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<!--     eCos User Guide                                             -->
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<part ID="user-guide-introduction">
<TITLE>Introduction</TITLE>

<!--
<chapter ID="FOREWORD-WHATS-NEW">
<TITLE>What's New?</TITLE>

<para>
XXXXX So what is new??? XXXXX
</para>

</chapter>
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<!-- ==================================================== -->

<chapter ID="ecos-key-features">
<TITLE>Key Features</TITLE>

<itemizedlist>

<listitem>
<para><productname>eCos</productname> is distributed under the GPL
license with an exception which permits proprietary application code
to be linked with <productname>eCos</productname> without itself being
forced to be released under the GPL. It is also royalty and buyout
free.
</para>
</listitem>

<listitem>
<para>As an Open Source project, <productname>eCos</productname> is
under constant improvement, with an active developer community, based
around the <productname>eCos</productname> web site at <ULINK
URL="http://sources.redhat.com/ecos/">http://sources.redhat.com/ecos/</ULINK>.
</para>
</listitem>

<listitem>
<para>Powerful GUI-based configuration system allowing both large and
fine grained configuration of <productname>eCos</productname>. This
allows the functionality of <productname>eCos</productname> to be
customized to the exact requirements of the application.
</para>
</listitem>

<listitem>
<para>Full-featured, flexible, configurable, real time embedded
kernel. The kernel provides thread scheduling, synchronization,
timer, and communication primitives. It handles hardware resources
such as interrupts, exceptions, memory and caches.
</para>
</listitem>

<listitem>
<para>The Hardware Abstraction Layer (HAL) hides the specific features
of each supported CPU and platform, so that the kernel and other
run-time components can be implemented in a portable fashion.
</para>
</listitem>

<listitem>
<para>Support for &micro;ITRON and POSIX Application Programmer
Interfaces (APIs). It also includes a fully featured, thread-safe ISO
standard C library and math library.
</para>
</listitem>

<listitem>
<para>Support for a wide variety of devices including many serial
devices, ethernet controllers and FLASH memories. There is also
support for PCMCIA, USB and PCI interconnects.
</para>
</listitem>

<listitem>
<para>A fully featured TCP/IP stack implementing IP, IPv6, ICMP, UDP
and TCP over ethernet. Support for SNMP, HTTP, TFTP and FTP are also
present.
</para>
</listitem>

<listitem>
<para>The RedBoot ROM monitor is an application that uses the
<productname>eCos</productname> HAL for portability. It provides
serial and ethernet based booting and debug services during
development.
</para>
</listitem>

<listitem>
<para>Many components include test programs that validate the
components behaviour. These can be used both to check that hardware is
functioning correctly, and as examples of
<productname>eCos</productname> usage.
</para>
</listitem>

<listitem>
<para><productname>eCos</productname> documentation included this User
Guide, the Reference Manual and the Components Writer's Guide. These
are being continually updated as the system develops.
</para>
</listitem>

</itemizedlist>

</chapter>

<!-- ==================================================== -->

<chapter ID="ecos-overview">
<TITLE><productname>eCos</productname> Overview</TITLE>

<PARA><productname>eCos</productname> is an open source, configurable,
        portable, and royalty-free embedded real-time operating
        system. The following text expands on these core aspects that
        define <productname>eCos</productname>.</PARA>

<PARA><productname>eCos</productname> is provided as an open source
        runtime system supported by the GNU open source development
        tools. Developers have full and unfettered access to all
        aspects of the runtime system. No parts of it are proprietary
        or hidden, and you are at liberty to examine, add to, and
        modify the code as you deem necessary. These rights are
        granted to you and protected by the GNU Public License (GPL).
        An exception clause has been added to the eCos license which
        limits the circumstances in which the license applies to other
        code when used in conjunction with eCos. This exception grants
        you the right to freely develop and distribute applications
        based on <productname>eCos</productname>. You are not expected
        or required to make your embedded applications or any
        additional components that you develop freely available so
        long as they are not derived from
        <productname>eCos</productname> code. We of course welcome all
        contributions back to <productname>eCos</productname> such as
        board ports, device drivers and other components, as this
        helps the growth and development of
        <productname>eCos</productname>, and is of benefit to the
        entire <productname>eCos</productname> community. See <XREF
        LINKEND="ecos-licensing"> for more details.</PARA>

