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-rw-r--r--bitbake/doc/manual/usermanual.xml20
1 files changed, 19 insertions, 1 deletions
diff --git a/bitbake/doc/manual/usermanual.xml b/bitbake/doc/manual/usermanual.xml
index e776b43c41..6781a71a62 100644
--- a/bitbake/doc/manual/usermanual.xml
+++ b/bitbake/doc/manual/usermanual.xml
@@ -138,6 +138,24 @@ share common metadata between many packages.</para></listitem>
138will be introduced.</para> 138will be introduced.</para>
139 </section> 139 </section>
140 <section> 140 <section>
141 <title>Appending and Prepending (override style syntax)</title>
142 <para><screen><varname>B</varname> = "bval"
143<varname>B_append</varname> = " additional data"
144<varname>C</varname> = "cval"
145<varname>C_prepend</varname> = "additional data "</screen></para>
146 <para>This example results in <varname>B</varname> becoming <literal>bval additional data</literal>
147and <varname>C</varname> becoming <literal>additional data cval</literal>. Note the spaces in the append.
148Unlike the += operator, additional space is not automatically added. You must take steps to add space
149yourself.</para>
150 </section>
151 <section>
152 <title>Removing (override style syntax)</title>
153 <para><screen><varname>FOO</varname> = "123 456 789 123456 123 456 123 456"
154<varname>FOO_remove</varname> = "123"
155<varname>FOO_remove</varname> = "456"</screen></para>
156 <para>In this example, <varname>FOO</varname> is now <literal>789 123456</literal>.</para>
157 </section>
158 <section>
141 <title>Conditional metadata set</title> 159 <title>Conditional metadata set</title>
142 <para>OVERRIDES is a <quote>:</quote> separated variable containing each item you want to satisfy conditions. So, if you have a variable which is conditional on <quote>arm</quote>, and <quote>arm</quote> is in OVERRIDES, then the <quote>arm</quote> specific version of the variable is used rather than the non-conditional version. Example:</para> 160 <para>OVERRIDES is a <quote>:</quote> separated variable containing each item you want to satisfy conditions. So, if you have a variable which is conditional on <quote>arm</quote>, and <quote>arm</quote> is in OVERRIDES, then the <quote>arm</quote> specific version of the variable is used rather than the non-conditional version. Example:</para>
143 <para><screen><varname>OVERRIDES</varname> = "architecture:os:machine" 161 <para><screen><varname>OVERRIDES</varname> = "architecture:os:machine"
@@ -536,7 +554,7 @@ options:
536 <example> 554 <example>
537 <title>Generating dependency graphs</title> 555 <title>Generating dependency graphs</title>
538 <para>BitBake is able to generate dependency graphs using the dot syntax. These graphs can be converted 556 <para>BitBake is able to generate dependency graphs using the dot syntax. These graphs can be converted
539to images using the <application>dot</application> application from <ulink url="http://www.graphviz.org">Graphviz</ulink>. 557to images using the <application>dot</application> application from <ulink url="http://www.graphviz.org">Graphviz</ulink>.
540Two files will be written into the current working directory, <emphasis>depends.dot</emphasis> containing dependency information at the package level and <emphasis>task-depends.dot</emphasis> containing a breakdown of the dependencies at the task level. To stop depending on common depends, one can use the <prompt>-I depend</prompt> to omit these from the graph. This can lead to more readable graphs. This way, <varname>DEPENDS</varname> from inherited classes such as base.bbclass can be removed from the graph.</para> 558Two files will be written into the current working directory, <emphasis>depends.dot</emphasis> containing dependency information at the package level and <emphasis>task-depends.dot</emphasis> containing a breakdown of the dependencies at the task level. To stop depending on common depends, one can use the <prompt>-I depend</prompt> to omit these from the graph. This can lead to more readable graphs. This way, <varname>DEPENDS</varname> from inherited classes such as base.bbclass can be removed from the graph.</para>
541 <screen><prompt>$ </prompt>bitbake -g blah</screen> 559 <screen><prompt>$ </prompt>bitbake -g blah</screen>
542 <screen><prompt>$ </prompt>bitbake -g -I virtual/whatever -I bloom blah</screen> 560 <screen><prompt>$ </prompt>bitbake -g -I virtual/whatever -I bloom blah</screen>