Table of Contents
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 N O P R S T U V W X
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"
Specifies whether to produce an output package even 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"
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.
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/
.
ALTERNATIVE_LINK_NAME
is not
defined, it defaults to
${bindir}/name
.
For more information on the alternatives system, see the
"update-alternatives.bbclass
"
section.
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.
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.
An override list of append strings for each target
specified with
LABELS
.
See the
grub-efi
class for more information on how this variable is used.
The minimal command and arguments used to run
ar
.
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.
The minimal command and arguments used to run the assembler.
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
.
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"
The email address used to contact the original author or authors in order to send patches and forward bugs.
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.
Enables creating an automatic menu for the syslinux
bootloader.
You must set this variable in your recipe.
The
syslinux
class checks this variable.
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
${SRCPV}
.
For more information see the "Automatically Incrementing a Binary Package Revision Number" section in the Yocto Project Development Tasks Manual.
The list of defined CPU and Application Binary Interface (ABI) tunings (i.e. "tunes") available for use by the OpenEmbedded build system.
The list simply presents the tunes that are available. Not all tunes may be compatible with a particular machine configuration, or with each other in a Multilib configuration.
To add a tune to the list, be sure to append it with spaces using the "+=" BitBake operator. Do not simply replace the list by using the "=" operator. See the "Basic Syntax" section in the BitBake User Manual for more information.
The directory within the
Build Directory
in which the OpenEmbedded build system places generated
objects during a recipe's build process.
By default, this directory is the same as the S
directory, which is defined as:
S = "${WORKDIR}/${BP}"
You can separate the (S
) directory
and the directory pointed to by the B
variable.
Most Autotools-based recipes support separating these
directories.
The build system defaults to using separate directories for
gcc
and some kernel recipes.
Lists "recommended-only" packages to not install.
Recommended-only packages are packages installed only
through the
RRECOMMENDS
variable.
You can prevent any of these "recommended" packages from
being installed by listing them with the
BAD_RECOMMENDATIONS
variable:
BAD_RECOMMENDATIONS = "package_name
package_name
package_name
..."
You can set this variable globally in your
local.conf
file or you can attach it to
a specific image recipe by using the recipe name override:
BAD_RECOMMENDATIONS_pn-target_image
= "package_name
"
It is important to realize that if you choose to not install
packages using this variable and some other packages are
dependent on them (i.e. listed in a recipe's
RDEPENDS
variable), the OpenEmbedded build system ignores your
request and will install the packages to avoid dependency
errors.
Support for this variable exists only when using the IPK and RPM packaging backend. Support does not exist for DEB.
See the
NO_RECOMMENDATIONS
and the
PACKAGE_EXCLUDE
variables for related information.
The library directory name for the CPU or Application
Binary Interface (ABI) tune.
The BASE_LIB
applies only in the
Multilib context.
See the
"Combining Multiple Versions of Library Files into One Image"
section in the Yocto Project Development Tasks Manual for
information on Multilib.
The BASE_LIB
variable is defined in
the machine include files in the
Source Directory.
If Multilib is not being used, the value defaults to "lib".
Points to the base of the work directory for all recipes. The default value is "${TMPDIR}/work".
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"
The use of the "*
"
character only works at the beginning of
a host name and it must be isolated from
the remainder of the host name.
You cannot use the wildcard character in any
other location of the name or combined with
the front part of the name.
For example,
*.foo.bar
is supported,
while *aa.foo.bar
is not.
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.
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"
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 ${TMPDIR}
directory
drops below 100 Kbytes.
No disk space monitoring for the directory itself occurs
in this case.
Defines the disk space and free inode warning intervals.
To set these intervals, define the variable in your
conf/local.conf
file in the
Build Directory.
If you are going to use the
BB_DISKMON_WARNINTERVAL
variable, you must
also use the
BB_DISKMON_DIRS
variable
and define its action as "WARN".
During the build, subsequent warnings are issued each time
disk space or number of free inodes further reduces by
the respective interval.
If you do not provide a BB_DISKMON_WARNINTERVAL
variable and you do use BB_DISKMON_DIRS
with
the "WARN" action, the disk monitoring interval defaults to
the following:
BB_DISKMON_WARNINTERVAL = "50M,5K"
When specifying the variable in your configuration file, use the following form:
BB_DISKMON_WARNINTERVAL = "disk_space_interval
,disk_inode_interval
" where:disk_space_interval
is: An interval of memory expressed in either G, M, or K for Gbytes, Mbytes, or Kbytes, respectively. You cannot use GB, MB, or KB.disk_inode_interval
is: An interval of free inodes expressed in either G, M, or K for Gbytes, Mbytes, or Kbytes, respectively. You cannot use GB, MB, or KB.
Here is an example:
BB_DISKMON_DIRS = "WARN,${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).
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.
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 a Build" section in the Yocto Project Development Tasks Manual.
Specifies the time (in seconds) after which to unload the
BitBake server due to inactivity.
Set BB_SERVER_TIMEOUT
to determine how
long the BitBake server stays resident between invocations.
For example, the following statement in your
local.conf
file instructs the server
to be unloaded after 20 seconds of inactivity:
BB_SERVER_TIMEOUT = "20"
If you want the server to never be unloaded, set
BB_SERVER_TIMEOUT
to "-1".
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.
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.
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
).
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).
bitbake-layers show-layers
to list
all configured layers along with their priorities.
A space-separated list of recipe files BitBake uses to build software.
When specifying recipe files, you can pattern match using
Python's
glob
syntax.
For details on the syntax, see the documentation by
following the previous link.
Activates content when identified layers are present. You identify the layers by the collections that the layers define.
Use the BBFILES_DYNAMIC
variable to
avoid .bbappend
files whose
corresponding .bb
file is in a layer
that attempts to modify other layers through
.bbappend
but does not want to
introduce a hard dependency on those other layers.
Use the following form for
BBFILES_DYNAMIC
:
collection_name
:filename_pattern
The following example identifies two collection names and two filename patterns:
BBFILES_DYNAMIC += " \ clang-layer:${LAYERDIR}/bbappends/meta-clang/*/*/*.bbappend \ core:${LAYERDIR}/bbappends/openembedded-core/meta/*/*/*.bbappend \ "
This next example shows an error message that occurs because invalid entries are found, which cause parsing to abort:
ERROR: BBFILES_DYNAMIC entries must be of the form <collection name>:<filename pattern>, not: /work/my-layer/bbappends/meta-security-isafw/*/*/*.bbappend /work/my-layer/bbappends/openembedded-core/meta/*/*/*.bbappend
Variable that controls how BitBake displays logs on build 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.
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
.
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. Consequently, the syntax follows Python's Regular Expression (re) syntax. The expressions are compared against the full paths to the files. For complete syntax information, see Python's documentation at http://docs.python.org/3/library/re.html#re.
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"
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
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 Images for Multiple Targets Using Multiple Configurations"
section in the Yocto Project Development Tasks Manual.
Used by BitBake to locate
.bbclass
and configuration files.
This variable is analogous to the
PATH
variable.
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 $ bitbaketarget
If defined in the BitBake environment,
BBSERVER
points to the BitBake
remote server.
Use the following format to export the variable to the BitBake environment:
export BBSERVER=localhost:$port"
By default, BBSERVER
also appears in
BB_HASHBASE_WHITELIST
.
Consequently, BBSERVER
is excluded
from checksum and dependency data.
When inheriting the
binconfig-disabled
class, this variable specifies binary configuration
scripts to disable in favor of using
pkg-config
to query the information.
The binconfig-disabled
class will
modify the specified scripts to return an error so that
calls to them can be easily found and replaced.
To add multiple scripts, separate them by spaces.
Here is an example from the libpng
recipe:
BINCONFIG = "${bindir}/libpng-config ${bindir}/libpng16-config"
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.
BINCONFIG_GLOB
variable
uses
shell globbing,
which is recognition and expansion of wildcards during
pattern matching.
Shell globbing is very similar to
fnmatch
and
glob
.
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.
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}
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.
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.
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.
Specifies the architecture-specific assembler flags for
the build host. By default, the value of
BUILD_AS_ARCH
is empty.
Specifies the architecture-specific C compiler flags for
the build host. By default, the value of
BUILD_CC_ARCH
is empty.
Specifies the linker command to be used for the build host
when the C compiler is being used as the linker. By default,
BUILD_CCLD
points to GCC and passes as
arguments the value of
BUILD_CC_ARCH
,
assuming BUILD_CC_ARCH
is set.
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.
Specifies the flags to pass to the C preprocessor
(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.
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.
Specifies the Fortran compiler command for the build host.
By default, BUILD_FC
points to
Gfortran and passes as arguments the value of
BUILD_CC_ARCH
,
assuming BUILD_CC_ARCH
is set.
Specifies the linker command for the build host. By default,
BUILD_LD
points to the GNU linker (ld)
and passes as arguments the value of
BUILD_LD_ARCH
,
assuming BUILD_LD_ARCH
is set.
Specifies architecture-specific linker flags for the build
host. By default, the value of
BUILD_LD_ARCH
is empty.
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.
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".
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.
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.
Specifies the command to be used to strip debugging symbols
from binaries produced for the build host. By default,
BUILD_STRIP
points to
${
BUILD_PREFIX
}strip
.
