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-rw-r--r--documentation/ref-manual/ref-features.rst30
1 files changed, 15 insertions, 15 deletions
diff --git a/documentation/ref-manual/ref-features.rst b/documentation/ref-manual/ref-features.rst
index 1aa57a27d4..0e901edaeb 100644
--- a/documentation/ref-manual/ref-features.rst
+++ b/documentation/ref-manual/ref-features.rst
@@ -24,7 +24,7 @@ included if the distribution itself does not support them.
24 24
25One method you can use to determine which recipes are checking to see if 25One method you can use to determine which recipes are checking to see if
26a particular feature is contained or not is to ``grep`` through the 26a particular feature is contained or not is to ``grep`` through the
27`Metadata <#metadata>`__ for the feature. Here is an example that 27:term:`Metadata` for the feature. Here is an example that
28discovers the recipes whose build is potentially changed based on a 28discovers the recipes whose build is potentially changed based on a
29given feature: $ cd poky $ git grep 29given feature: $ cd poky $ git grep
30'contains.*MACHINE_FEATURES.*feature' 30'contains.*MACHINE_FEATURES.*feature'
@@ -35,12 +35,12 @@ Machine Features
35================ 35================
36 36
37The items below are features you can use with 37The items below are features you can use with
38```MACHINE_FEATURES`` <#var-MACHINE_FEATURES>`__. Features do not have a 38:term:`MACHINE_FEATURES`. Features do not have a
39one-to-one correspondence to packages, and they can go beyond simply 39one-to-one correspondence to packages, and they can go beyond simply
40controlling the installation of a package or packages. Sometimes a 40controlling the installation of a package or packages. Sometimes a
41feature can influence how certain recipes are built. For example, a 41feature can influence how certain recipes are built. For example, a
42feature might determine whether a particular configure option is 42feature might determine whether a particular configure option is
43specified within the ```do_configure`` <#ref-tasks-configure>`__ task 43specified within the :ref:`ref-tasks-configure` task
44for a particular recipe. 44for a particular recipe.
45 45
46This feature list only represents features as shipped with the Yocto 46This feature list only represents features as shipped with the Yocto
@@ -92,18 +92,18 @@ Distro Features
92=============== 92===============
93 93
94The items below are features you can use with 94The items below are features you can use with
95```DISTRO_FEATURES`` <#var-DISTRO_FEATURES>`__ to enable features across 95:term:`DISTRO_FEATURES` to enable features across
96your distribution. Features do not have a one-to-one correspondence to 96your distribution. Features do not have a one-to-one correspondence to
97packages, and they can go beyond simply controlling the installation of 97packages, and they can go beyond simply controlling the installation of
98a package or packages. In most cases, the presence or absence of a 98a package or packages. In most cases, the presence or absence of a
99feature translates to the appropriate option supplied to the configure 99feature translates to the appropriate option supplied to the configure
100script during the ```do_configure`` <#ref-tasks-configure>`__ task for 100script during the :ref:`ref-tasks-configure` task for
101the recipes that optionally support the feature. 101the recipes that optionally support the feature.
102 102
103Some distro features are also machine features. These select features 103Some distro features are also machine features. These select features
104make sense to be controlled both at the machine and distribution 104make sense to be controlled both at the machine and distribution
105configuration level. See the 105configuration level. See the
106```COMBINED_FEATURES`` <#var-COMBINED_FEATURES>`__ variable for more 106:term:`COMBINED_FEATURES` variable for more
107information. 107information.
108 108
109This list only represents features as shipped with the Yocto Project 109This list only represents features as shipped with the Yocto Project
@@ -189,8 +189,8 @@ Image Features
189============== 189==============
190 190
191The contents of images generated by the OpenEmbedded build system can be 191The contents of images generated by the OpenEmbedded build system can be
192controlled by the ```IMAGE_FEATURES`` <#var-IMAGE_FEATURES>`__ and 192controlled by the :term:`IMAGE_FEATURES` and
193```EXTRA_IMAGE_FEATURES`` <#var-EXTRA_IMAGE_FEATURES>`__ variables that 193:term:`EXTRA_IMAGE_FEATURES` variables that
194you typically configure in your image recipes. Through these variables, 194you typically configure in your image recipes. Through these variables,
195you can add several different predefined packages such as development 195you can add several different predefined packages such as development
196utilities or packages with debug information needed to investigate 196utilities or packages with debug information needed to investigate
@@ -254,7 +254,7 @@ The following image features are available for all images:
254 a given image. 254 a given image.
255 255
256Some image features are available only when you inherit the 256Some image features are available only when you inherit the
257```core-image`` <#ref-classes-core-image>`__ class. The current list of 257:ref:`core-image <ref-classes-core-image>` class. The current list of
258these valid features is as follows: 258these valid features is as follows:
259 259
260- *hwcodecs:* Installs hardware acceleration codecs. 260- *hwcodecs:* Installs hardware acceleration codecs.
@@ -299,8 +299,8 @@ Feature Backfilling
299=================== 299===================
300 300
301Sometimes it is necessary in the OpenEmbedded build system to extend 301Sometimes it is necessary in the OpenEmbedded build system to extend
302```MACHINE_FEATURES`` <#var-MACHINE_FEATURES>`__ or 302:term:`MACHINE_FEATURES` or
303```DISTRO_FEATURES`` <#var-DISTRO_FEATURES>`__ to control functionality 303:term:`DISTRO_FEATURES` to control functionality
304that was previously enabled and not able to be disabled. For these 304that was previously enabled and not able to be disabled. For these
305cases, we need to add an additional feature item to appear in one of 305cases, we need to add an additional feature item to appear in one of
306these variables, but we do not want to force developers who have 306these variables, but we do not want to force developers who have
@@ -310,8 +310,8 @@ Thus, the OpenEmbedded build system has a mechanism to automatically
310"backfill" these added features into existing distro or machine 310"backfill" these added features into existing distro or machine
311configurations. You can see the list of features for which this is done 311configurations. You can see the list of features for which this is done
312by finding the 312by finding the
313```DISTRO_FEATURES_BACKFILL`` <#var-DISTRO_FEATURES_BACKFILL>`__ and 313:term:`DISTRO_FEATURES_BACKFILL` and
314```MACHINE_FEATURES_BACKFILL`` <#var-MACHINE_FEATURES_BACKFILL>`__ 314:term:`MACHINE_FEATURES_BACKFILL`
315variables in the ``meta/conf/bitbake.conf`` file. 315variables in the ``meta/conf/bitbake.conf`` file.
316 316
317Because such features are backfilled by default into all configurations 317Because such features are backfilled by default into all configurations
@@ -319,9 +319,9 @@ as described in the previous paragraph, developers who wish to disable
319the new features need to be able to selectively prevent the backfilling 319the new features need to be able to selectively prevent the backfilling
320from occurring. They can do this by adding the undesired feature or 320from occurring. They can do this by adding the undesired feature or
321features to the 321features to the
322```DISTRO_FEATURES_BACKFILL_CONSIDERED`` <#var-DISTRO_FEATURES_BACKFILL_CONSIDERED>`__ 322:term:`DISTRO_FEATURES_BACKFILL_CONSIDERED`
323or 323or
324```MACHINE_FEATURES_BACKFILL_CONSIDERED`` <#var-MACHINE_FEATURES_BACKFILL_CONSIDERED>`__ 324:term:`MACHINE_FEATURES_BACKFILL_CONSIDERED`
325variables for distro features and machine features respectively. 325variables for distro features and machine features respectively.
326 326
327Here are two examples to help illustrate feature backfilling: 327Here are two examples to help illustrate feature backfilling: