path: root/web/mono-beginning.xml

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<!DOCTYPE article PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN" []>
<article>

  <articleinfo>

    <!-- Use "HOWTO", "mini HOWTO", "FAQ" in title, if appropriate -->
    <title>Running Mono</title>


    <author>
       <firstname>Hinne</firstname>
       <surname>Hettema</surname>
       <affiliation>
          <address><email>h.hettema@auckland.ac.nz</email></address>
       </affiliation>
     </author>
    <author>
       <firstname>Jaime</firstname>
       <surname>Anguiano Olarra</surname>
       <affiliation>
          <address><email>jaime@genuara.ugr.es</email></address>
       </affiliation>
     </author>

     <pubdate>2002-06</pubdate>

     <!-- Most recent revision goes at the top; list in descending order -->
     <!-- All dates specified in ISO "YYYY-MM-DD" format -->
     <revhistory>
       <revision>
          <revnumber>0.1</revnumber>
          <date>2002-06-20</date>
          <authorinitials>HH</authorinitials>
          <revremark>First release</revremark>
       </revision>
     </revhistory>

     <!-- Provide a good abstract; a couple of sentences is sufficient -->
     <abstract>
        <para>
	This document describes how to install mono on your Linux system 
	from the source and describes some simple experiments you can
	perform with this installation.
	</para>
     </abstract>

  </articleinfo>


<sect1 id="intro">
<title>Introduction</title>

<para>
Mono is an open source implementation of the Common Language Infrastructure
(CLI) specified in ECMA standard 335. It comes with a C# compiler and
provides an extensible platform to develop and run applications that
are interoperable with Microsoft .NET.
</para>

<para>
Mono is not finished--it is a project still under development. As a
result, installation and configuration may not be as smooth as you
will be used to from other Linux applications. Nevertheless, mono is
in a state that will allow you to get it up and running and gain
experience with it--which is, I would suggest, a very smart thing to do.
</para>

<para>
This document is limited in the following sense: it describes how to
download a 'stable' version of mono as a 'tarball' and get it to run on
your computer. I'm also assuming you run mono on Linux rather than
on Windows. All the examples have been tested on a 'vanilla' Red Hat 7.3 
installation.
</para>

<para>
There are two items this document will <emphasis>not 
</emphasis> cover: the first is how to self host the mcs compiler 
under linux and the second is the graphical user environment 
which is implemented as GTK#. These two interesting topics 
are the subject of two more howto's that I'm planning.
</para>

<para>
This document is also less useful for two types of people.
</para> 
<itemizedlist> 
<listitem> 
<para> 
If you are a very inexperienced linux user and want to know what mono is
all about, there is an easier way to install mono. Go to mono.baselabs.org
and download the rpm's ready for installation on your system. This site also
runs a tutorial that is worth reading.
</para> 
</listitem> 
<listitem> 
<para> 
If you are a very experienced user wanting to contribute to the mono code,
you should probably regularly do a CVS download. At the moment, the mono
code grows very fast, and the 'stable' releases still appear too slowly.
</para>
</listitem>

</itemizedlist>

<para>
This document is aimed at the mono beginner, and aims to present a complete
view of a minimal installation, which will allow you to experiment with
mono to some degree. It also describes some of those experiments. We
expect that after reading this document you'll go on to do either of
two things:
</para>
<orderedlist>
<listitem>
<para>
Continue to contribute to the mono project in some shape or form. The
website has some ideas and suggestions under the heading 'Contributing'.
</para>
</listitem>
<listitem>
<para>
Continue to write applications that run in mono. 
</para>
</listitem>
</orderedlist>

<para>
We hope this document will be useful to you in your first steps with mono.
Happy hacking!
</para>

<sect2 id="note">
<title>A note on the development of this document</title>
<para>
This document is expected to grow into a full 'running mono howto' over time.
As of yet, it does not really discuss some of the excellent efforts of others
to package mono into an rpm or deb and prepare it for easy installation.
It is our aim to include this in future versions of this document.
</para>
</sect2>

<sect2 id="prerequisites">
<title>Prerequisites</title>
<para>
This document assumes you are somewhat familiar with the architecture
of the Common Language Infrastructure and the C# programming language.
</para>