Specifies the system, including the architecture and
the operating system, to use when building for the build
host (i.e. when building native
recipes).
The OpenEmbedded build system automatically sets this
variable based on
BUILD_ARCH
,
BUILD_VENDOR
,
and
BUILD_OS
.
You do not need to set the BUILD_SYS
variable yourself.
Specifies the vendor name to use when building for the build host. The default value is an empty string ("").
Points to the location of the
Build Directory.
You can define this directory indirectly through the
oe-init-build-env
script by passing in a Build Directory path when you run
the script.
If you run the script and do not provide a Build Directory
path, the BUILDDIR
defaults to
build
in the current directory.
When inheriting the
buildhistory
class, this variable specifies whether or not to commit the
build history output in a local Git repository.
If set to "1", this local repository will be maintained
automatically by the
buildhistory
class and a commit will be created on every
build for changes to each top-level subdirectory of the
build history output (images, packages, and sdk).
If you want to track changes to build history over
time, you should set this value to "1".
By default, the buildhistory
class
does not commit the build history output in a local
Git repository:
BUILDHISTORY_COMMIT ?= "0"
When inheriting the
buildhistory
class, this variable specifies the author to use for each
Git commit.
In order for the BUILDHISTORY_COMMIT_AUTHOR
variable to work, the
BUILDHISTORY_COMMIT
variable must be set to "1".
Git requires that the value you provide for the
BUILDHISTORY_COMMIT_AUTHOR
variable
takes the form of "name email@host
".
Providing an email address or host that is not valid does
not produce an error.
By default, the buildhistory
class
sets the variable as follows:
BUILDHISTORY_COMMIT_AUTHOR ?= "buildhistory <buildhistory@${DISTRO}>"
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"
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 in the Yocto Project Development Tasks Manual.
You can specify these 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).
task: Save output file signatures for shared state (sstate) tasks. This saves one file per task and lists the SHA-256 checksums for each file staged (i.e. the output of the task).
By default, the buildhistory
class
enables the following features:
BUILDHISTORY_FEATURES ?= "image package sdk"
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"
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 ?= ""
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.
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.
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.
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.
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/
.
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.
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.
The minimal command and arguments used to run 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 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-
)
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
.
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.
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.
Points to meta/files/common-licenses
in the
Source Directory,
which is where generic license files reside.
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.
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.
Defines wildcards to match when installing a list of complementary packages for all the packages explicitly (or implicitly) installed in an image.
COMPLEMENTARY_GLOB
variable
uses Unix filename pattern matching
(fnmatch
),
which is similar to the Unix style pathname pattern
expansion
(glob
).
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'
Stores sysroot components for each recipe.
The OpenEmbedded build system uses
COMPONENTS_DIR
when constructing
recipe-specific sysroots for other recipes.
The default is
"${
STAGING_DIR
}-components
."
(i.e. "${
TMPDIR
}/sysroots-components
").
Tracks the version of the local configuration file
(i.e. local.conf
).
The value for CONF_VERSION
increments each time build/conf/
compatibility changes.
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.
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.
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 Tasks Manual.
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
.
The minimal arguments for GNU configure.
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.
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.
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.
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*".
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.
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.
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.
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.
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 Tasks Manual
for information on providing license text.
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.
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 Tasks Manual
for information on providing license text.
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.
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.
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.
The minimal command and arguments used to run the C preprocessor.
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-
)
The toolchain binary prefix for the target tools.
The CROSS_COMPILE
variable is the
same as the
TARGET_PREFIX
variable.
CROSS_COMPILE
variable only in
certain contexts (e.g. when building for kernel
and kernel module recipes).
The directory in which files checked out under the CVS system are stored.
The minimal command and arguments used to run 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-
)
The destination directory.
The location in the
Build Directory
where components are installed by the
do_install
task.
This location defaults to:
${WORKDIR}/image
The date the build was started. Dates appear using the year, month, and day (YMD) format (e.g. "20150209" for February 9th, 2015).
The date and time on which the current build started. The format is suitable for timestamps.
When the
debian
class is inherited, which is the default behavior,
DEBIAN_NOAUTONAME
specifies a
particular package should not be renamed according to
Debian library package naming.
You must use the package name as an override when you
set this variable.
Here is an example from the fontconfig
recipe:
DEBIAN_NOAUTONAME_fontconfig-utils = "1"
When the
debian
class is inherited, which is the default behavior,
DEBIANNAME
allows you to override the
library name for an individual package.
Overriding the library name in these cases is rare.
You must use the package name as an override when you
set this variable.
Here is an example from the dbus
recipe:
DEBIANNAME_${PN} = "dbus-1"
Specifies to build packages with debugging information.
This influences the value of the
SELECTED_OPTIMIZATION
variable.
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".
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.
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.
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
.
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.
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 in the Yocto Project Overview and
Concepts Manual, 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.
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 ${TMPDIR}/deploy
.
For more information on the structure of the Build
Directory, see
"The Build Directory - build/
"
section.
For more detail on the contents of the
deploy
directory, see the
"Images",
"Package Feeds",
and
"Application Development SDK"
sections all in the Yocto Project Overview and Concepts
Manual.
Points to the area that the OpenEmbedded build system uses
to place Debian packages that are ready to be used outside
of the build system.
This variable applies only when
PACKAGE_CLASSES
contains "package_deb".
The BitBake configuration file initially defines the
DEPLOY_DIR_DEB
variable as a
sub-folder of
DEPLOY_DIR
:
DEPLOY_DIR_DEB = "${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 in the Yocto Project Overview and Concepts Manual.
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 both in the Yocto Project Overview and Concepts
Manual.
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 = "${DEPLOY_DIR}/ipk"
The
package_ipk
class uses the
DEPLOY_DIR_IPK
variable to make sure
the
do_package_write_ipk
task writes IPK packages into the appropriate folder.
For more information on how packaging works, see the
"Package Feeds"
section in the Yocto Project Overview and Concepts Manual.
Points to the area that the OpenEmbedded build system uses
to place RPM packages that are ready to be used outside
of the build system.
This variable applies only when
PACKAGE_CLASSES
contains "package_rpm".
The BitBake configuration file initially defines this
variable as a sub-folder of
DEPLOY_DIR
:
DEPLOY_DIR_RPM = "${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 in the Yocto Project Overview and Concepts Manual.
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 = "${DEPLOY_DIR}/tar"
The
package_tar
class uses the
DEPLOY_DIR_TAR
variable to make sure
the
do_package_write_tar
task writes TAR packages into the appropriate folder.
For more information on how packaging works, see the
"Package Feeds"
section in the Yocto Project Overview and Concepts Manual.
When inheriting the
deploy
class, the DEPLOYDIR
points to a
temporary work area for deployed files that is set in the
deploy
class as follows:
DEPLOYDIR = "${WORKDIR}/deploy-${PN
}"
Recipes inheriting the deploy
class
should copy files to be deployed into
DEPLOYDIR
, and the class will take
care of copying them into
DEPLOY_DIR_IMAGE
afterwards.
The package description used by package managers.
If not set, DESCRIPTION
takes
the value of the
SUMMARY
variable.
A 32-bit MBR disk signature used by
directdisk
images.
By default, the signature is set to an automatically
generated random value that allows the OpenEmbedded
build system to create a boot loader.
You can override the signature in the image recipe
by setting DISK_SIGNATURE
to an
8-digit hex string.
You might want to override
DISK_SIGNATURE
if you want the disk
signature to remain constant between image builds.
When using Linux 3.8 or later, you can use
DISK_SIGNATURE
to specify the root
by UUID to allow the kernel to locate the root device
even if the device name changes due to differences in
hardware configuration.
By default, ROOT_VM
is set
as follows:
ROOT_VM ?= "root=/dev/sda2"
However, you can change this to locate the root device using the disk signature instead:
ROOT_VM = "root=PARTUUID=${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.
The short name of the distribution.
For information on the long name of the distribution, see
the
DISTRO_NAME
variable.
The DISTRO
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.
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.
Specifies a codename for the distribution being built.
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.
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.
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.
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.
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.
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"
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.
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.
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.
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.
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.
The long name of the distribution.
For information on the short name of the distribution, see
the
DISTRO
variable.
The DISTRO_NAME
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_NAME
variable is set as
follows:
DISTRO_NAME = "Poky (Yocto Project Reference Distro)"
Distribution configuration files are located in a
conf/distro
directory within the
Metadata
that contains the distribution configuration.
DISTRO_NAME
variable is
blank, a set of default configurations are used, which
are specified within
meta/conf/distro/defaultsetup.conf
also in the Source Directory.
The version of the 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
.
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.
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.
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.
When building bootable images (i.e. where
hddimg
, iso
,
or wic.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.
Variable that controls which locales for
glibc
are generated during the
build (useful if the target device has 64Mbytes
of RAM or less).
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
"
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.
Triggers the OpenEmbedded build system's shared libraries resolver to exclude an entire package when scanning for shared libraries.
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"
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.
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.
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.
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.
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.
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 Tasks Manual.
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 Tasks Manual.
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".
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.
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 Tasks 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 Tasks Manual.
Specifies additional options for the image
creation command that has been specified in
IMAGE_CMD
.
