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-rw-r--r--documentation/ref-manual/ref-classes.xml43
1 files changed, 23 insertions, 20 deletions
diff --git a/documentation/ref-manual/ref-classes.xml b/documentation/ref-manual/ref-classes.xml
index 27edfde33d..e65004f8ff 100644
--- a/documentation/ref-manual/ref-classes.xml
+++ b/documentation/ref-manual/ref-classes.xml
@@ -6,36 +6,39 @@
6<title>Classes</title> 6<title>Classes</title>
7 7
8<para> 8<para>
9 Class files are used to abstract common functionality and share it amongst multiple 9 Class files are used to abstract common functionality and share it amongst
10 <filename>.bb</filename> files. 10 multiple recipe (<filename>.bb</filename>) files.
11 To use a class file, you simply make sure the recipe inherits the class.
12 In most cases, when a recipe inherits a class it is enough to enable its
13 features.
14 There are cases, however, where in the recipe you might need to set
15 variables or override some default behavior.
16</para>
17
18<para>
11 Any <ulink url='&YOCTO_DOCS_DEV_URL;#metadata'>Metadata</ulink> usually 19 Any <ulink url='&YOCTO_DOCS_DEV_URL;#metadata'>Metadata</ulink> usually
12 found in a <filename>.bb</filename> file can also be placed in a class 20 found in a recipe can also be placed in a class file.
13 file. 21 Class files are identified by the extension <filename>.bbclass</filename>
14 Class files are identified by the extension <filename>.bbclass</filename> and are usually placed 22 and are usually placed in a <filename>classes/</filename> directory beneath
15 in a <filename>classes/</filename> directory beneath the 23 the <filename>meta*/</filename> directory found in the
16 <filename>meta*/</filename> directory found in the
17 <ulink url='&YOCTO_DOCS_DEV_URL;#source-directory'>Source Directory</ulink>. 24 <ulink url='&YOCTO_DOCS_DEV_URL;#source-directory'>Source Directory</ulink>.
18 Class files can also be pointed to by 25 Class files can also be pointed to by
19 <link linkend='var-BUILDDIR'><filename>BUILDDIR</filename></link> 26 <link linkend='var-BUILDDIR'><filename>BUILDDIR</filename></link>
20 (e.g. <filename>build/</filename>) in the same way as 27 (e.g. <filename>build/</filename>) in the same way as
21 <filename>.conf</filename> files in the <filename>conf</filename> directory. 28 <filename>.conf</filename> files in the <filename>conf</filename> directory.
22 Class files are searched for in <link linkend='var-BBPATH'><filename>BBPATH</filename></link> 29 Class files are searched for in
23 using the same method by which <filename>.conf</filename> files are searched. 30 <link linkend='var-BBPATH'><filename>BBPATH</filename></link>
24</para> 31 using the same method by which <filename>.conf</filename> files are
25 32 searched.
26<para>
27 In most cases inheriting the class is enough to enable its features, although
28 for some classes you might need to set variables or override some of the
29 default behavior.
30</para> 33</para>
31 34
32<para> 35<para>
33 This chapter discusses only the most useful and important classes. 36 This chapter discusses only the most useful and important classes.
34 Other classes do exist within the <filename>meta/classes</filename> 37 Other classes do exist within the <filename>meta/classes</filename>
35 directory in the 38 directory in the
36 <ulink url='&YOCTO_DOCS_DEV_URL;#source-directory'>Source Directory</ulink>. 39 <ulink url='&YOCTO_DOCS_DEV_URL;#source-directory'>Source Directory</ulink>.
37 You can reference the <filename>.bbclass</filename> files directly 40 You can reference the <filename>.bbclass</filename> files directly
38 for more information. 41 for more information.
39</para> 42</para>
40 43
41<section id='ref-classes-base'> 44<section id='ref-classes-base'>