Trunk is now identical to Testing

git-svn-id: http://svn.linuxfromscratch.org/LFS/trunk/BOOK@4648 4aa44e1e-78dd-0310-a6d2-fbcd4c07a689

1 files changed, 24 insertions, 1 deletions

diff --git a/chapter04/aboutlfs.xml b/chapter04/aboutlfs.xml
index 2c270a08a..64f20f1b4 100644
--- a/chapter04/aboutlfs.xml
+++ b/chapter04/aboutlfs.xml
@@ -7,6 +7,29 @@
 <title>About $LFS</title>
 <?dbhtml filename="aboutlfs.html"?>
 
-<para>See testing</para>
+<para>Throughout this book, the environment variable <envar>LFS</envar> will
+be used several times. It is paramount that this variable is always defined.
+It should be set to the mount point chosen for the LFS partition.
+Check that the <envar>LFS</envar> variable is set up properly with:</para>
+
+<screen><userinput>echo $LFS</userinput></screen>
+
+<para>Make sure the output shows the path to the LFS partition's mount
+point, which is <filename class="directory">/mnt/lfs</filename> if the
+provided example was followed. If the output is incorrect, the
+variable can be set with:</para>
+
+<screen><userinput>export LFS=/mnt/lfs</userinput></screen>
+
+<para>Having this variable set is beneficial in that commands such as
+<command>mkdir $LFS/tools</command> can be typed literally. The shell
+will automatically replace <quote>$LFS</quote> with
+<quote>/mnt/lfs</quote> (or whatever the variable was set to) when it
+processes the command line.</para>
+
+<para>Do not forget to check that <envar>$LFS</envar> is set whenever
+you leave and reenter the current working environment (as when doing a
+<quote>su</quote> to <emphasis>root</emphasis> or another user).</para>
 
 </sect1>
+