When setting this variable, use an override for the
associated image type.
Here is an example:
EXTRA_IMAGECMD_ext3 ?= "-i 4096"
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.
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"
Additional
CMake
options.
See the
cmake
class for additional information.
Additional configure
script options.
See
PACKAGECONFIG_CONFARGS
for additional information on passing configure script
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.
When inheriting the
scons
class, this variable specifies additional configuration
options you want to pass to the
scons
command line.
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; \ # "
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.
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.
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.
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 files or paths, you can pattern
match using Python's
glob
syntax.
For details on the syntax, see the
documentation by following the previous link.
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
${bindir}
rather than
/usr/bin
.
You can find a list of these variables at the
top of the
meta/conf/bitbake.conf
file in the
Source Directory.
You will also find the default values of the
various FILES_*
variables
in this file.
If some of the files you provide with the
FILES
variable are editable and you
know they should not be overwritten during the package
update process by the Package Management System (PMS), you
can identify these files so that the PMS will not
overwrite them.
See the
CONFFILES
variable for information on how to identify these files to
the PMS.
Defines the file specification to match
SOLIBSDEV
.
In other words, FILES_SOLIBSDEV
defines the full path name of the development symbolic link
(symlink) for shared libraries on the target platform.
The following statement from the
bitbake.conf
shows how it is set:
FILES_SOLIBSDEV ?= "${base_libdir}/lib*${SOLIBSDEV} ${libdir}/lib*${SOLIBSDEV}"
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 := "${THISDIR}/files:"
In this example, the build system extends the
FILESPATH
variable to include a
directory named files
that is in the
same directory as the corresponding append file.
This next example specifically adds three paths:
FILESEXTRAPATHS_prepend := "path_1:path_2:path_3:"
A final example shows how you can extend the search path
and include a
MACHINE
-specific
override, which is useful in a BSP layer:
FILESEXTRAPATHS_prepend_intel-x86-common := "${THISDIR}/${PN}:"
The previous statement appears in the
linux-yocto-dev.bbappend
file, which
is found in the Yocto Project
Source Repositories
in
meta-intel/common/recipes-kernel/linux
.
Here, the machine override is a special
PACKAGE_ARCH
definition for multiple meta-intel
machines.
MACHINE
.
By prepending paths in .bbappend
files, you allow multiple append files that reside in
different layers but are used for the same recipe to
correctly extend the path.
A subset of OVERRIDES
used by the OpenEmbedded build system for creating
FILESPATH
.
You can find more information on how overrides are handled
in the
BitBake User Manual.
By default, the FILESOVERRIDES
variable is defined as:
FILESOVERRIDES = "${TRANSLATED_TARGET_ARCH}:${MACHINEOVERRIDES}:${DISTROOVERRIDES}"
FILESOVERRIDES
variable.
The values match up with expected overrides and are
used in an expected manner by the build system.
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's
SRC_URI
statements.
You can take advantage of this searching behavior in useful ways. For example, consider a case where the following directory structure exists for general and machine-specific configurations:
files/defconfig files/MACHINEA/defconfig files/MACHINEB/defconfig
Also in the example, the SRC_URI
statement contains "file://defconfig".
Given this scenario, you can set
MACHINE
to "MACHINEA" and cause the build system to use files
from files/MACHINEA
.
Set MACHINE
to "MACHINEB" and the
build system uses files from
files/MACHINEB
.
Finally, for any machine other than "MACHINEA" and
"MACHINEB", the build system uses files from
files/defconfig
.
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)}"
The FILESPATH
variable is automatically
extended using the overrides from the
FILESOVERRIDES
variable.
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.
You can find out more about the patching process in the
"Patching"
section in the Yocto Project Overview and Concepts Manual
and the
"Patching Code"
section in the Yocto Project Development Tasks Manual.
See the
do_patch
task as well.
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
.
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".
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.
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.
The options to pass in
TARGET_CFLAGS
and CFLAGS
when compiling an optimized system.
This variable defaults to
"-O2 -pipe ${DEBUG_FLAGS}".
Enables Position Independent Executables (PIE) within the GNU C Compiler (GCC). Enabling PIE in the GCC makes Return Oriented Programming (ROP) attacks much more difficult to execute.
By default the security_flags.inc
file enables PIE by setting the variable as follows:
GCCPIE ?= "--enable-default-pie"
Specifies the default version of the GNU C Compiler (GCC)
used for compilation.
By default, GCCVERSION
is set to
"8.x" in the
meta/conf/distro/include/tcmode-default.inc
include file:
GCCVERSION ?= "8.%"
You can override this value by setting it in a configuration
file such as the local.conf
.
The minimal command and arguments to run the GNU Debugger.
The directory in which a local copy of a Git repository is stored when it is cloned.
Specifies the list of GLIBC locales to generate should you not wish to generate all LIBC locals, which can be time consuming.
You can set GLIBC_GENERATE_LOCALES
in your local.conf
file.
By default, all locales are generated.
GLIBC_GENERATE_LOCALES = "en_GB.UTF-8 en_US.UTF-8"
When inheriting the
useradd
class, this variable
specifies for a package what parameters should be passed
to the groupadd
command
if you wish to add a group to the system when the package
is installed.
Here is an example from the dbus
recipe:
GROUPADD_PARAM_${PN} = "-r netdev"
For information on the standard Linux shell command
groupadd
, see
http://linux.die.net/man/8/groupadd.
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
http://linux.die.net/man/8/groupmems.
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.
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.
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.
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.
Website where more information about the software the recipe is building can be found.
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
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-
)
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-musl" for musl
.
For ARM/EABI targets, there are also "linux-gnueabi" and
"linux-musleabi" values possible.
Specifies the prefix for the cross-compile toolchain.
HOST_PREFIX
is normally the same as
TARGET_PREFIX
.
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.
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".
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
.
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 an 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.
Specifies the name of the vendor.
HOST_VENDOR
is normally the same as
TARGET_VENDOR
.
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 = ""
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
.
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.
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
).
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
.
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.
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.
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.
The base name of image output files.
This variable defaults to the recipe name
(${
PN
}
).
A space-separated list of files installed into the
boot partition when preparing an image using the Wic tool
with the bootimg-partition
source
plugin.
By default, the files are installed under the same name as
the source files.
To change the installed name, separate it from the
original name with a semi-colon (;).
Source files need to be located in
DEPLOY_DIR_IMAGE
.
Here are two examples:
IMAGE_BOOT_FILES = "u-boot.img uImage;kernel" IMAGE_BOOT_FILES = "u-boot.${UBOOT_SUFFIX} ${KERNEL_IMAGETYPE}"
Alternatively, source files can be picked up using a glob pattern. In this case, the destination file must 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
${DEPLOY_DIR_IMAGE}/bcm2835-bootfiles
into the root of the target partition.
The second example installs the same files into a
boot
directory within the
target partition.
You can find information on how to use the Wic tool in the "Creating Partitioned Images Using Wic" section of the Yocto Project Development Tasks Manual. Reference material for Wic is located in the "OpenEmbedded Kickstart (.wks) Reference" chapter.
A list of classes that all images should inherit. You typically use this variable to specify the list of classes that register the different types of images the OpenEmbedded build system creates.
The default value for IMAGE_CLASSES
is
image_types
.
You can set this variable in your
local.conf
or in a distribution
configuration file.
For more information, see
meta/classes/image_types.bbclass
in the
Source Directory.
Specifies the command to create the image file for a
specific image type, which corresponds to the value set
set in
IMAGE_FSTYPES
,
(e.g. ext3
,
btrfs
, and so forth).
When setting this variable, you should use
an override for the associated type.
Here is an example:
IMAGE_CMD_jffs2 = "mkfs.jffs2 --root=${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
.
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.
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.
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 Tasks Manual.
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 an image recipe uses the "inherit image" line
and you are setting
IMAGE_FSTYPES
inside the
recipe, you must set
IMAGE_FSTYPES
prior to
using the "inherit image" line.
Due to the way the OpenEmbedded build system
processes this variable, you cannot update its
contents by using _append
or
_prepend
.
You must use the +=
operator to add one or more options to the
IMAGE_FSTYPES
variable.
Used by recipes to specify the packages to install into an
image through the
image
class.
Use the IMAGE_INSTALL
variable with
care to avoid ordering issues.
Image recipes set IMAGE_INSTALL
to specify the packages to install into an image through
image.bbclass
.
Additionally, "helper" classes such as the
core-image
class exist that can take lists used with
IMAGE_FEATURES
and turn them into auto-generated entries in
IMAGE_INSTALL
in addition to its
default contents.
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.
When working with a
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 Tasks
Manual.
Using IMAGE_INSTALL
with
the
+=
BitBake operator within the
/conf/local.conf
file or
from within an image recipe is not recommended.
Use of this operator in these ways can cause
ordering issues.
Since core-image.bbclass
sets IMAGE_INSTALL
to a
default value using the
?=
operator, using a +=
operation against
IMAGE_INSTALL
results in
unexpected behavior when used within
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.
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.
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}/${IMAGE_NAME}.rootfs.manifest"
The location is derived using the
DEPLOY_DIR_IMAGE
and
IMAGE_NAME
variables.
You can find information on how the image
is created in the
"Image Generation"
section in the Yocto Project Overview and Concepts Manual.