<para>
To compile mono on your system, you will also have to satisfy 
some dependencies on other software. A list of these are given 
on the mono download page. Read through this list to see if 
you've got all components. 
</para>

<para>
On a practical note, I had no dependency issues with the 
installation of mono 0.12 on a 'standard issue' Red Hat 7.3 build.
</para>

</sect2>

<sect2 id="disclaimer"> <title>Disclaimer</title>

<para> 
No liability for the contents of this document can be accepted.
Use the concepts, examples and information at your own risk.  There may
be errors and inaccuracies, that could be damaging to your system.
Proceed with caution, and although this is highly unlikely, the author(s)
do not take any responsibility.  
</para>

<para> 
All copyrights are held by their by their respective owners,
unless specifically noted otherwise.  Use of a term in this document
should not be regarded as affecting the validity of any trademark or
service mark.  Naming of particular products or brands should not be
seen as endorsements.  
</para> 
</sect2>

<!-- Give credit where credit is due...very important --> <sect2
id="credits"> <title>Credits / Contributors</title>

<para> This document was originally created by Jaime Anguiano Olarra,
but has been extensively rewritten. Credits are due to </para>
<itemizedlist> 
<listitem> 
<para>Jaime Anguiano Olarra <email>jaime@geneura.ugr.es</email> 
for creating the original version of this document, and in fact 
the document that got me through installing mono for the first time.
</para> 
</listitem> 
<listitem>
<para>
My partner Margaret for support on my more exotic ventures.
</para>
</listitem>
</itemizedlist> 
</sect2>

<!-- Feedback --> 
<sect2 id="feedback"> <title>Feedback</title>

<para> 
Feedback is most certainly welcome for this document. Send your
additions, comments and criticisms to the following email address:
<email>mono-docs-list@ximian.com</email>. I am lurking on this list 
and will maintain this document as required.  
</para> 
</sect2>
</sect1>

<!-- This is the preamble stuff over with the rest of document
follows... --> 
<sect1 id="installation"> 
<title> Installing Mono</title>

<sect2 id="obtaining"> 
<title>Obtaining Mono</title> 
<para> 
There are several ways to get Mono running on your computer. This
document will discuss only one of those: downloading the source tarball
and utilising the make utilities to get mono up and running.  There is
only one mono package to worry about if you are just after a 'base' install
of mono: the mono runtime. This package, found under the name "mono-x.xx"
has got a compiled version of the compiler built in.
</para>

<para>
You'll be able to complete everything in this document if you just install
the runtime, but taking a look at the compiler package is well worth the
effort. The compiler is written in C# and is 'self hosting' which means it
is able to compile itself. 
</para>

<para>
As of this moment, it is my understanding that there are still some issues
with the 'self hosting' bit of the compiler on linux, although this is 
expected to work in later versions of mono. If you are just interested in
finding out how mono will work under linux, I would not worry about the
self-hosting bit for now. The self-hosting of the compiler will be the
topic of a future howto.
</para>

<para> 
See <ulink url="http://www.go-mono.com/download">the mono download
site</ulink> for the source of the tarballs.  
</para>

<para>
This page also lists the current versions of the software 
mono depends on. Make sure that your system has all the 
required versions, otherwise mono won't compile.
</para>

<para>
At a minimum for mono 0.12, you'll need to:
</para>

<itemizedlist>
<listitem>
<para>
download and install
<ulink url="http//www.freedesktop.org/software/pkgconfig">
pkg-config</ulink>.
</para>
</listitem>
<listitem>
<para>
download and install
<ulink url="ftp://ftp.gtk.org/pub/gtk/v1.3/glib-1.3.12.tar.gz">
glib 1.3</ulink>.
</para>
</listitem>
</itemizedlist>

<para> 
Installing the tarballs is done via GNU autoconf and
automake. The general upshot of running autoconf and automake is that you
can type <command>./configure</command> and then <command> make</command>
to do the build.  
Typing <command>make install</command> completes the installation of mono
on your system.
</para>

<para>
To build the mono runtime package, unzip the tarball to some useful
location.  I tend to use <command>/usr/src</command> as the location,
but you could really do it anywhere. For the install process, it is
also a good idea to be 'root'.  The installation process will shuttle
some executables into <command>/usr/local/bin</command> (more about
that later).
</para>