<PARA>One of the key technological innovations in
        <productname>eCos</productname> is the configuration
        system. The configuration system allows the application writer
        to impose their requirements on the run-time components, both
        in terms of their functionality and implementation, whereas
        traditionally the operating system has constrained the
        application's own implementation. Essentially, this enables
        <productname>eCos</productname> developers to create their own
        application-specific operating system and makes
        <productname>eCos</productname> suitable for a wide range of
        embedded uses. Configuration also ensures that the resource
        footprint of <productname>eCos</productname> is minimized as
        all unnecessary functionality and features are removed. The
        configuration system also presents
        <productname>eCos</productname> as a component
        architecture. This provides a standardized mechanism for
        component suppliers to extend the functionality of
        <productname>eCos</productname> and allows applications to be
        built from a wide set of optional configurable run-time
        components. Components can be provided from a variety of
        sources including: the standard
        <productname>eCos</productname> release; commercial third
        party developers or open source contributors.</PARA>

<PARA>The royalty-free nature of <productname>eCos</productname> means that you can develop and
deploy your application using the standard <productname>eCos</productname> release without
incurring any royalty charges. In addition, there are no up-front
license charges for the <productname>eCos</productname> runtime source code and associated
tools. We provide, without charge, everything necessary for basic
embedded applications development.</PARA>

<PARA><productname>eCos</productname> is designed to be portable to a
wide range of target architectures and target platforms including 16,
32, and 64 bit architectures, MPUs, MCUs and DSPs. The
<productname>eCos</productname> kernel, libraries and runtime
components are layered on the Hardware Abstraction Layer (HAL), and
thus will run on any target once the HAL and relevant device drivers
have been ported to the target's processor architecture and
board. Currently <productname>eCos</productname> supports a large
range of different target architectures:
 </para>

<itemizedlist>

<listitem><para>ARM, Intel StrongARM and XScale</para></listitem>

<listitem><para>Fujitsu FR-V</para></listitem>

<listitem><para>Hitachi SH2/3/4</para></listitem>

<listitem><para>Hitachi H8/300H </para></listitem>

<listitem><para>Intel x86</para></listitem>

<listitem><para>MIPS</para></listitem>

<listitem><para>Matsushita AM3x</para></listitem>

<listitem><para>Motorola PowerPC</para></listitem>

<listitem><para>Motorola 68k/Coldfire</para></listitem>

<listitem><para>NEC V850</para></listitem>

<listitem><para>Sun SPARC</para></listitem>

</itemizedlist>

<para>
including many of the popular variants of these architectures
and evaluation boards.</PARA>

<PARA><productname>eCos</productname> has been designed to support
applications with real-time requirements, providing features such as
full preemptability, minimal interrupt latencies, and all the
necessary synchronization primitives, scheduling policies, and
interrupt handling mechanisms needed for these type of
applications. <productname>eCos</productname> also provides all the
functionality required for general embedded application support
including device drivers, memory management, exception handling, C,
math libraries, etc. In addition to runtime support, the
<productname>eCos</productname> system includes all the tools
necessary to develop embedded applications, including
<productname>eCos</productname> software configuration and build
tools, and GNU based compilers, assemblers, linkers, debuggers, and
simulators.</PARA>

<PARA>To get the most out of <productname>eCos</productname> you
should visit the <productname>eCos</productname> open source
developers site: <ULINK
URL="http://sources.redhat.com/ecos/">http://sources.redhat.com/ecos/</ULINK>.
</para>

<PARA>The site is dedicated to the <productname>eCos</productname>
      developer community and contains a rich set of resources
      including news, FAQ, online documentation, installation guide,
      discussion and announcement mailing lists, and runtime and
      development tools downloads. The site also supports anonymous
      CVS and WEBCVS access to provide direct access to the latest
      <productname>eCos</productname> source base. </PARA>

<PARA><productname>eCos</productname> is released as open source
      software because we believe that this is the most effective
      software development model, and that it provides the greatest
      benefit to the embedded developer community as a whole. As part
      of this endeavor, we seek the input and participation of
      <productname>eCos</productname> developers in its continuing
      evolution. Participation can take many forms including:</PARA>
<ITEMIZEDLIST>
<LISTITEM>
<PARA>providing us with feedback on how <productname>eCos</productname> might be made more
useful to you - by taking part in the ongoing mailing list discussions
and by submitting problem reports covering bugs, documentation issues,
and missing features</PARA>
</LISTITEM>
<LISTITEM>
<PARA>contributing bug fixes and enhancement patches</PARA>
</LISTITEM>
<LISTITEM>
<PARA>contributing new code including device drivers, board
ports, libraries, and other runtime components</PARA>
</LISTITEM>
</ITEMIZEDLIST>