The name of the output image files minus the extension.
This variable is derived using the
IMAGE_BASENAME
,
MACHINE
,
and
DATETIME
variables:
IMAGE_NAME = "${IMAGE_BASENAME}-${MACHINE}-${DATETIME}"
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.
Defines the package type (i.e. 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.
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
.tar
format are
never used as a substitute packaging format for DEB,
RPM, and IPK formatted files for your image or SDK.
Specifies a list of functions to call once the OpenEmbedded build system creates 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.
Specifies a list of functions to call before the OpenEmbedded build system creates 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.
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.
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.
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"
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.
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.
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 squashfs squashfs-lzo squashfs-xz tar tar.bz2 tar.gz tar.lz4 tar.xz ubi ubifs 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.
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.
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.
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.
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 Bitbake User Manual.
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"
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.
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"
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.
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.
Specifies the
PROVIDES
name of an image recipe that is used to build an initial
RAM filesystem (initramfs) image.
In other words, the INITRAMFS_IMAGE
variable causes an additional recipe to be built as
a dependency to whatever root filesystem recipe you
might be using (e.g. core-image-sato
).
The initramfs image recipe you provide should set
IMAGE_FSTYPES
to
INITRAMFS_FSTYPES
.
An initramfs image provides a temporary root filesystem used for early system initialization (e.g. loading of modules needed to locate and mount the "real" root filesystem).
meta/recipes-core/images/core-image-minimal-initramfs.bb
recipe in the
Source Directory
for an example initramfs recipe.
To select this sample recipe as the one built
to provide the initramfs image,
set INITRAMFS_IMAGE
to
"core-image-minimal-initramfs".
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 image 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
image, see the
"Building an Initial RAM Filesystem (initramfs) Image"
section in the Yocto Project Development Tasks Manual.
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.
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 ?= ""
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 Tasks Manual.
The link name of the initial RAM filesystem image.
This variable is set in the
meta/classes/kernel-artifact-names.bbclass
file as follows:
INITRAMFS_LINK_NAME ?= "initramfs-${KERNEL_ARTIFACT_LINK_NAME}"
The value of the KERNEL_ARTIFACT_LINK_NAME
variable, which is set in the same file, has the following
value:
KERNEL_ARTIFACT_LINK_NAME ?= "${MACHINE}"
See the
MACHINE
variable for additional information.
The base name of the initial RAM filesystem image.
This variable is set in the
meta/classes/kernel-artifact-names.bbclass
file as follows:
INITRAMFS_NAME ?= "initramfs-${KERNEL_ARTIFACT_NAME}"
The value of the
KERNEL_ARTIFACT_NAME
variable, which is set in the same file, has the following
value:
KERNEL_ARTIFACT_NAME ?= "${PKGE}-${PKGV}-${PKGR}-${MACHINE}${IMAGE_VERSION_SUFFIX}"
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.
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.
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.
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.
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
http://www.tin.org/bin/man.cgi?section=8&topic=update-rc.d.
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.
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.
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.
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.
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
linux-yocto_4.12
kernel, the kernel
recipe file is the
meta/recipes-kernel/linux/linux-yocto_4.12.bb
file.
KBRANCH
is set as follows in that
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.
Continuing with the previous kernel example, the kernel's
append file (i.e.
linux-yocto_4.12.bbappend
) is located
in the BSP layer for a given machine.
For example, the append file for the Beaglebone,
EdgeRouter, and generic versions of both 32 and 64-bit IA
machines (meta-yocto-bsp
) is named
meta-yocto-bsp/recipes-kernel/linux/linux-yocto_4.12.bbappend
.
Here are the related statements from that append file:
KBRANCH_genericx86 = "standard/base" KBRANCH_genericx86-64 = "standard/base" KBRANCH_edgerouter = "standard/edgerouter" KBRANCH_beaglebone = "standard/beaglebone" KBRANCH_mpc8315e-rdb = "standard/fsl-mpc8315e-rdb"
The KBRANCH
statements identify
the kernel branch to use when building for each
supported BSP.
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
place 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 and append
the
KMACHINE
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 in the Yocto Project Linux Kernel Development
Manual.
Specifies an alternate kernel image type for creation in
addition to the kernel image type specified using the
KERNEL_IMAGETYPE
variable.
Specifies the name of all of the build artifacts.
You can change the name of the artifacts by changing the
KERNEL_ARTIFACT_NAME
variable.
The value of KERNEL_ARTIFACT_NAME
,
which is set in the
meta/classes/kernel-artifact-names.bbclass
file, has the following default value:
KERNEL_ARTIFACT_NAME ?= "${PKGE}-${PKGV}-${PKGR}-${MACHINE}${IMAGE_VERSION_SUFFIX}"
See the
PKGE
,
PKGV
,
PKGR
,
and
MACHINE
variables for additional information.
A list of classes defining kernel image types that the
kernel
class should inherit.
You typically append this variable to enable extended image
types.
An example is the "kernel-fitimage", which enables
fitImage support and resides in
meta/classes/kernel-fitimage.bbclass
.
You can register custom kernel image types with the
kernel
class using this variable.
Specifies the name of the generated Linux kernel device tree
(i.e. the .dtb
) file.
.dtb
file is preferred.
In order to use this variable, you must have the include files in your kernel recipe:
require recipes-kernel/linux/linux-dtb.inc
or
require recipes-kernel/linux/linux-yocto.inc
The link name of the kernel device tree binary (DTB).
This variable is set in the
meta/classes/kernel-artifact-names.bbclass
file as follows:
KERNEL_DTB_LINK_NAME ?= "${KERNEL_ARTIFACT_LINK_NAME}"
The value of the KERNEL_ARTIFACT_LINK_NAME
variable, which is set in the same file, has the following
value:
KERNEL_ARTIFACT_LINK_NAME ?= "${MACHINE}"
See the
MACHINE
variable for additional information.
The base name of the kernel device tree binary (DTB).
This variable is set in the
meta/classes/kernel-artifact-names.bbclass
file as follows:
KERNEL_DTB_NAME ?= "${KERNEL_ARTIFACT_NAME}"
The value of the
KERNEL_ARTIFACT_NAME
variable, which is set in the same file, has the following
value:
KERNEL_ARTIFACT_NAME ?= "${PKGE}-${PKGV}-${PKGR}-${MACHINE}${IMAGE_VERSION_SUFFIX}"
Specifies additional make
command-line arguments the OpenEmbedded build system
passes on when compiling the kernel.
Includes additional kernel metadata.
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 from within the kernel recipe or kernel append
file to further add metadata for all BSPs or specific
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 example from the
linux-yocto-rt_4.12
kernel recipe
adds "netfilter" and "taskstats" features to all BSPs
as well as "virtio" configurations to all QEMU machines.
The last two statements add specific configurations to
targeted machine types:
KERNEL_EXTRA_FEATURES ?= "features/netfilter/netfilter.scc features/taskstats/taskstats.scc" KERNEL_FEATURES_append = " ${KERNEL_EXTRA_FEATURES}" KERNEL_FEATURES_append_qemuall = " cfg/virtio.scc" KERNEL_FEATURES_append_qemux86 = " cfg/sound.scc cfg/paravirt_kvm.scc" KERNEL_FEATURES_append_qemux86-64 = " cfg/sound.scc"
The link name of the kernel flattened image tree (FIT) image.
This variable is set in the
meta/classes/kernel-artifact-names.bbclass
file as follows:
KERNEL_FIT_LINK_NAME ?= "${KERNEL_ARTIFACT_LINK_NAME}"
The value of the KERNEL_ARTIFACT_LINK_NAME
variable, which is set in the same file, has the following
value:
KERNEL_ARTIFACT_LINK_NAME ?= "${MACHINE}"
See the
MACHINE
variable for additional information.
The base name of the kernel flattened image tree (FIT) image.
This variable is set in the
meta/classes/kernel-artifact-names.bbclass
file as follows:
KERNEL_FIT_NAME ?= "${KERNEL_ARTIFACT_NAME}"
The value of the
KERNEL_ARTIFACT_NAME
variable, which is set in the same file, has the following
value:
KERNEL_ARTIFACT_NAME ?= "${PKGE}-${PKGV}-${PKGR}-${MACHINE}${IMAGE_VERSION_SUFFIX}"
The link name for the kernel image.
This variable is set in the
meta/classes/kernel-artifact-names.bbclass
file as follows:
KERNEL_IMAGE_LINK_NAME ?= "${KERNEL_ARTIFACT_LINK_NAME}"
The value of the KERNEL_ARTIFACT_LINK_NAME
variable, which is set in the same file, has the following
value:
KERNEL_ARTIFACT_LINK_NAME ?= "${MACHINE}"
See the
MACHINE
variable for additional information.
Specifies the maximum size of the kernel image file in
kilobytes.
If KERNEL_IMAGE_MAXSIZE
is set,
the size of the kernel image file is checked against
the set value during the
do_sizecheck
task.
The task fails if the kernel image file is larger than
the setting.
KERNEL_IMAGE_MAXSIZE
is useful for
target devices that have a limited amount of space in
which the kernel image must be stored.
By default, this variable is not set, which means the size of the kernel image is not checked.
The base name of the kernel image.