<para>
Unzipping the tarballs will have created two directories in <command>
/usr/src/</command>, one called something like mono-x.xx and the other 
mcs-x.xx. The one called 'mono' is the runtime environment, and this contains
all that is initially needed to run mono and investigate its inner workings.
</para>

<para>
To start building the mono runtime, first type <command>./configure</command>.
You will see an output like this:
</para>
<programlisting>
[root@taurus mono-0.12]# ./configure
loading cache ./config.cache
checking host system type... i686-pc-linux-gnu
checking target system type... i686-pc-linux-gnu
checking build system type... i686-pc-linux-gnu
checking for a BSD compatible install... (cached) /usr/bin/install -c
checking whether build environment is sane... yes
checking whether make sets ${MAKE}... (cached) yes
checking for working aclocal... found


snip ....


checking BASE_DEPENDENCIES_CFLAGS...  -I/usr/include/glib-2.0 -I/usr/lib/glib-2.0/include
checking BASE_DEPENDENCIES_LIBS...  -lglib-2.0
checking for GC_malloc in -lgc... (cached) no
configure: warning: Compiling mono without GC.
checking if off_t is 64 bits wide... no
checking if _FILE_OFFSET_BITS=64 gives 64 bit off_t... ok

snip ...

creating Makefile
creating mono/Makefile
creating mono/utils/Makefile
creating mono/metadata/Makefile
creating mono/dis/Makefile
creating mono/cil/Makefile
creating mono/arch/Makefile
creating mono/os/Makefile
creating mono/os/win32/Makefile
creating mono/os/unix/Makefile
creating mono/arch/x86/Makefile
creating mono/arch/ppc/Makefile
creating mono/arch/sparc/Makefile
creating mono/arch/arm/Makefile
creating mono/interpreter/Makefile
creating mono/tests/Makefile
creating mono/benchmark/Makefile
creating mono/monoburg/Makefile
creating mono/monograph/Makefile
creating mono/jit/Makefile
creating mono/io-layer/Makefile
creating mono/handles/Makefile
creating runtime/Makefile
creating scripts/Makefile
creating man/Makefile
creating doc/Makefile
creating docs/Makefile
creating config.h
config.h is unchanged


        GC:     auto


[root@taurus mono-0.12]#
</programlisting>


<para>
This means that the configure script has now created all the 
makefiles necessary to complete the build on your system. 
Note the "GC: auto" at the end of the list of commands. 
GC stands for "garbage collection" and it
will be addressed in a later section of this document.
</para>
<para>
You are now ready to start the mono "build" process. To kick 
this off, you can type <command>make</command> at the 
command prompt. You'll see something like this:
</para>

<programlisting>
[root@taurus mono-0.12]# make
make  all-recursive
make[1]: Entering directory `/usr/src/mono-0.12'
Making all in mono
make[2]: Entering directory `/usr/src/mono-0.12/mono'
Making all in utils
make[3]: Entering directory `/usr/src/mono-0.12/mono/utils'
gcc -DHAVE_CONFIG_H -I. -I. -I../.. -I/usr/include/glib-2.0 
-I/usr/lib/glib-2.0/include   -I/usr/include/glib-2.0 
-I/usr/lib/glib-2.0/include   -I../.. -I../../mono   
-D_FILE_OFFSET_BITS=64 -D_GNU_SOURCE   -g -Wall 
-Wunused -Wmissing-prototypes -Wmissing-declarations 
-Wstrict-prototypes  -Wmissing-prototypes -Wnested-externs 
-Wpointer-arith -Wno-cast-qual -Wcast-align -Wwrite-strings 
-c mono-hash.c

</programlisting>
<para>
and this will continue for a while. On my 1 GHz Duron with 256 MB of RAM the 
total build process takes about three minutes. All the terrible flags after gcc
have essentially been set by the configure script and there is no need to worry
about these.
</para>
<para>
To finally install mono, you can type <command>make install</command> 
to get a working version of mono. This command will copy the 
scripts that run the executables to a place where the operating system
will be ale to find them. This location is <command>/usr/local/bin</command>
on my system. 
</para>

