<para>Length of the mapped buffer. This must be the same
value as given to <function>mmap()</function> and returned by the
driver in the &v4l2-buffer; <structfield>length</structfield>
-field.</para>
+field for the single-planar API and in the &v4l2-plane;
+<structfield>length</structfield> field for the multi-planar API.</para>
</listitem>
</varlistentry>
</variablelist>