This variable is set in the
meta/classes/kernel-artifact-names.bbclass
file as follows:
KERNEL_IMAGE_NAME ?= "${KERNEL_ARTIFACT_NAME}"
The value of the
KERNEL_ARTIFACT_NAME
variable, which is set in the same file, has the following
value:
KERNEL_ARTIFACT_NAME ?= "${PKGE}-${PKGV}-${PKGR}-${MACHINE}${IMAGE_VERSION_SUFFIX}"
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.
Lists kernel modules that need to be auto-loaded during boot.
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.
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.
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 in the Yocto Project Linux Kernel Development
Manual.
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.
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 in the Yocto Project Linux Kernel Development
Manual.
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.
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.
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.
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"
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".
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.
Provides a list of targets for automatic configuration.
See the
grub-efi
class for more information on how this variable is used.
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
).
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.
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
.
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
).
Lists the versions of the
OpenEmbedded-Core for which
a layer is compatible.
Using the LAYERSERIES_COMPAT
variable
allows the layer maintainer to indicate which combinations
of the layer and OE-Core can be expected to work.
The variable gives the system a way to detect when a layer
has not been tested with new releases of OE-Core (e.g.
the layer is not maintained).
To specify the OE-Core versions for which a layer is
compatible, use this variable in your layer's
conf/layer.conf
configuration file.
For the list, use the Yocto Project
Release Name
(e.g. warrior).
To specify multiple OE-Core versions for the layer,
use a space-separated list:
LAYERSERIES_COMPAT_layer_root_name
= "warrior thud"
LAYERSERIES_COMPAT
is
required by the Yocto Project Compatible version 2
standard.
The OpenEmbedded build system produces a warning if
the variable is not set for any given layer.
See the "Creating Your Own Layer" section in the Yocto Project Development Tasks Manual.
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
).
The minimal command and arguments used to run 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-
)
Specifies the lead (or primary) compiled library file
(i.e. .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.
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 in the Yocto Project Development Tasks Manual.
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"
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 Tasks Manual.
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 in the Yocto Project Development Tasks Manual.
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 in the Yocto Project Development Tasks Manual.
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
"
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.
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${SRCPV}"
A string extension compiled into the version string of the Linux kernel built with the OpenEmbedded build system. You define this variable in the kernel recipe. For example, the linux-yocto kernel recipes all define the variable as follows:
LINUX_VERSION_EXTENSION ?= "-yocto-${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
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.
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.
MACHINE
.
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.
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"
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"
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).
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"
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"
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.
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.
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.
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
.
The email address of the distribution maintainer.
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.
Specifies a prefix has been added to
PN
to create a special version
of a recipe or package (i.e. 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
.
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"
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.
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.
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.
The link name of the kernel module tarball.
This variable is set in the
meta/classes/kernel-artifact-names.bbclass
file as follows:
MODULE_TARBALL_LINK_NAME ?= "${KERNEL_ARTIFACT_LINK_NAME}"
The value of the KERNEL_ARTIFACT_LINK_NAME
variable, which is set in the same file, has the following
value:
KERNEL_ARTIFACT_LINK_NAME ?= "${MACHINE}"
See the
MACHINE
variable for additional information.
The base name of the kernel module tarball.
This variable is set in the
meta/classes/kernel-artifact-names.bbclass
file as follows:
MODULE_TARBALL_NAME ?= "${KERNEL_ARTIFACT_NAME}"
The value of the
KERNEL_ARTIFACT_NAME
variable, which is set in the same file, has the following
value:
KERNEL_ARTIFACT_NAME ?= "${PKGE}-${PKGV}-${PKGR}-${MACHINE}${IMAGE_VERSION_SUFFIX}"
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.
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.
The minimal command and arguments to run
nm
.
Avoids QA errors when you use a non-common, non-CLOSED
license in a recipe.
Packages exist, such as the linux-firmware package, with
many licenses that are not in any way common.
Also, new licenses are added occasionally to avoid
introducing a lot of common license files, which are only
applicable to a specific package.
NO_GENERIC_LICENSE
is used to allow
copying a license that does not exist in common licenses.
The following example shows how to add
NO_GENERIC_LICENSE
to a recipe:
NO_GENERIC_LICENSE[license_name
] = "license_file_in_fetched_source
"
The following is an example that uses the
LICENSE.Abilis.txt
file as the license
from the fetched source:
NO_GENERIC_LICENSE[Firmware-Abilis] = "LICENSE.Abilis.txt"
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.
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.
Disables auto package from splitting
.debug
files. If a recipe requires
FILES_${PN}-dbg
to be set manually,
the NOAUTOPACKAGEDEBUG
can be defined
allowing you to define the content of the debug package.
For example:
NOAUTOPACKAGEDEBUG = "1" FILES_${PN}-dev = "${includedir}/${QT_DIR_NAME}/Qt/*" FILES_${PN}-dbg = "/usr/src/debug/" FILES_${QT_BASE_NAME}-demos-doc = "${docdir}/${QT_DIR_NAME}/qch/qt.qch"
The minimal command and arguments to run
objcopy
.
The minimal command and arguments to run
objdump
.
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
class, see the
"binconfig.bbclass
"
section.
An internal variable used to tell the OpenEmbedded build system what Python modules to import for every Python function run by the system.
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.
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 Tasks Manual.
You can use the following values for the
OE_TERMINAL
variable:
auto gnome xfce rxvt screen konsole none
The directory from which the top-level build environment
setup script is sourced.
The Yocto Project provides a top-level build environment
setup script:
oe-init-build-env
.
When you run this script, the
OEROOT
variable resolves to the
directory that contains the script.
For additional information on how this variable is used, see the initialization script.
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.
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"
OVERRIDES
in the output of the
bitbake -e
command.
See the
"Viewing Variable Values"
section in the Yocto Project Development Tasks
Manual for more information.
The recipe name and version.
P
is comprised of the following:
${PN}-${PV}
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.
SDK_ARCH
for more information.
However, if your recipe's output packages are built
specific to the target machine rather than generally 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}"
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}".
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.
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"
package_tar
class has limited
functionality due to no support for package
dependencies by that backend.
Therefore, 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.
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
.
"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.
"debug-with-srcpkg": The same behavior as
".debug" previously described with the exception
that all source files are placed in a separate
*-src
pkg.
This is the default behavior.
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 Tasks Manual.
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.
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.
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.
Optionally specifies the package architectures used as
part of the package feed URIs during the build.
When used, 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.
PACKAGE_FEEDS_ARCHS
variable to whitelist specific package architectures.
If you do not need to whitelist specific architectures,
which is a common case, you can omit this variable.
Omitting the variable results in all available
architectures for the current machine being included
into remote package feeds.
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
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
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
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.
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 Tasks Manual.
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.
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 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_DEPS
.
For information on running post-installation scripts, see the "Post-Installation Scripts" section in the Yocto Project Development Tasks Manual.
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,rt-recs-f1" PACKAGECONFIG[f2] = "--with-f2,--without-f2,build-deps-f2,rt-deps-f2,rt-recs-f2" PACKAGECONFIG[f3] = "--with-f3,--without-f3,build-deps-f3,rt-deps-f3,rt-recs-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 five 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.
Additional runtime recommendations
(RRECOMMENDS
)
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
file.
As with append files previously described,
you can either completely override the variable:
mydistro
.conf
PACKAGECONFIG_pn-recipename
= "f4 f5"
Or, you can just amend the variable:
PACKAGECONFIG_append_pn-recipename
= " f4"
A space-separated list of configuration options generated
from the
PACKAGECONFIG
setting.
Classes such as
autotools
and
cmake
use PACKAGECONFIG_CONFARGS
to pass
PACKAGECONFIG
options to
configure
and
cmake
, respectively.
If you are using
PACKAGECONFIG
but not a class that
handles the do_configure
task, then
you need to use
PACKAGECONFIG_CONFARGS
appropriately.
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.
The list of packages the recipe creates. 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.
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 Tasks Manual.
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.
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.
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.
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 Tasks 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 a Build" section in the Yocto Project Development Tasks Manual.
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 Tasks Manual.
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.
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"
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.
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}
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.
The name of the resulting package created by the OpenEmbedded build system.
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
The path to pkg-config
files for the
current build context.
pkg-config
reads this variable
from the environment.
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.
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 in the Yocto Project Overview and Concepts Manual
and the
"Viewing Package Information with oe-pkgdata-util
"
section in the Yocto Project Development Tasks Manual.
For more information on the shared, global-state directory,
see
STAGING_DIR_HOST
.
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.
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.
The epoch of the package(s) built by the recipe.
By default, PKGE
is set to
PE
.
The revision of the package(s) built by the recipe.
By default, PKGR
is set to
PR
.
The version of the package(s) built by the
recipe.
By default, PKGV
is set to
PV
.
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.
Lists recipes you do not want the OpenEmbedded build system
to build.
This variable works in conjunction with the
blacklist
class, which is inherited globally.
To prevent a recipe from being built, use the
PNBLACKLIST
variable in your
local.conf
file.
Here is an example that prevents
myrecipe
from being built:
PNBLACKLIST[myrecipe] = "Not supported by our organization."
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.
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.
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".
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 in the Yocto Project Development Tasks Manual
for more information.