<PARA>Our long term aim is to make <productname>eCos</productname> a
rich and ubiquitous standard infrastructure for the development of
deeply embedded applications.  This will be achieved with the
assistance of the <productname>eCos</productname> developer community
cooperating to improve <productname>eCos</productname> for all. We
would like to take this opportunity to extend our thanks to the many
<productname>eCos</productname> developers who have already
contributed feedback, ideas, patches, and code that have augmented and
improved this release.</PARA>


<para>
<emphasis>The <productname>eCos</productname> Maintainers</emphasis>
</para>

</chapter>

<!-- ==================================================== -->

<chapter ID="ecos-licensing">
<TITLE><productname>eCos</productname> Licence Overview</TITLE>

<para>As of May 2002, <productname>eCos</productname> is released
under a modified version of the well known <ulink
url="http://www.gnu.org/copyleft/gpl.html">GNU General Public License
(GPL)</ulink>, now making it an <ulink
url="http://www.gnu.org/philosophy/license-list.html">official
GPL-compatible Free Software License</ulink>. An exception clause has
been added to the <productname>eCos</productname> license which limits
the circumstances in which the license applies to other code when used
in conjunction with <productname>eCos</productname>. The exception
clause is as follows:</para>

<programlisting width=72>
 As a special exception, if other files instantiate templates or use macros
 or inline functions from this file, or you compile this file and link it
 with other works to produce a work based on this file, this file does not
 by itself cause the resulting work to be covered by the GNU General Public
 License. However the source code for this file must still be made
 available in accordance with section (3) of the GNU General Public
 License.

 This exception does not invalidate any other reasons why a work based on
 this file might be covered by the GNU General Public License.
</programlisting>

<para>The goal of the license is to serve the
<productname>eCos</productname> user community as a whole. It allows
all <productname>eCos</productname> users to develop products without
paying anybody anything, no matter how many developers are working on
the product or how many units will be shipped. The license also
guarantees that the <productname>eCos</productname> source code will
always be freely available. This applies not only to the core
<productname>eCos</productname> code itself but also to any changes
that anybody makes to the core. In particular, it should prevent any
company or individual contributing code to the system and then later
claiming that all <productname>eCos</productname> users are now guilty
of copyright or patent infringements and have to pay royalties. It
should also prevent any company from making some small improvements,
calling the result a completely new system, and releasing this under a
new and less generous license.</para>

<para>The license does <emphasis>not</emphasis> require users to
release the source code of any <emphasis>applications</emphasis> that
are developed with <productname>eCos</productname>. However, if
anybody makes any changes to code covered by the
<productname>eCos</productname> license, or writes new files derived
in any way from <productname>eCos</productname> code, then we believe
that the entire user community should have the opportunity to benefit
from this. The license stipulates that these changes must be made
available in source code form to all recipients of binaries based on
the modified code, either by including the sources along with the
binaries you deliver (or with any device containing such binaries) or
with a written offer to supply the source code to the general public
for three years. It is perhaps most practical for
<productname>eCos</productname> developers to make the source code
available online and inform those who are receiving binaries
containing <productname>eCos</productname> code, and probably also the
<productname>eCos</productname> maintainers, about the location of the
code. See the <ulink url="http://www.gnu.org/copyleft/gpl.html">full
text of the GPL</ulink> for the most authoritative definition of the
obligations.</para>

<para>Although it is not strictly necessary to contribute the modified
code back to the <productname>eCos</productname> open source project,
we are always pleased to receive code contributions and hope that
developers will also be keen to give back in return for what they
received from the <productname>eCos</productname> project completely
free of charge.  The <productname>eCos</productname> maintainers are
responsible for deciding whether such contributions should be applied
to the public repository. In addition, a <ulink
url="http://sources.redhat.com/ecos/assign.html">copyright
assignment</ulink> is required for any significant changes to the core
<productname>eCos</productname> packages.</para>