</sect2>

<sect2 id="garbage_collection">
<title> Garbage Collection</title>
<para>
To make the mint interpreter work with garbage collection, you first need to
install a garbage collection package on your system. Mono works with
Boehm Garbage collection, which is found at 
<ulink url="http://www.hpl.hp.com/personal/Hans_Boehm/gc/">
http://www.hpl.hp.com/personal/Hans_Boehm/gc/
</ulink>.
</para>

<para>
To get garbage collection to work, I downloaded the source tarball 
into <command>/usr/src/</command> and typed <command>./configure</command>
followed by <command>make</command> and <command>make install</command>.
</para>

<para>
There is one glitch to work around. The header file for the garbage collection
<command>gc.h</command> is found in the <command>/usr/src/gc6.0/include
</command> directory (at least on my system). The mono build process will break
on this location: it is looking for the header file in some other place called
<command>/usr/include/gc/</command> and won't be able to find the correct
header file.
</para>

<para>
The solution is to build a symbolic link between these two locations as 
follows
</para>

<programlisting>
[root@taurus include]# ln -s /usr/src/gc6.0/include/ /usr/include/gc
</programlisting>

<para>
after which you'll be able to list the directory contents as if they were
in <command>/usr/include</command>
</para>

<programlisting>
[root@taurus include]# pwd
/usr/include
[root@taurus include]# ls /usr/include/gc
cord.h                gc_backptr.h  gc_inline.h             javaxfc.h
ec.h                  gc_cpp.h      gc_local_alloc.h        leak_detector.h
gc                    gc_gcj.h      gc_mark.h               new_gc_alloc.h
gc_alloc.h            gc.h          gc_pthread_redirects.h  private
gc_amiga_redirects.h  gc_inl.h      gc_typed.h              weakpointer.h
[root@taurus include]#
</programlisting>

<para>
To get mono to work with garbage collection, you'll have to rebuild the
environment. This is done easily by typing <command>make distclean</command>
to clean up any existing executables.
</para>

<para>
Continue the build by typing <command>./configure</command>, and look at
the last line. It should read:
</para>

<programlisting>

snip...

creating config.h


        GC:     boehm


[root@taurus mono-0.12]#

</programlisting>

<para>
The GC: boehm tells you that garbage collection has been turned on. Now to
compile the runtime, you type <command>make</command> and <command> make
install</command> as previously.
</para>

<para>
You now have mono working with Garbage Collection.
</para>

<para>
Although my experimentation is incomplete as of this time, I have found some
issues with running Garbage Collection continuously, and my recommendation
would be to turn it off for now.
</para>

<para>
To turn garbage collection off again, you have to go to the <command>/usr/src
</command> directory where you extracted the tarball. Enter the <command>gc6.0
</command> directory and type <command>make uninstall</command> to uninstall 
Garbage Collection. Then in your <command>mono</command> directory, type
<command>make distclean</command> followed by <command>./configure</command>,
<command>make</command> and <command>make install</command>.
</para>

</sect2>

</sect1>

<sect1 id="running">
<title>Running mono</title>
<sect2 id="basic">
<title>Basic steps</title>
<para>
To work with mono, you first have to create a C# program. Open up 
your favourite editor, and type in the following code:
</para>
<programlisting>
using System;

class Hello
{
public static void Main(String[] args)
	{
	Console.WriteLine("mono:: is alive and well...");

	for (int i = 0; i < args.Length; i++)
		Console.WriteLine("Argument {0} = {1}", i, args[i]);
	}
}
</programlisting>

<para>
Save the file as hello.cs. To compile this into a working program, 
type mcs hello.cs. If you get the following:
</para>
<programlisting>
[hinne@taurus hello]$ mcs hello.cs
RESULT: 0
[hinne@taurus hello]$
</programlisting>
<para>
you know the compile worked fine. If you see some strange error
messages including the word 'parser' somewhere, you made a mistake in
your program. Fix this up first.
</para>

<para>
You are now ready to execute your first mono program.  To execute 
the code, type
</para>

<programlisting>
[hinne@taurus hello]$ mono hello.exe arg1 arg2 arg 3
</programlisting>
<para>
(where we have given some arguments just for fun) and you'll 
see the following:
</para>