If multiple recipes provide the same item, this variable
determines which recipe is preferred and thus provides
the item (i.e. the preferred provider).
You should always suffix this variable with the name of the
provided item.
And, you should define the variable using the preferred
recipe's name
(PN
).
Here is a common example:
PREFERRED_PROVIDER_virtual/kernel ?= "linux-yocto"
In the previous example, multiple recipes are providing
"virtual/kernel".
The PREFERRED_PROVIDER
variable is
set with the name (PN
) of the recipe
you prefer to provide "virtual/kernel".
Following are more examples:
PREFERRED_PROVIDER_virtual/xserver = "xserver-xf86" PREFERRED_PROVIDER_virtual/libgl ?= "mesa"
For more information, see the "Using Virtual Providers" section in the Yocto Project Development Tasks Manual.
virtual/*
item
with PREFERRED_PROVIDER
, then any
recipe that
PROVIDES
that item but is not selected (defined) by
PREFERRED_PROVIDER
is prevented
from building, which is usually desirable since this
mechanism is designed to select between mutually
exclusive alternative providers.
If multiple versions of recipes exist, this
variable determines which version is given preference.
You must always suffix the variable with the
PN
you want to select, and you should set the
PV
accordingly for precedence.
The PREFERRED_VERSION
variable
supports limited wildcard use through the
"%
" character.
You can use the character to match any number of
characters, which can be useful when specifying versions
that contain long revision numbers that potentially change.
Here are two examples:
PREFERRED_VERSION_python = "3.4.0" PREFERRED_VERSION_linux-yocto = "4.12%"
%
" character
is limited in that it only works at the end of the
string.
You cannot use the wildcard character in any other
location of the string.
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 = "4.12%"
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 = "4.12%"
_forcevariable
override is
not handled specially.
This override only works because the default value of
OVERRIDES
includes
"forcevariable".
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.
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.
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 in the Yocto Project Overview and Concepts Manual.
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"
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.
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
.
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.
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.
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 += "${PYTHON_PN}-native"
In the previous example, the version of the dependency
is PYTHON_PN
.
The minimal command and arguments to run
ranlib
.
The list of packages that conflict with packages. Note that packages will not be installed if conflicting packages are not first removed.
Like all package-controlling variables, you must always use them in conjunction with a package name override. Here is an example:
RCONFLICTS_${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)"
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 in the Yocto Project Overview and Concepts Manual.
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_${PN} = "package
(operator
version
)"
For operator
, you can specify the
following:
= < > <= >=
For version
, provide the version
number.
EXTENDPKGV
to provide a full package version specification.
For example, the following sets up a dependency on version
1.2 or greater of the package foo
:
RDEPENDS_${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.
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.
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.
Defines the root home directory. By default, this directory is set as follows in the BitBake configuration file:
ROOT_HOME ??= "/home/root"
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.
Indicates a filesystem image to include as the root filesystem.
The ROOTFS
variable is an optional
variable used with the
image-live
class.
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.
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.
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.
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
${IMAGE_ROOTFS}
, which points to
the directory that becomes the root filesystem image.
See the
IMAGE_ROOTFS
variable for more information.
A list of package name aliases that a package also provides.
These aliases are useful for satisfying runtime dependencies
of other packages both during the build and on the target
(as specified by
RDEPENDS
).
RPROVIDES
list.
As with all package-controlling variables, you must always use the variable in conjunction with a package name override. Here is an example:
RPROVIDES_${PN} = "widget-abi-2"
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)"
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_${PN} = "foo (>= 1.2)"
A list of additional packages that you can suggest for installation by the package manager at the time a package is installed. Not all package managers support this functionality.
As with all package-controlling variables, you must always use this variable in conjunction with a package name override. Here is an example:
RSUGGESTS_${PN} = "useful_package
another_package
"
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 is 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"
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.
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.
The target architecture for the SDK.
Typically, you do not directly set this variable.
Instead, use
SDKMACHINE
.
The directory set up and used by the
populate_sdk_base
class to which the SDK is deployed.
The populate_sdk_base
class defines
SDK_DEPLOY
as follows:
SDK_DEPLOY = "${TMPDIR}/deploy/sdk"
The parent directory used by the OpenEmbedded build system
when creating SDK output.
The
populate_sdk_base
class defines the variable as follows:
SDK_DIR = "${WORKDIR}/sdk"
SDK_DIR
directory is a
temporary directory as it is part of
WORKDIR
.
The final output directory is
SDK_DEPLOY
.
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.
SSTATE_MIRRORS
is set in the SDK's configuration to enable the
artifacts to be fetched as needed.
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 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.
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.
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.
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".
A list of classes to remove from the
INHERIT
value globally within the extensible SDK configuration.
The
populate-sdk-ext
class sets the default value:
SDK_INHERIT_BLACKLIST ?= "buildhistory icecc"
Some classes are not generally applicable within the extensible SDK context. You can use this variable to disable those classes.
For additional information on how to customize the extensible SDK's configuration, see the "Configuring the Extensible SDK" section in the Yocto Project Application Development and the Extensible Software Development Kit (eSDK) manual.
A list of variables not allowed through from the OpenEmbedded 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.
By default,
SDK_LOCAL_CONF_BLACKLIST
is set in the
populate-sdk-ext
class and excludes the following variables:
CONF_VERSION BB_NUMBER_THREADS BB_NUMBER_PARSE_THREADS PARALLEL_MAKE PRSERV_HOST SSTATE_MIRRORS DL_DIR SSTATE_DIR TMPDIR BB_SERVER_TIMEOUT
For additional information on how to customize the extensible SDK's configuration, see the "Configuring the Extensible SDK" section in the Yocto Project Application Development and the Extensible Software Development Kit (eSDK) manual.
A list of variables allowed through from the OpenEmbedded
build system configuration into the extensible SDK
configuration.
By default, the list of variables is empty and is set in
the
populate-sdk-ext
class.
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.
For additional information on how to customize the extensible SDK's configuration, see the "Configuring the Extensible SDK" section in the Yocto Project Application Development and the Extensible Software Development Kit (eSDK) manual.
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}-${TUNE_PKGARCH}"
Specifies the operating system for which the SDK
will be built.
The default value is the value of
BUILD_OS
.
The location used by the OpenEmbedded build system when
creating SDK output.
The
populate_sdk_base
class defines the variable as follows:
SDK_DIR = "${WORKDIR}/sdk" SDK_OUTPUT = "${SDK_DIR}/image" SDK_DEPLOY = "${DEPLOY_DIR}/sdk"
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
.
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}".
Specifies a list of functions to call once the OpenEmbedded build system creates 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
${SDK_DIR}
, which points to
the parent directory used by the OpenEmbedded build system
when creating SDK output.
See the
SDK_DIR
variable for more information.
The toolchain binary prefix used for
nativesdk
recipes.
The OpenEmbedded build system uses the
SDK_PREFIX
value to set the
TARGET_PREFIX
when building nativesdk
recipes.
The default value is "${SDK_SYS}-".
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
).
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.
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.
A list of targets to install from shared state as part of the standard or extensible SDK installation. The default value is "${PN}" (i.e. the image from which the SDK is built).
The SDK_TARGETS
variable is an
internal variable and typically would not be changed.
The title to be printed when running the SDK installer.
By default, this title is based on the
DISTRO_NAME
or
DISTRO
variable and is set in the
populate_sdk_base
class as follows:
SDK_TITLE ??= "${@d.getVar('DISTRO_NAME') or d.getVar('DISTRO')} SDK"
For the default distribution "poky",
SDK_TITLE
is set to
"Poky (Yocto Project Reference Distro)".
For information on how to change this default title, see the "Changing the Extensible SDK Installer Title" section in the Yocto Project Application Development and the Extensible Software Development Kit (eSDK) manual.
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.
Specifies the name of the SDK vendor.
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 = "${@d.getVar('DISTRO_VERSION').replace('snapshot-${DATE}','snapshot')}"
For additional information, see the
DISTRO_VERSION
and
DATE
variables.
The default installation directory for the Extensible SDK.
By default, this directory is based on the
DISTRO
variable and is set in the
populate_sdk_base
class as follows:
SDKEXTPATH ??= "~/${@d.getVar('DISTRO')}_sdk"
For the default distribution "poky", the
SDKEXTPATH
is set to "poky_sdk".
For information on how to change this default directory, see the "Changing the Default SDK Installation Directory" section in the Yocto Project Application Development and the Extensible Software Development Kit (eSDK) manual.
Equivalent to
IMAGE_FEATURES
.
However, this variable applies to the SDK generated from an
image using the following command:
$ bitbake -c populate_sdk imagename
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"
SDKMACHINE
variable in your distribution configuration file.
If you do, the configuration will not take affect.
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.
The full path to the sysroot used for cross-compilation
within an SDK as it will be when installed into the
default
SDKPATH
.
The section in which packages should be categorized. Package management utilities can make use of this variable.
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.
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"
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 semicolon. Use spaces to separate multiple devices:
SERIAL_CONSOLES = "115200;ttyS0 115200;ttyS1"
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).
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 the previous example, intone
depends on mplayer2
.
You can use the special token "*"
on
the left-hand side of the dependency to match all
recipes except the one on the right-hand side.
