes are used by the OpenEmbedded build system to enable extra features (e.g. buildstats, image-mklibs, and so forth). The default list is set in your local.conf file: USER_CLASSES ?= "buildstats image-mklibs image-prelink" For more information, see meta-poky/conf/local.conf.sample in the Source Directory. USERADD_ERROR_DYNAMIC USERADD_ERROR_DYNAMIC[doc] = "If set to 'error', forces the OpenEmbedded build system to produce an error if the user identification (uid) and group identification (gid) values are not defined in files/passwd and files/group files. If set to 'warn', a warning will be issued instead." If set to "error", forces the OpenEmbedded build system to produce an error if the user identification (uid) and group identification (gid) values are not defined in files/passwd and files/group files. If set to "warn", a warning will be issued instead. The default behavior for the build system is to dynamically apply uid and gid values. Consequently, the USERADD_ERROR_DYNAMIC variable is by default not set. If you plan on using statically assigned gid and uid values, you should set the USERADD_ERROR_DYNAMIC variable in your local.conf file as follows: USERADD_ERROR_DYNAMIC = "error" Overriding the default behavior implies you are going to also take steps to set static uid and gid values through use of the USERADDEXTENSION, USERADD_UID_TABLES, and USERADD_GID_TABLES variables. USERADD_GID_TABLES USERADD_GID_TABLES[doc] = "Specifies a password file to use for obtaining static group identification (gid) values when the OpenEmbedded build system adds a group to the system during package installation." Specifies a password file to use for obtaining static group identification (gid) values when the OpenEmbedded build system adds a group to the system during package installation. When applying static group identification (gid) values, the OpenEmbedded build system looks in BBPATH for a files/group file and then applies those uid values. Set the variable as follows in your local.conf file: USERADD_GID_TABLES = "files/group" Setting the USERADDEXTENSION variable to "useradd-staticids" causes the build system to use static gid values. USERADD_PACKAGES USERADD_PACKAGES[doc] = "When a recipe inherits the useradd class, this variable specifies the individual packages within the recipe that require users and/or groups to be added." When inheriting the useradd class, this variable specifies the individual packages within the recipe that require users and/or groups to be added. You must set this variable if the recipe inherits the class. For example, the following enables adding a user for the main package in a recipe: USERADD_PACKAGES = "${PN}" If follows that if you are going to use the USERADD_PACKAGES variable, you need to set one or more of the USERADD_PARAM, GROUPADD_PARAM, or GROUPMEMS_PARAM variables. USERADD_PARAM USERADD_PARAM[doc] = "When a recipe inherits the useradd class, this variable specifies for a package what parameters should be passed to the useradd command if you wish to add a user to the system when the package is installed." When inheriting the useradd class, this variable specifies for a package what parameters should be passed to the useradd command if you wish to add a user to the system when the package is installed. Here is an example from the dbus recipe: USERADD_PARAM_${PN} = "--system --home ${localstatedir}/lib/dbus \ --no-create-home --shell /bin/false \ --user-group messagebus" For information on the standard Linux shell command useradd, see . USERADD_UID_TABLES USERADD_UID_TABLES[doc] = "Specifies a password file to use for obtaining static user identification (uid) values when the OpenEmbedded build system adds a user to the system during package installation." Specifies a password file to use for obtaining static user identification (uid) values when the OpenEmbedded build system adds a user to the system during package installation. When applying static user identification (uid) values, the OpenEmbedded build system looks in BBPATH for a files/passwd file and then applies those uid values. Set the variable as follows in your local.conf file: USERADD_UID_TABLES = "files/passwd" Setting the USERADDEXTENSION variable to "useradd-staticids" causes the build system to use static uid values. USERADDEXTENSION USERADDEXTENSION[doc] = "When set to 'useradd-staticids', causes the OpenEmbedded build system to base all user and group additions on a static passwd and group files found in BBPATH." When set to "useradd-staticids", causes the OpenEmbedded build system to base all user and group additions on a static passwd and