<programlisting>
mono:: is alive and well...
Argument 0 = arg1
Argument 1 = arg2
Argument 2 = arg
Argument 3 = 3
RESULT: 0
</programlisting>
<para>
As you can see, mono printed the line "mono:: is alive and well" 
and printed the list of arguments. This completes the creation 
and execution of your first mono program.
</para>
</sect2>

<sect2 id="interpreter">
<title>Interpreter</title>
<para>
But mono will allow you to do more. First of all, mono is the 
compiled mono execution environment which uses the Just in 
Time (JIT) compiler. Mono also comes with an interpreted 
environment, which can be accessed using the command 'mint' 
as follows
</para>
<programlisting>
[hinne@taurus hello]$ mint hello.exe arg1 arg 2
mono:: is alive and well...
Argument 0 = arg1
Argument 1 = arg
Argument 2 = 2
[hinne@taurus hello]$
</programlisting>
<para>
As you can see, it makes no difference to mono output which 
environment you use, but what happens under the hood is very 
different. If you use 'mono' as the command line tool, you 
call the 'production' execution environment which will read 
your portable executable (PE) file, and call the just in 
time (JIT) compiler to compile the PE code down to machine 
level code (in my case, an x86 architecture) after which 
it is executed.
</para>
<para>
If you use mint, the JIT is not used, and the PE code is 
interpreted into x86 instructions for execution. In fact, 
for our simple 'hello' mint is slightly faster. The point 
is that the JIT compiler will take some time to compile the 
code of our program and store it in some location in memory, 
but the subsequent execution of the code is faster with mono.
</para>
<para>

You can see what happens below (the thing to look for is the 
'user' time: 0.1 seconds with mono and 0.06 seconds with mint):

</para>
<programlisting>
[hinne@taurus hello]$ time mono hello.exe arg1 arg 2
mono:: is alive and well...
Argument 0 = arg1
Argument 1 = arg
Argument 2 = 2
RESULT: 0

real    0m0.575s
user    0m0.100s
sys     0m0.010s
[hinne@taurus hello]$ time mint hello.exe arg1 arg 2
mono:: is alive and well...
Argument 0 = arg1
Argument 1 = arg
Argument 2 = 2

real    0m0.545s
user    0m0.060s
sys     0m0.000s
[hinne@taurus hello]$
</programlisting>
<para>
After this simple run of mono, it is time to play with some options. 
I won't cover these in detail since there are quite a few, and also because
I assume you downloaded mono to hack it around in the first place. So
I'll leave some pointers.
</para>


<sect3 id="debugging">
<title>Debugging</title>
<para>
Mono supports a debugging option when you specify the "-d" flag while running
the runtime. Utilising this flag will get you a significant amount of output,
and it may be an idea to specify an output file as well. The interesting aspect
of this file is that it allows you to see to some extent (quite precisely,
actually) what the JIT compiler is up to.
</para>
</sect3>

<sect3 id="statistics">
<title>Statistics</title>
<para>
It is also possible to collect some runtime statistics on your program. These
will give you some idea of the resource utilisation of your program.
</para>
<programlisting>
[hinne@taurus hello]$ mono --stats hello.exe
mono:: is alive and well...
RESULT: 0
Mono Jit statistics
Compiled methods:       58
Methods cache lookup:   15
Method trampolines:     698
Basic blocks:           188
Max basic blocks:       15
Allocated vars:         238
Analyze stack repeat:   61
Compiled CIL code size: 2450
Native code size:       10167
Max code size ratio:    7.13 (FileStream::FlushBuffer)
Biggest method:         1016 (StreamWriter::Write)
Code reallocs:          27
Allocated code size:    22073
Inlineable methods:     17
Inlined methods:        22

Created object count:   18
Initialized classes:    127
Used classes:           37
Static data size:       288
VTable data size:       8292
</programlisting>
</sect3>

</sect2>

<sect2 id="ILAsm_code" >
<title>Inspecting IL Assembly code</title>
<para>
Mono also provides a small tool that will let you disassemble 
the executable (.exe) file so you can have a peek 
under the hood. This tool is monodis, and is run as 
follows:

</para>
<programlisting>
[hinne@taurus hello]$ monodis hello.exe
.assembly extern mscorlib
{
  .ver 0:0:0:0
}
.assembly 'hello'
{
  .hash algorithm 0x00008004
  .ver  0:0:0:0
}
  .class private auto ansi beforefieldinit Hello
        extends [mscorlib]System.Object
  {