Here is an example:
SIGGEN_EXCLUDE_SAFE_RECIPE_DEPS += "*->quilt-native"
In the previous example, all recipes except
quilt-native
ignore task
signatures from the quilt-native
recipe when determining their task signatures.
Use of this variable is one mechanism to remove dependencies that affect task signatures and thus force rebuilds when a recipe changes.
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.
Specifies the number of bits for the target system CPU. The value should be either "32" or "64".
Specifies the endian byte order of the target system. The value should be either "le" for little-endian or "be" for big-endian.
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"
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.
conf/machine/include/soc-family.inc
for this variable to appear in
MACHINEOVERRIDES
.
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_${PN}
.
Defines the suffix for the development symbolic link
(symlink) for shared libraries on the target platform.
By default, this suffix is ".so" for Linux-based
systems and is defined in the
meta/conf/bitbake.conf
configuration
file.
You will see this variable referenced in the default values
of FILES_${PN}-dev
.
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.
SOURCE_MIRROR_FETCH
variable
unless you are creating a source mirror.
In other words, do not set the variable during a
normal build.
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
"
SOURCE_MIRROR_URL
.
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.
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.
The file type for the Secondary Program Loader (SPL).
Some devices use an SPL from which to boot (e.g. the
BeagleBone development board).
For such cases, you can declare the file type of the
SPL binary in the u-boot.inc
include
file, which is used in the U-Boot recipe.
The SPL file type is set to "null" by default in the
u-boot.inc
file as follows:
# Some versions of u-boot build an SPL (Second Program Loader) image that # should be packaged along with the u-boot binary as well as placed in the # deploy directory. For those versions they can set the following variables # to allow packaging the SPL. SPL_BINARY ?= "" SPL_BINARYNAME ?= "${@os.path.basename(d.getVar("SPL_BINARY"))}" SPL_IMAGE ?= "${SPL_BINARYNAME}-${MACHINE}-${PV}-${PR}" SPL_SYMLINK ?= "${SPL_BINARYNAME}-${MACHINE}"
The SPL_BINARY
variable helps form
various SPL_*
variables used by
the OpenEmbedded build system.
See the BeagleBone machine configuration example in the
"Creating a new BSP Layer Using the bitbake-layers
Script"
section in the Yocto Project Board Support Package
Developer's Guide for additional information.
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 (e.g.
patch
files).
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.
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 ${
S
}
.
Here are options specific to recipes building code from a revision control system:
mindate
-
Apply the patch only if
SRCDATE
is equal to or greater than mindate
.
maxdate
-
Apply the patch only if SRCDATE
is not later than mindate
.
minrev
-
Apply the patch only if SRCREV
is equal to or greater than minrev
.
maxrev
-
Apply the patch only if SRCREV
is not later than maxrev
.
rev
-
Apply the patch only if SRCREV
is equal to rev
.
notrev
-
Apply the patch only if SRCREV
is not equal to rev
.
Here are some additional options worth mentioning:
unpack
- Controls
whether or not to unpack the file if it is an archive.
The default action is to unpack the file.
destsuffix
- Places the file
(or extracts its contents) into the specified
subdirectory of WORKDIR
when the Git fetcher is used.
subdir
- Places the file
(or extracts its contents) into the specified
subdirectory of WORKDIR
when the local (file://
)
fetcher is used.
localdir
- Places the file
(or extracts its contents) into the specified
subdirectory of WORKDIR
when
the CVS fetcher is used.
subpath
-
Limits the checkout to a specific subpath of the
tree when using the Git fetcher is used.
name
- Specifies a
name to be used for association with SRC_URI
checksums
when you have more than one file specified in SRC_URI
.
downloadfilename
- Specifies
the filename used when storing the downloaded file.
By default, the OpenEmbedded build system automatically detects whether
SRC_URI
contains files that are machine-specific.
If so, the build system automatically changes
PACKAGE_ARCH
.
Setting this variable to "0" disables this behavior.
The date of the source code used to build the package. This variable applies only if the source was fetched from a Source Code Manager (SCM).
Returns the version string of the current package.
This string is used to help define the value of
PV
.
The SRCPV
variable is defined in the
meta/conf/bitbake.conf
configuration
file in the
Source Directory
as follows:
SRCPV = "${@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}"
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.
SRCREV
, see the
AUTOREV
variable description and the
"Automatically Incrementing a Binary Package Revision Number"
section, which is in the Yocto Project Development
Tasks Manual.
The directory for the shared state cache.
If set to "1", allows fetches from
mirrors that are specified in
SSTATE_MIRRORS
to work even when fetching from the network is
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.
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
state (sstate) 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.
When pointing to sstate build artifacts on another machine
that uses a different GCC version for native builds,
you must configure SSTATE_MIRROR
with a regular expression that maps local search paths
to server paths.
The paths need to take into account
NATIVELSBSTRING
set by the
uninative
class.
For example, the following maps the local search path
universal-4.9
to the server-provided
path server_url_sstate_path
:
SSTATE_MIRRORS ?= file://universal-4.9/(.*) http://server_url_sstate_path
/universal-4.8/\1 \n
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"
Controls the list of files the OpenEmbedded build system scans for hardcoded installation paths. The variable uses a space-separated list of filenames (not paths) with standard wildcard characters allowed.
During a build, the OpenEmbedded build system creates a
shared state (sstate) object during the first stage of
preparing the sysroots. That 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.
Typically, recipes add files they want to be scanned to the
value of SSTATE_SCAN_FILES
rather than
the variable being comprehensively set. The
sstate
class specifies the default list of files.
For details on the process, see the
staging
class.
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 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
).
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.
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.
Specifies the path to the
/usr/bin
subdirectory of the
sysroot directory for the build 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
).
Specifies the path to the /usr/share
subdirectory of the sysroot directory for the build host.
Helps construct the recipe-sysroots
directory, which is used during packaging.
For information on how staging for recipe-specific
sysroots occurs, see the
do_populate_sysroot
task, the
"Sharing Files Between Recipes"
section in the Yocto Project Development Tasks Manual, the
"Configuration, Compilation, and Staging"
section in the Yocto Project Overview and Concepts Manual,
and the
SYSROOT_DIRS
variable.
STAGING_DIR
directory because
the OpenEmbedded build system
manages the directory automatically.
Instead, files should be installed to
${
D
}
within your recipe's
do_install
task and then the OpenEmbedded build system will
stage a subset of those files into the sysroot.
Specifies the path to the sysroot directory for the system
on which the component is built to run (the system that
hosts the component).
For most recipes, this sysroot is the one in which that
recipe's
do_populate_sysroot
task copies files.
Exceptions include -native
recipes,
where the do_populate_sysroot
task
instead uses
STAGING_DIR_NATIVE
.
Depending on the type of recipe and the build target,
STAGING_DIR_HOST
can have the
following values:
For recipes building for the target machine, the value is "${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.
Thus, the emphasis is 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.
Specifies the path to the sysroot directory used when building components that run on the build host itself.
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.
Specifies the path to the /etc
subdirectory of the sysroot directory for the
build 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
).
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 build host.
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.
The directory with kernel headers that are required to build out-of-tree modules.
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 build host.
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 in the Yocto Project Overview and Concepts Manual.
See STAMPS_DIR
,
MULTIMACH_TARGET_SYS
,
PN
,
EXTENDPE
,
PV
, and
PR
for related variable
information.
Specifies the base directory in which the OpenEmbedded
build system places stamps.
The default directory is
${TMPDIR}/stamps
.
The minimal command and arguments to run
strip
, which is used to strip
symbols.
The short (72 characters or less) summary of the binary package for packaging
systems such as opkg
, rpm
, or
dpkg
.
By default, SUMMARY
is used to define
the DESCRIPTION
variable if DESCRIPTION
is not set
in the recipe.
The directory in which files checked out of a Subversion system are stored.
Specifies the kernel boot default console. If you want to use a console other than the default, set this variable in your recipe as follows where "X" is the console number you want to use:
SYSLINUX_DEFAULT_CONSOLE = "console=ttyX"
The
syslinux
class initially sets this variable to null but then checks
for a value later.
Lists additional options to add to the syslinux file.
You need to set this variable in your recipe.
If you want to list multiple options, separate the options
with a semicolon character (;
).
The
syslinux
class uses this variable to create a set of options.
Specifies the alternate serial port or turns it off.
To turn off serial, set this variable to an empty string
in your recipe.
The variable's default value is set in the
syslinux
class as follows:
SYSLINUX_SERIAL ?= "0 115200"
The class checks for and uses the variable as needed.
An .LSS
file used as the background
for the VGA boot menu when you use the boot menu.
You need to set this variable in your recipe.
The
syslinux
class checks for this variable and if found, the
OpenEmbedded build system installs the splash screen.
Specifies the alternate console=tty... kernel boot argument.
The variable's default value is set in the
syslinux
class as follows:
SYSLINUX_SERIAL_TTY ?= "console=ttyS0,115200"
The class checks for and uses the variable as needed.
Points to the temporary directory under the work directory
(default
"${
WORKDIR
}/sysroot-destdir
")
where the files populated into the sysroot are assembled
during 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} \ "
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 \ "
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} \ ${localstatedir} \ "
-native
recipes
run directly from the sysroot
(STAGING_DIR_NATIVE
),
which is why additional directories containing program
executables and supporting files need to be staged.
