Add an introduction to chapter 6 and 7

git-svn-id: http://svn.linuxfromscratch.org/LFS/branches/cross2@11910 4aa44e1e-78dd-0310-a6d2-fbcd4c07a689

1 files changed, 24 insertions, 16 deletions

diff --git a/chapter07/introduction.xml b/chapter07/introduction.xml
index 5614270b2..0445878d5 100644
--- a/chapter07/introduction.xml
+++ b/chapter07/introduction.xml
@@ -5,25 +5,33 @@
   %general-entities;
 ]>
 
-<sect1 id="ch-tools-introduction">
+<sect1 id="ch-tools-introduction-chroot">
   <?dbhtml filename="introduction.html"?>
 
   <title>Introduction</title>
 
-  <para>This chapter shows how to build a minimal Linux system.
-  This system will contain just enough tools to start constructing the final
-  LFS system in <xref linkend="chapter-building-system"/> and allow a working
-  environment with more user convenience than a minimum environment would.</para>
+  <para>This chapter shows how to build the last missing bits of the
+  temporary system: first, the tools needed by the build machinery of
+  various packages, then three packages needed to run tests.
+  Now that all circular dependencies have been resolved,
+  we can use a <quote>chroot</quote> environment, completely isolated
+  from the computer used for the build, except for the running kernel.</para>
+
+  <para>For proper operation of the isolated environment, some communication
+  with the running kernel must be established. This is done through the
+  so-called <emphasis>Virtual Kernel File Systems</emphasis>, which must be
+  mounted when entering the chroot environment. You may want to check
+  that they are mounted by issuing <command>ls $LFS/dev</command>,
+  <command>ls $LFS/proc</command>, or <command>ls $LFS/sys</command>.
+  Note that mounting the virtual kernel file systems must be done
+  <emphasis>each time you want to enter the chroot
+  environment</emphasis>.</para>
+
+  <para>Until <xref linkend="ch-tools-chroot"/>, the commands must be
+  run as <systemitem class="username">root</systemitem>, with the
+  <envar>LFS</envar> variable set. After entering chroot, all commands
+  are run as root, fortunately without access to the OS of the computer
+  you build LFS on. Be careful anyway, as it is easy to destroy the whole
+  LFS system with badly formed commands.</para>
 
-  <para>There are two steps in building this minimal system. The first step
-  is to build a new and host-independent toolchain (compiler, assembler,
-  linker, libraries, and a few useful utilities).  The second step uses this
-  toolchain to build the other essential tools.</para>
-<!--
-  <para>The files compiled in this chapter will be installed under the
-  <filename class="directory">$LFS</filename> directory to keep them
-  separate from the files installed in the next chapter and the host
-  production directories. Since the packages compiled here are temporary,
-  we do not want them to pollute the soon-to-be LFS system.</para>
--->
 </sect1>