<para>The result is a royalty-free system with minimal obligations on
the part of application developers. This has resulted in the rapid
uptake of <productname>eCos</productname>. At the same time,
<productname>eCos</productname> is fully open source with all the
benefits that implies in terms of quality and innovation. We believe
that this is a winning combination.</para>

<sect1 id="ecos-licensing-qna">
<title>Questions and answers</title>

<para>The following queries provide some clarification as to the
implications of the <productname>eCos</productname> license. They do
not consititute part of the legal meaning of the license.</para>

<para><emphasis>Q.</emphasis> What is the effect of the
<productname>eCos</productname> license?</para>

<para><emphasis>A.</emphasis> In the simplest terms, when you
distribute anything containing <productname>eCos</productname> code,
you must make the source code to <productname>eCos</productname>
available under the terms of the GPL.</para>

<para><emphasis>Q.</emphasis> What if I make changes to
<productname>eCos</productname>, or write new code based on
<productname>eCos</productname> code?</para>

<para><emphasis>A.</emphasis> Then you must make those changes
available as well.</para>

<para><emphasis>Q.</emphasis> Do I have to distribute the source
code to my application? Isn't the GPL "viral"?</para>

<para><emphasis>A.</emphasis> You do not have to distribute any
code under the terms of the GPL other than
<productname>eCos</productname> code or code derived from
<productname>eCos</productname>. For example, if you write a HAL port
based on copying an existing <productname>eCos</productname> HAL in
any way, you must make the source code available with the
binary. However you would not need to make available any other code,
such as the code of a wholly separate application linked with
<productname>eCos</productname>.</para>

<para><emphasis>Q.</emphasis> I would rather stick with the
RHEPL code, but I updated my anonymous CVS checkout.</para>

<para><emphasis>A.</emphasis> You can check out the final
version of anonymous CVS before the license change using the CVS tag
<literal>last-rhepl</literal>. See <ulink
url="http://sources.redhat.com/ecos/anoncvs.html">the anonymous CVS
access page</ulink>
for details.</para>

</sect1>

<sect1 id="ecos-licensing-previous">
<title>Previous License</title>

<para>

Prior to May 2002, <productname>eCos</productname> was released under
the <ulink url="http://sources.redhat.com/ecos/old-license.html">Red
Hat eCos Public License (RHEPL)</ulink>. The RHEPL required any
modifications to <productname>eCos</productname> code to be made
available under preferential terms to Red Hat and was therefore
incompatible with code licensed under the GPL.  The use of
<productname>eCos</productname> source code which was licensed under
the RHEPL is not affected by the switch to the modified GPL for later
revisions.
</para>

</sect1>

</chapter>

<!-- ==================================================== -->

<chapter id="notation-and-conventions">
<title>Notation and Conventions</title>

<para>
Since there are many supported target architectures, notation
conventions are used in this manual to avoid repeating instructions
that are very similar.
</para>

<SECT1 ID="GDB-AND-GCC-COMMAND-NOTATION"><!-- <index></index> --><!-- <xref> -->
<TITLE>GDB and <!-- <index></index> -->GCC Command Notation</TITLE>

<para>
Cross-development commands like <COMMAND>gcc</COMMAND> and
<COMMAND>gdb</COMMAND> will be shown with a
<replaceable>TARGET-</replaceable> prefix. You need to replace
<replaceable>TARGET-</replaceable> with the correct prefix before
using the command. Just using <command>gcc</command> or
<command>gdb</command> will use the tools for the host, which is not
(usually) what you want.
</para>

<para>
For example use <command>arm-elf-gcc</command> and
<command>arm-elf-gdb</command> for ARM, Thumb, and StrongARM targets.
Use <command>xscale-elf-gcc</command> and
<command>xscale-elf-gdb</command> for Intel Xscale targets.
Use <command>i386-elf-gcc</command> and
<command>i386-elf-gdb</command> for IA32 targets. And so on, the exact
prefix to use is shown in the documentation for each target.
</para>

<PARA>Note that some versions of the GCC cross compiler generate
executable files with the <FILENAME>.exe</FILENAME> suffix on Windows,
but not on Linux. The suffix <FILENAME>.exe</FILENAME> will be omitted
from executable file names, so you will see <FILENAME>hello</FILENAME>
instead of <FILENAME>hello.exe</FILENAME>.</PARA>