A list of functions to execute after files are staged into the sysroot. These functions are usually used to apply additional processing on the staged files, or to stage additional files.
When inheriting the
systemd
class, this variable specifies whether the specified service
in
SYSTEMD_SERVICE
should start automatically or not.
By default, the service is enabled to automatically start
at boot time.
The default setting is in the
systemd
class as follows:
SYSTEMD_AUTO_ENABLE ??= "enable"
You can disable the service by setting the variable to "disable".
When
EFI_PROVIDER
is set to "systemd-boot", the
SYSTEMD_BOOT_CFG
variable specifies the
configuration file that should be used.
By default, the
systemd-boot
class sets the SYSTEMD_BOOT_CFG
as
follows:
SYSTEMD_BOOT_CFG ?= "${S}/loader.conf"
For information on Systemd-boot, see the Systemd-boot documentation.
When
EFI_PROVIDER
is set to "systemd-boot", the
SYSTEMD_BOOT_ENTRIES
variable specifies
a list of entry files
(*.conf
) to install that contain
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.
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.
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 ?= "${PN}"
If these unit files are not in this recipe's main
package, you need to use
SYSTEMD_PACKAGES
to list the package
or packages in which the build system can find the systemd
unit files.
When inheriting the
systemd
class, this variable specifies the systemd service name for
a package.
When you specify this file in your recipe, use a package name override to indicate the package to which the value applies. Here is an example from the connman recipe:
SYSTEMD_SERVICE_${PN} = "connman.service"
When using
SysVinit,
specifies a space-separated list of the virtual terminals
that should run 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).
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 = "${WORKDIR}/temp"
The WORKDIR
is the directory into which BitBake unpacks and builds the
recipe.
The default bitbake.conf
file sets this variable.
The T
variable is not to be confused with
the TMPDIR
variable,
which points to the root of the directory tree where BitBake
places the output of an entire build.
The target machine's architecture. The OpenEmbedded build system supports many architectures. Here is an example list of architectures supported. This list is by no means complete as the architecture is configurable:
arm i586 x86_64 powerpc powerpc64 mips mipsel
For additional information on machine architectures, see
the
TUNE_ARCH
variable.
Specifies architecture-specific assembler flags for the
target system.
TARGET_AS_ARCH
is initialized from
TUNE_ASARGS
by default in the BitBake configuration file
(meta/conf/bitbake.conf
):
TARGET_AS_ARCH = "${TUNE_ASARGS}"
Specifies architecture-specific C compiler flags for the
target system.
TARGET_CC_ARCH
is initialized from
TUNE_CCARGS
by default.
LDFLAGS
to TARGET_CC_ARCH
in recipes that build software for the target that
would not otherwise respect the exported
LDFLAGS
variable.
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.
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.
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.
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.
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 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 = "${TUNE_LDARGS}"
Specifies the flags to pass to the linker when building
for the target.
When building in the target context,
LDFLAGS
is set to the value of this variable by default.
Additionally, the SDK's environment setup script sets
the
LDFLAGS
variable in the environment to the
TARGET_LDFLAGS
value so that
executables built using the SDK also have the flags
applied.
Specifies the target's operating system. The variable can be set to "linux" for glibc-based systems (GNU C Library) and to "linux-musl" for musl libc. For ARM/EABI targets, "linux-gnueabi" and "linux-musleabi" possible values exist.
Specifies the prefix used for the toolchain binary target tools.
Depending on the type of recipe and the build target,
TARGET_PREFIX
is set as follows:
For recipes building for the target machine, the value is "${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
.
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.
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".
Specifies the name of the target vendor.
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", "musl", "newlib", or "baremetal"
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.
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.
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 Yocto Project release
for the specific components with which the toolchain
must be compatible.
To access the Release Notes, go to the
Downloads
page on the Yocto Project website and click on the
"RELEASE INFORMATION" link for the appropriate
release.
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 musl
.
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
http://github.com/MentorEmbedded/meta-sourcery/.
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.
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/${PN}"
.
Specifies to export the tests only. Set this variable to "1" if you do not want to run the tests but you want them to be exported in a manner that you to run them outside of the build system.
Holds the SSH log and the boot log for QEMU machines.
The TEST_LOG_DIR
variable defaults
to "${WORKDIR}/testimage"
.
log.do_testimage
), which is in
the ${WORKDIR}/temp/
directory.
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.
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.
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 Tasks Manual.
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"
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.
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).
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
.
Specifies the target controller to use when running tests against a test image. The default controller to use is "QemuTarget":
TEST_TARGET = "QemuTarget"
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
:
"QemuTarget": Boots a QEMU image and runs the tests. See the "Enabling Runtime Tests on QEMU" section in the Yocto Project Development Tasks Manual for more information.
"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 "SimpleRemoteTarget".
meta/lib/oeqa/controllers/simpleremote.py
.
For information on running tests on hardware, see the "Enabling Runtime Tests on Hardware" section in the Yocto Project Development Tasks Manual.
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.
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.
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 Tasks Manual.
Automatically runs the series of automated tests for
images when an image is successfully built.
Setting TESTIMAGE_AUTO
to "1"
causes any image that successfully builds to automatically
boot under QEMU.
Using the variable also adds in dependencies so that any
SDK for which testing is requested is automatically built
first.
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:
TESTIMAGE_AUTO = "1"
For more information on enabling, running, and writing
these tests, see the
"Performing Automated Runtime Testing"
section in the Yocto Project Development Tasks Manual and
the
"testimage*.bbclass
"
section.
The directory in which the file BitBake is currently parsing is located. Do not manually set this variable.
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).
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.
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 Application Development and the Extensible Software Development Kit (eSDK) manual for more information.
For background information on cross-development toolchains in the Yocto Project development environment, see the "Cross-Development Toolchain Generation" section in the Yocto Project Overview and Concepts Manual. For information on setting up a cross-development environment, see the Yocto Project Application Development and the Extensible Software Development Kit (eSDK) manual.
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.
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 Application Development and the Extensible Software Development Kit (eSDK) manual for more information.
For background information on cross-development toolchains in the Yocto Project development environment, see the "Cross-Development Toolchain Generation" section in the Yocto Project Overview and Concepts Manual. For information on setting up a cross-development environment, see the Yocto Project Application Development and the Extensible Software Development Kit (eSDK) manual.
The top-level
Build Directory.
BitBake automatically sets this variable when you
initialize your build environment using
oe-init-build-env
.
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.
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 = "${TUNE_ARCH}"
The following list, which is by no means complete since architectures are configurable, shows supported machine architectures:
arm i586 x86_64 powerpc powerpc64 mips mipsel
Specifies architecture-specific assembler flags for
the target system.
The set of flags is based on the selected tune features.
TUNE_ASARGS
is set using
the tune include files, which are typically under
meta/conf/machine/include/
and are
influenced through
TUNE_FEATURES
.
For example, the
meta/conf/machine/include/x86/arch-x86.inc
file defines the flags for the x86 architecture as follows:
TUNE_ASARGS += "${@bb.utils.contains("TUNE_FEATURES", "mx32", "-x32", "", d)}"
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
.
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 += "${@bb.utils.contains("TUNE_FEATURES", "mx32", "-m elf32_x86_64", "", d)}"
Features used to "tune" a compiler for optimal use
given a specific processor.
The features are defined within the tune files and allow
arguments (i.e. TUNE_*ARGS
) to be
dynamically generated based on the features.
The OpenEmbedded build system verifies the features to be sure they are not conflicting and that they are supported.
The BitBake configuration file
(meta/conf/bitbake.conf
) defines
TUNE_FEATURES
as follows:
TUNE_FEATURES ??= "${TUNE_FEATURES_tune-${DEFAULTTUNE}}"
See the
DEFAULTTUNE
variable for more information.
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"
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.
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.
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.
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"
feature
]
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.
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.
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.
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.
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"
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.
Specifies the target called in the
Makefile
.
The default target is "all".
Points to the generated U-Boot extension.
For example, u-boot.sb
has a
.sb
extension.
The default U-Boot extension is
.bin
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.
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.
For recipes inheriting the
update-rc.d
class, UPDATERCPN
specifies
the package that contains the initscript that is
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.
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"
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"
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"
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 Tasks Manual for information on how to use this variable.
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.
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.
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.
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"
USERADDEXTENSION
variable to "useradd-staticids" causes the build system
to use static gid
values.
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 = "${PN}"
USERADD_PACKAGES
variable,
you need to set one or more of the
USERADD_PARAM
,
GROUPADD_PARAM
,
or
GROUPMEMS_PARAM
variables.
When inheriting the
useradd
class, this variable
specifies for a package what parameters should pass
to the useradd
command
if you add a user to the system when the package
is installed.
Here is an example from the dbus
recipe:
USERADD_PARAM_${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
http://linux.die.net/man/8/useradd.
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"
USERADDEXTENSION
variable to "useradd-staticids" causes the build system
to use static uid
values.
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"
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.
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.
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.
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.
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 Using Wic"
section in the Yocto Project Development Tasks Manual.
For details on the kickstart file format, see the
"OpenEmbedded Kickstart (.wks
) Reference
Chapter.
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:
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
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".