    // method line 1
    .method public hidebysig  specialname  rtspecialname
           instance default void .ctor()  cil managed
    {
        // Method begins at RVA 0x20ec
        // Code size 7 (0x7)
        .maxstack 8
        IL_0000: ldarg.0
        IL_0001: call instance void System.Object::.ctor()
        IL_0006: ret
    } // end of method instance default void .ctor()

    // method line 2
    .method public static
           default void Main(string[] args)  cil managed
    {
        // Method begins at RVA 0x20f4
        .entrypoint
        // Code size 56 (0x38)
        .maxstack 5
        .locals init (
                int32   V_0,
                int32   V_1)
        IL_0000: ldstr "mono:: is alive and well..."
        IL_0005: call void System.Console::WriteLine(string)
        IL_000a: ldc.i4.0
        IL_000b: stloc.0
        IL_000c: ldloc.0
        IL_000d: ldarg.s 0
        IL_000f: ldlen
        IL_0010: clt
        IL_0012: brfalse IL_0037

        IL_0017: ldstr "Argument {0} = {1}"
        IL_001c: ldloc.0
        IL_001d: box [mscorlib]System.Int32
        IL_0022: ldarg.s 0
        IL_0024: ldloc.0
        IL_0025: ldelem.ref
        IL_0026: call void System.Console::WriteLine(string, object, object)
        IL_002b: nop
        IL_002c: ldloc.0
        IL_002d: ldc.i4.1
        IL_002e: add
        IL_002f: stloc.1
        IL_0030: ldloc.1
        IL_0031: stloc.0
        IL_0032: br IL_000c

        IL_0037: ret
    } // end of method default void Main(string[] args)

  } // end of type Hello

[hinne@taurus hello]$
</programlisting>
<para>
This is the listing of the code of your program in a language 
called IL assembly, or Common Intermediate Language (CIL). The 
CIL provides the portability of the mono platform, and ensures 
that code compiled with Microsoft's .NET framework will work 
on mono and vice versa. 
</para>
</sect2>

<sect2 id="man_pages">
<title>Man pages</title>

<para>
Mono has man pages already installed, and generally, typing <command>
man</command> before the command you wish to execute should help in 
getting a list of the options. In many cases, it's still up to you
to figure out what they do.
</para>

</sect2>


</sect1>


<sect1 id="problems">
<title>Problems</title>
<para> 
With mono being as new as it is, it is likely that you will have some
problems with installation. The following are some ideas to help you
out in a bind:
</para>

<orderedlist>
<listitem>
<para> 
See the Ximian Bugzilla page to find out if there is a bug
report about your specific issue.
</para>
</listitem>

<listitem>
<para>Read this document.  If it does not solve your problem, we want to
know about it. Please send a message to the email address listed for
feedback at the beginning of the document.</para>
</listitem>

<listitem>

<para> 
Visit the mono mailing lists' archives and do a little
research in there for threads talking about the problem you have.
</para>
</listitem>

<listitem>
<para> 
If you still cannot correct the problem, send a message to the
mono list. When you do this, please be as precise as possible--i.e.
mention the system you are running, the version of mono that you have the 
problem with, and give any error codes and other output that might appear.
</para>
</listitem>
</orderedlist>

</sect1>

<sect1 id="knownproblems">
<title>Known Problems</title>

<para> mcs fails to compile in Linux.
To the best of my knowledge, as of yet mcs cannot compile in Linux. 
Try to install the already made packages from 
http://mono.baselabs.org/index.php/software. </para>
</sect1>

<!-- Legal Sections --> <sect1 id="copyright">
 <title>Copyright and License</title>

 <!-- The LDP recommends, but doesn't require, the GFDL --> <para>
     This document, <emphasis>Running mono</emphasis>, is copyrighted
     (c) 2002 by <emphasis>Hinne Hettema</emphasis> and
     <emphasis>Jaime Anguiano Olarra</emphasis>.  Permission is
     granted to copy, distribute and/or modify this document under the
     terms of the GNU Free Documentation License, Version 1.1 or any later
     version published by the Free Software Foundation; with no Invariant
     Sections, with no Front-Cover Texts, and with no Back-Cover Texts.
     A copy of the license is included in the section entitled "GNU Free
     Documentation License".
 </para>

