PERFORCE change 102675 for review

[Gabor Kovesdan]

http://perforce.freebsd.org/chv.cgi?CH=102675

Change 102675 by gabor at gabor_spitfire on 2006/07/28 18:43:49

	Document the IS_JAILED macro and the changed OSVERSION behavior,
	I changed for the DESTDIR support.

Affected files ...

.. //depot/projects/soc2006/gabor_docs/porters-handbook/book.sgml#12 edit

Differences ...

==== //depot/projects/soc2006/gabor_docs/porters-handbook/book.sgml#12 (text+ko) ====

@@ -3941,6 +3941,25 @@
       <para>There are some more things you have to take into account when you
 	create a port.  This section explains the most common of those.</para>
 
+      <sect1 id="building-in-jails">
+        <title>Building in jails</title>
+
+	<para>There might be cases where you want to know if the build is
+	  running from a jailed environment or not.  There is the
+	  <makevar>IS_JAILED</makevar> variable for this case.  It is defined
+	  in <filename>bsd.port.mk</filename> when you are jailed.  For
+	  debugging purposes, you can manually define <makevar>IS_JAILED</makevar>
+	  to pretend that you are imprisoned.</para>
+
+	<para>Note, that the behavior of <makevar>OSVERSION</makevar> has been
+	  changed recently.  Now, it gets the <link
+	   linkend="freebsd-versions"><literal>__FreeBSD_version</literal></link>
+	  from the userland, since it makes more sense for the ports, than the
+	  kernel.  You can still override it, if you really have to get it from
+	  the kernel.</para>
+
+      </sect1>
+
       <sect1 id="porting-shlibs">
 	<title>Shared Libraries</title>