</sect1>

<SECT1 ID="DIRECTORY-AND-FILE-SYSTEM-CONVENTIONS"><!-- <index></index> -->
<TITLE>Directory and File System Conventions</TITLE>

<PARA>The default directory for installing
<productname>eCos</productname> on Windows (usually
<FILENAME>C:/Program Files/eCos</FILENAME>) is different from that on
Linux (usually <FILENAME>/opt/ecos</FILENAME>).  Since many command
line examples in the tutorials use these paths, this default (base)
directory will be cited as <replaceable>BASE_DIR</replaceable>.</PARA>

<PARA>Windows and Linux have a similar file system syntax, but the
MS-DOS command interpreter on Windows uses the backslash character
(\) as a path separator, while Linux and POSIX shells (including
the Cygwin bash shell for windows) use the forward slash (/).</PARA>

<PARA>This document will use the POSIX shell convention of forward
slashes throughout.</PARA>

</SECT1>

<!-- ==================================================== -->

<SECT1 ID="VERSION-CONVENTIONS">
<TITLE>Version Conventions</TITLE>

<para>
This manual does not refer explicitly to any particular version of
<productname>eCos</productname>. However, version numbers form part of
many file path names. In all of these places the version number will
be shown like this: <replaceable>&Version;</replaceable>.
</para>

<para>
If you have used anonymous CVS to check
<productname>eCos</productname> out of the CVS repository, the version
number will always be <literal>current</literal>, since that is the
name of the directory in the repository. When a stable release is made
this directory name is changed, in the release, to the number of the
release, for example <literal>v2_0</literal> or
<literal>v2_1</literal>.
</para>

</SECT1>


</chapter>



<chapter id="documentation-roadmap">
<title>Documentation Roadmap</title>

<para>
The <productname>eCos</productname> documentation is divided into a
three main parts:
</para>

<VARIABLELIST>
<VARLISTENTRY>
<TERM><EMPHASIS>User Guide</EMPHASIS></TERM>
<LISTITEM>
<PARA>This document. It includes the following sections:</PARA>

  <VARIABLELIST>
  <VARLISTENTRY>
  <TERM>Installing <productname>eCos</productname></TERM>
  <LISTITEM>
  <para>
  This section describes how to install the
  <productname>eCos</productname> software, how to set up your
  hardware and how to test that it is all working.
  </para>
  </listitem>
  </varlistentry>

  <VARLISTENTRY>
  <TERM>Programming Under <productname>eCos</productname></TERM>
  <LISTITEM>
  <para>
  This section describes how to write programs that run under
  <productname>eCos</productname> by running through some examples.
  </para>
  </listitem>
  </varlistentry>

  <VARLISTENTRY>
  <TERM>The <productname>eCos</productname> <application>Configuration Tool</application></TERM>
  <LISTITEM>
  <para>
  This section describes the <productname>eCos</productname> graphical
  configuration tool and how to use it to change how
  <productname>eCos</productname> behaves.</para>
  </listitem>
  </varlistentry>

  <VARLISTENTRY>
  <TERM><productname>eCos</productname> Programming Concepts and Techniques</TERM>
  <LISTITEM>
  <PARA>An explanation of the <productname>eCos</productname> programming
            cycle, and a description of some debugging facilities that
            <productname>eCos</productname> offers.
  </PARA>
  </listitem>
  </varlistentry>

  <VARLISTENTRY>
  <TERM>Configuration and the Package
              Repository</TERM>
  <LISTITEM>
  <PARA>Information on how to configure <productname>eCos</productname>
              manually, including a reference on the
              <command>ecosconfig</command> command, memory layouts,
              and information on how to manage a package repository
              using the <productname>eCos</productname> Package Administration
              Tool.
            </PARA>
  </LISTITEM>
  </VARLISTENTRY>


  </variablelist>

</LISTITEM>
</VARLISTENTRY>

<VARLISTENTRY>
<TERM><EMPHASIS>Reference Guide</EMPHASIS></TERM>
<LISTITEM>

<PARA>The Reference Guide provides detailed documentation on various
aspects of <productname>eCos</productname>. This document is being
constantly updated, so the following list just mentions the more
important sections, take a look at the guide itself for the full
story.</PARA>

