Split Chapter 5 into three separate chapters.

Implement a new method of cross-building the LFS tool chain
and other tools to simplify the method of isolating the 
new system from the original host.  This will be the start of
LFS-10.0.

Move old trunk/BOOK to branches/old-trunk.



git-svn-id: http://svn.linuxfromscratch.org/LFS/trunk/BOOK@11946 4aa44e1e-78dd-0310-a6d2-fbcd4c07a689

1 files changed, 35 insertions, 11 deletions

diff --git a/chapter04/settingenviron.xml b/chapter04/settingenviron.xml
index 512d30d10..9c8bae7a9 100644
--- a/chapter04/settingenviron.xml
+++ b/chapter04/settingenviron.xml
@@ -43,12 +43,14 @@ umask 022
 LFS=/mnt/lfs
 LC_ALL=POSIX
 LFS_TGT=$(uname -m)-lfs-linux-gnu
-PATH=/tools/bin:/bin:/usr/bin
+PATH=/usr/bin
+if [ ! -L /bin ]; then PATH=/bin:$PATH; fi
+PATH=$LFS/tools/bin:$PATH
 export LFS LC_ALL LFS_TGT PATH</literal>
 EOF</userinput></screen>
 
   <variablelist>
-    <title>The meaning of the command line options in <filename>.bashrc</filename></title>
+    <title>The meaning of the settings in <filename>.bashrc</filename></title>
 
     <varlistentry>
       <term><parameter>set +h</parameter></term>
@@ -61,7 +63,7 @@ EOF</userinput></screen>
   be used as soon as they are installed. By switching off the hash function,
   the shell will always search the <envar>PATH</envar> when a program is to
   be run. As such, the shell will find the newly compiled tools in
-  <filename class="directory">$LFS/tools</filename> as soon as they are
+  <filename class="directory">~/tools</filename> as soon as they are
   available without remembering a previous version of the same program in a
   different location.</para>
       </listitem>
@@ -108,14 +110,36 @@ EOF</userinput></screen>
     </varlistentry>
 
     <varlistentry>
-      <term><parameter>PATH=/tools/bin:/bin:/usr/bin</parameter></term>
+      <term><parameter>PATH=/usr/bin</parameter></term>
       <listitem>
-  <para>By putting <filename class="directory">/tools/bin</filename> ahead of the
-  standard <envar>PATH</envar>, all the programs installed in <xref
-  linkend="chapter-temporary-tools"/> are picked up by the shell immediately after
-  their installation. This, combined with turning off hashing, limits the risk
-  that old programs are used from the host when the same programs are available in
-  the Chapter 5 environment.</para>
+  <para>Many modern linux distributions have merged <filename
+  class="directory">/bin</filename> and <filename
+  class="directory">/usr/bin</filename>. When this is the case, the standard
+  <envar>PATH</envar> variable needs just to be set to <filename
+  class="directory">/usr/bin/</filename> for the <xref
+  linkend="chapter-temporary-tools"/> environment. When this is not the
+  case, the following line adds <filename class="directory">/bin</filename>
+  to the path.</para>
+      </listitem>
+    </varlistentry>
+
+    <varlistentry>
+      <term><parameter>if [ ! -L /bin ]; then PATH=/bin:$PATH; fi</parameter></term>
+      <listitem>
+  <para>If <filename class="directory">/bin</filename> is not a symbolic
+  link, then it has to be added to the <envar>PATH</envar> variable.</para>
+      </listitem>
+    </varlistentry>
+
+    <varlistentry>
+      <term><parameter>PATH=$LFS/tools/bin:$PATH</parameter></term>
+      <listitem>
+  <para>By putting <filename class="directory">$LFS/tools/bin</filename> ahead of the
+  standard <envar>PATH</envar>, the cross-compiler installed at the beginning
+  of <xref linkend="chapter-cross-tools"/> is picked up by the shell
+  immediately after its installation. This, combined with turning off hashing,
+  limits the risk that the compiler from the host be used instead of the
+  cross-compiler.</para>
       </listitem>
     </varlistentry>
 
@@ -123,7 +147,7 @@ EOF</userinput></screen>
       <term><parameter>export LFS LC_ALL LFS_TGT PATH</parameter></term>
       <listitem>
         <para>While the above commands have set some variables, in order
-        to make them visible within any sub-shells, we export them</para>
+        to make them visible within any sub-shells, we export them.</para>
       </listitem>
     </varlistentry>