<sect2 id="gfdl"> <title>GNU Free Documentation License</title> 
<!-- GNU Project - Free Software Foundation (FSF) -->

<para>Version 1.1, March 2000</para>

<blockquote> <para>Copyright (C) 2000  Free Software Foundation, Inc.
59 Temple Place, Suite 330, Boston, MA	02111-1307  USA Everyone is
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but changing it is not allowed.</para> </blockquote>

<sect3 id="gfdl-0"> <title>PREAMBLE</title>

<para>The purpose of this License is to make a manual, textbook,
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<para>This License is a kind of "copyleft", which means that
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<para>We have designed this License in order to use it for manuals
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</sect3>

<sect3 id="gfdl-1"> <title>APPLICABILITY AND DEFINITIONS</title>

<para>This License applies to any manual or other work that
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<sect3 id="gfdl-2"> <title>VERBATIM COPYING</title>

<para>You may copy and distribute the Document in any medium,
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<para>If the required texts for either cover are too voluminous to
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<para>If you publish or distribute Opaque copies of the Document
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</sect3>

<sect3 id="gfdl-4"> <title>MODIFICATIONS</title>

<para>You may copy and distribute a Modified Version of the
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<orderedlist numeration="upperalpha"> <listitem><para>Use in the
Title Page
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</listitem>

<listitem><para>List on the Title Page,
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</listitem>

<listitem><para>State on the Title page
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</listitem>

<listitem><para>Preserve all the
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</listitem>

<listitem><para>Add an appropriate
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</listitem>

<listitem><para>Include, immediately
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</listitem>

<listitem><para>Preserve in that license
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</listitem>

<listitem><para>Include an unaltered
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</listitem>

<listitem><para>Preserve the section
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</listitem>

<listitem><para>Preserve the network
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<listitem><para>In any section entitled
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</listitem>

<listitem><para>Preserve all the
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</listitem>

<listitem><para>Delete any section
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<listitem><para>Do not retitle any
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</listitem> </orderedlist> <para>If the Modified Version includes new
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<para>You may add a section entitled "Endorsements", provided it
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<para>You may add a passage of up to five words as a Front-Cover
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<para>The author(s) and publisher(s) of the Document do not by
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</sect3>

<sect3 id="gfdl-5"> <title>COMBINING DOCUMENTS</title>

<para>You may combine the Document with other documents released
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<para>The combined work need only contain one copy of this
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<para>In the combination, you must combine any sections entitled
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</sect3>

<sect3 id="gfdl-6"> <title>COLLECTIONS OF DOCUMENTS</title>

<para>You may make a collection consisting of the Document and
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<para>You may extract a single document from such a collection,
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</sect3>

<sect3 id="gfdl-7"> <title>AGGREGATION WITH INDEPENDENT WORKS</title>
<para>A compilation of the Document or its derivatives with other
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    as a Modified Version of the Document, provided no compilation
    copyright is claimed for the compilation.  Such a compilation is
    called an "aggregate", and this License does not apply to the other
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<para>If the Cover Text requirement of section 3 is applicable to
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</sect3>

<sect3 id="gfdl-8"> <title>TRANSLATION</title>

<para>Translation is considered a kind of modification, so you may
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</sect3>

<sect3 id="gfdl-9"> <title>TERMINATION</title> <para>You may not copy,
modify, sublicense, or distribute the
    Document except as expressly provided for under this License.
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</sect3>

<sect3 id="gfdl-10"> <title>FUTURE REVISIONS OF THIS LICENSE</title>

<para>The Free Software Foundation may publish new, revised
    versions of the GNU Free Documentation License from
    time to time.  Such new versions will be similar
    in spirit to the present version, but may differ in
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<para>Each version of the License is given a distinguishing
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</sect3>

<sect3 id="gfdl-11"> <title>How to use this License for your
documents</title>

<para>To use this License in a document you have written, include
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<blockquote><para> Copyright (c)  YEAR	YOUR NAME.
      Permission is granted to copy, distribute and/or modify this
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</para></blockquote>

<para>If you have no Invariant Sections, write "with no Invariant
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<para>If your document contains nontrivial examples of program
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</sect3> </sect2> </sect1>

</article>