  <variablelist>

  <VARLISTENTRY>
  <TERM>The <productname>eCos</productname> Kernel</TERM>
  <LISTITEM>
  <PARA>In-depth description of <productname>eCos</productname>&quot;s
              native C kernel API Important considerations are given
              for programming the <productname>eCos</productname>
              kernel. The semantics for each kernel function are
              described, including how they are affected by
              configuration. </PARA>
  </LISTITEM>
  </VARLISTENTRY>

  <VARLISTENTRY>
  <TERM>POSIX and &micro;ITRON APIs</TERM>
  <LISTITEM>
  <PARA>A description of the POSIX and &micro;ITRON APIs and how they
  are supported under <productname>eCos</productname>.
  </para>
  </LISTITEM>
  </VARLISTENTRY>

  <VARLISTENTRY>
  <TERM>The <productname>eCos</productname> Hardware Abstraction Layer (HAL)</TERM>
  <LISTITEM>
  <PARA>A description of the structure and functionality of the
  <productname>eCos</productname> HAL. This section also includes a
  porting guide to help moving <productname>eCos</productname> to
  different platforms.
  </para>
  </LISTITEM>
  </VARLISTENTRY>

  <VARLISTENTRY>
  <TERM>Device Drivers</TERM>
  <LISTITEM>
  <PARA>A description of the philosophy behind
              <productname>eCos</productname> device drivers, as well as a
              presentation of the C language APIs for using the current
              device drivers. </PARA>
  <para>
    Device driver support includes serial, ethernet and FLASH devices,
    and support for PCI, PCMCIA and USB interconnects.
  </para>
  </LISTITEM>
  </VARLISTENTRY>

  <VARLISTENTRY>
  <TERM>RedBoot User's Guide</TERM>
  <LISTITEM>
  <PARA>This describes RedBoot, which provides a complete bootstrap
        environment for a range of embedded operating systems, such as
        embedded Linux and <productname>eCos</productname>, and
        includes facilities such as network downloading and
        debugging. It also provides a simple flash file system for
        boot images.
  </para>
  </LISTITEM>
  </VARLISTENTRY>

  <VARLISTENTRY>
  <TERM>TCP/IP Stack Support</TERM>
  <LISTITEM>
  <PARA>This describes the Common Networking for
        <productname>eCos</productname> package, which provides
        support for a complete TCP/IP networking stack. The design
        allows for the actual stack to be modular and at the current
        time two different implementations, one based on OpenBSD from
        2000 and a new version based on FreeBSD, are available.
  </para>
  <para>Other components related to networking, including support for
        SNMP, DNS, HTTP and FTP, are also described.
  </para>
  </LISTITEM>
  </VARLISTENTRY>

  </variablelist>

</LISTITEM>
</VARLISTENTRY>

<VARLISTENTRY>
<TERM><EMPHASIS>Component Writer's Guide</EMPHASIS></TERM>
<LISTITEM>
<PARA>The Component Writer's Guide is intended for developers who need
to add or modify parts of <productname>eCos</productname> itself. It
describes the following things:
</PARA>

  <VARIABLELIST>
  <VARLISTENTRY>
  <TERM>Overview</TERM>
  <LISTITEM>
  <PARA>An explanation of the configuration technology used in
  <productname>eCos</productname>, why it is done this way, how it
  works and the terminology used.
  </para>
  </LISTITEM>
  </VARLISTENTRY>

  <VARLISTENTRY>
  <TERM>Package Organization</TERM>
  <LISTITEM>
  <PARA>A description of the <productname>eCos</productname> package
  repository, how it is organized and how packages themselves are
  organized.
  </para>
  </LISTITEM>
  </VARLISTENTRY>

  <VARLISTENTRY>
  <TERM>The CDL Language</TERM>
  <LISTITEM>
  <PARA>A description of the CDL language and how it is used to
  control the configuration of <productname>eCos</productname>
  components. The document also contains a complete specification of
  the language.
  </para>
  </LISTITEM>
  </VARLISTENTRY>

  <VARLISTENTRY>
  <TERM>The Build Process</TERM>
  <LISTITEM>
  <PARA>A description of what happens once a configuration has been
  created and must be built into a set of executables.
  </para>
  </LISTITEM>
  </VARLISTENTRY>

  </variablelist>

</LISTITEM>
</VARLISTENTRY>
</variablelist>

</chapter>


</part>