ref-manual: Updated the RDEPENDS variable to include syntax

Fixes [YOCTO #4987]

This variable supports some boolean operators that we are not
showing for supporting versioned dependencies.  I added the
explanation for them.  There will be other variables affected
later once we settle on the changes here.

(From yocto-docs rev: e5c1e66d670c708012bd5ab51aa94f87426f57e2)

Signed-off-by: Scott Rifenbark <scott.m.rifenbark@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 26 insertions, 0 deletions

diff --git a/documentation/ref-manual/ref-variables.xml b/documentation/ref-manual/ref-variables.xml
index 2ba4882d8f..51f4966349 100644
--- a/documentation/ref-manual/ref-variables.xml
+++ b/documentation/ref-manual/ref-variables.xml
@@ -4133,6 +4133,32 @@ recipes-graphics/xorg-font/font-alias_1.0.3.bb:PR = "${INC_PR}.3"
                 </para>
 
                 <para>
+                    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 <filename>RDEPENDS</filename> variable:
+                    <literallayout class='monospaced'>
+     RDEPENDS_${PN} = "&lt;package&gt; (&lt;operator&gt; &lt;version&gt;)"
+                    </literallayout>
+                    For <filename>operator</filename>, you can specify the
+                    following:
+                    <literallayout class='monospaced'>
+     =
+     &lt;
+     &gt;
+     &lt;=
+     &gt;=
+                    </literallayout>
+                    For example, the following sets up a dependency on version
+                    1.2 or greater of the package <filename>foo</filename>:
+                    <literallayout class='monospaced'>
+     RDEPENDS_${PN} = "foo (>= 1.2)"
+                    </literallayout>
+                </para>
+
+                <para>
                     For information on build-time dependencies, see the
                     <link linkend='var-DEPENDS'><filename>DEPENDS</filename></link>
                     variable.