path: root/documentation/poky-ref-manual
diff options
authorScott Rifenbark <>2012-02-28 12:21:35 -0600
committerRichard Purdie <>2012-03-08 12:08:04 -0800
commit05cff8adcb22b43fa8135a37af4799cd00a8d11b (patch)
tree9f6dfa1151eeb76e205e10a2dc4fb67aebf11d9f /documentation/poky-ref-manual
parent36e3daf7f924fbf15ab9c1764c424046adffff5e (diff)
documentation/poky-ref-manual/ref-variables.xml: B and BBCLASSEXTEND
Added two new variable entries. This is part of the fix needed as a result of the feedback from two Community members inside Intel whose feedback was initially reported by Darren Hart. Reported-by: Inaky Perez-Gonzales <> Reported-by: Mohamed Abbas <> (From yocto-docs rev: ccabb9c905e7a1c9a211f805f8a326048903b7b0) Signed-off-by: Scott Rifenbark <> Signed-off-by: Richard Purdie <>
Diffstat (limited to 'documentation/poky-ref-manual')
1 files changed, 47 insertions, 3 deletions
diff --git a/documentation/poky-ref-manual/ref-variables.xml b/documentation/poky-ref-manual/ref-variables.xml
index 1e31e0a3ab..ec747bf5f9 100644
--- a/documentation/poky-ref-manual/ref-variables.xml
+++ b/documentation/poky-ref-manual/ref-variables.xml
@@ -16,7 +16,7 @@
<link linkend='var-AUTHOR'>A</link>
- <link linkend='var-BAD_RECOMMENDATIONS'>B</link>
+ <link linkend='var-B'>B</link>
<link linkend='var-CFLAGS'>C</link>
<link linkend='var-D'>D</link>
<link linkend='var-ENABLE_BINARY_LOCALE_GENERATION'>E</link>
@@ -64,14 +64,58 @@
<glossdiv id='var-glossary-b'><title>B</title>
+ <glossentry id='var-B'><glossterm>B</glossterm>
+ <glossdef>
+ <para>
+ The directory in which the Yocto Project build system places
+ generated objects during a recipe's build process.
+ By default, this directory is the same as the <link linkend='var-S'><filename>S</filename></link>
+ directory:
+ <literallayout class='monospaced'>
+ B = ${WORKDIR}/${BPN}-{PV}/
+ </literallayout>
+ You can separate the source directory (<filename>S</filename>) and the directory pointed to
+ by the <filename>B</filename> variable.
+ In general, <filename>autotools</filename>, recipes such as <filename>gcc</filename>,
+ and some kernel recipes separate these directories by default.
+ </para>
+ </glossdef>
+ </glossentry>
<glossentry id='var-BAD_RECOMMENDATIONS'><glossterm>BAD_RECOMMENDATIONS</glossterm>
- <para>A list of packages not to install despite being recommended by a recipe.
+ <para>
+ A list of packages not to install despite being recommended by a recipe.
Support for this variable exists only for images that use the
- <filename>ipkg</filename> packaging system.</para>
+ <filename>ipkg</filename> packaging system.
+ </para>
+ <glossentry id='var-BBCLASSEXTEND'><glossterm>BBCLASSEXTEND</glossterm>
+ <glossdef>
+ <para>
+ Allows you to extend a recipe so that it builds variants of the software.
+ Common variants for recipes exist such as "natives" like <filename>quilt-native</filename>,
+ which is a copy of quilt built to run on the build system;
+ "crosses" such as <filename>gcc-cross</filename>,
+ which is a compiler built to run on the build machine but produces binaries
+ that run on the target <link linkend='var-MACHINE'><filename>MACHINE</filename></link>;
+ "nativesdk", which targets the SDK machine instead of <filename>MACHINE</filename>;
+ and "mulitlibs" in the form "<filename>multilib:&lt;multilib_name&gt;</filename>".
+ </para>
+ <para>
+ 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:
+ <literallayout class='monospaced'>
+ BBCLASSEXTEND = "native nativesdk"
+ BBCLASSEXTEND = "multilib:&lt;multilib_name&gt;"
+ </literallayout>
+ </para>
+ </glossdef>
+ </glossentry>
<glossentry id='var-BBMASK'><glossterm>BBMASK</glossterm>
<para>Prevents BitBake from processing recipes and recipe append files.