group files found in BBPATH. To use static user identification (uid) and group identification (gid) values, set the variable as follows in your local.conf file: USERADDEXTENSION = "useradd-staticids" Setting this variable to use static uid and gid values causes the OpenEmbedded build system to employ the useradd-staticids class. If you use static uid and gid information, you must also specify the files/passwd and files/group files by setting the USERADD_UID_TABLES and USERADD_GID_TABLES variables. Additionally, you should also set the USERADD_ERROR_DYNAMIC variable. VOLATILE_LOG_DIR VOLATILE_LOG_DIR[doc] = "Specifies the persistence of the target's /var/log directory, which is used to house postinstall target log files." Specifies the persistence of the target's /var/log directory, which is used to house postinstall target log files. By default, VOLATILE_LOG_DIR is set to "yes", which means the file is not persistent. You can override this setting by setting the variable to "no" to make the log directory persistent. WARN_QA WARN_QA[doc] = "Specifies the quality assurance checks whose failures are reported as warnings by the OpenEmbedded build system." Specifies the quality assurance checks whose failures are reported as warnings by the OpenEmbedded build system. You set this variable in your distribution configuration file. For a list of the checks you can control with this variable, see the "insane.bbclass" section. WKS_FILE_DEPENDS WKS_FILE_DEPENDS[doc] = "Lists a recipe's build-time dependencies specific to Wic." When placed in the recipe that builds your image, this variable lists build-time dependencies. The WKS_FILE_DEPENDS variable is only applicable when Wic images are active (i.e. when IMAGE_FSTYPES contains entries related to Wic). If your recipe does not create Wic images, the variable has no effect. The WKS_FILE_DEPENDS variable is similar to the DEPENDS variable. When you use the variable in your recipe that builds the Wic image, dependencies you list in the WIC_FILE_DEPENDS variable are added to the DEPENDS variable. With the WKS_FILE_DEPENDS variable, you have the possibility to specify a list of additional dependencies (e.g. native tools, bootloaders, and so forth), that are required to build Wic images. Following is an example: WKS_FILE_DEPENDS = "some-native-tool" In the previous example, some-native-tool would be replaced with an actual native tool on which the build would depend. WKS_FILE WKS_FILE[doc] = "Specifies the name of the wic kickstart file." Specifies the location of the Wic kickstart file that is used by the OpenEmbedded build system to create a partitioned image (image.wic). For information on how to create a partitioned image, see the "Creating Partitioned Images" section. For details on the kickstart file format, see the "OpenEmbedded Kickstart (.wks) Reference. WORKDIR WORKDIR[doc] = "The pathname of the working directory in which the OpenEmbedded build system builds a recipe. This directory is located within the TMPDIR directory structure and changes as different packages are built." The pathname of the work directory in which the OpenEmbedded build system builds a recipe. This directory is located within the TMPDIR directory structure and is specific to the recipe being built and the system for which it is being built. The WORKDIR directory is defined as follows: ${TMPDIR}/work/${MULTIMACH_TARGET_SYS}/${PN}/${EXTENDPE}${PV}-${PR} The actual directory depends on several things: TMPDIR: The top-level build output directory MULTIMACH_TARGET_SYS: The target system identifier PN: The recipe name EXTENDPE: The epoch - (if PE is not specified, which is usually the case for most recipes, then EXTENDPE is blank) PV: The recipe version PR: The recipe revision As an example, assume a Source Directory top-level folder name poky, a default Build Directory at poky/build, and a qemux86-poky-linux machine target system. Furthermore, suppose your recipe is named foo_1.3.0-r0.bb. In this case, the work directory the build system uses to build the package would be as follows: poky/build/tmp/work/qemux86-poky-linux/foo/1.3.0-r0 XSERVER XSERVER[doc] = "Specifies the packages that should be installed to provide an X server and drivers for the current machine." Specifies the packages that should be installed to provide an X server and drivers for the current machine, assuming your image directly includes packagegroup-core-x11-xserver or, perhaps indirectly, includes "x11-base" in IMAGE_FEATURES. The default value of XSERVER, if not specified in the machine configuration, is "xserver-xorg xf86-video-fbdev xf86-input-evdev".