From 3e3869af11bf05dafd4dc0096672fc4f80f54ec0 Mon Sep 17 00:00:00 2001
From: Erwin Lansing <erwin@FreeBSD.org>
Date: Tue, 17 Jan 2006 18:55:31 +0000
Subject: [PATCH] Document ALWAYS_KEEP_DISTFILES which was added to comply with
 the GPLs distribution clause when using binary distfiles, which requires that
 the source code for the binary distfiles is provided as well.

Reviewed by:	simon
---
 .../books/porters-handbook/book.sgml          | 23 +++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/en_US.ISO8859-1/books/porters-handbook/book.sgml b/en_US.ISO8859-1/books/porters-handbook/book.sgml
index 3c169f11d6..b69202bde0 100644
--- a/en_US.ISO8859-1/books/porters-handbook/book.sgml
+++ b/en_US.ISO8859-1/books/porters-handbook/book.sgml
@@ -2997,6 +2997,29 @@ PATCHFILES=     patch1:test</programlisting>
 	    define in your <filename>Makefile</filename>.</para>
 	</note>
       </sect2>
+
+      <sect2>
+	<title><makevar>ALWAYS_KEEP_DISTFILES</makevar></title>
+
+	<para>If your port uses binary distfiles and has a license that
+	  requires that the source code is provided with packages distributed
+	  in binary form, e.g. GPL, <makevar>ALWAYS_KEEP_DISTFILES</makevar>
+	  will instruct the &os; build cluster to keep a copy of the files
+	  specified in <makevar>DISTFILES</makevar>.  Users of these ports
+	  will generally not need these files, so it is a good idea to only
+	  add the source distfiles to <makevar>DISTFILES</makevar> when
+	  <makevar>PACKAGE_BUILDING</makevar> is defined.
+	</para>
+
+	<example
+	  id="ports-master-sites-n-example-always-keep-distfiles">
+	  <title>Use of <makevar>ALWAYS_KEEP_DISTFILES</makevar>.</title>
+	    <programlisting>.if defined(PACKAGE_BUILDING)
+DISTFILES+=             <replaceable>foo.tar.gz</replaceable>
+ALWAYS_KEEP_DISTFILES=  yes
+.endif</programlisting>
+	</example>
+      </sect2>
     </sect1>
 
       <sect1 id="makefile-maintainer">