








                          README for XFree86 on OS/2

                                  Holger Veit

                      Last modified on: December 29, 1998



1.  Introductory Note about the release 3.3.3

Before looking into this file, please check for any LATEST.OS2 files that may
come with the binary distribution. Please also check out the following
XFree86/OS2 WWW pages:

   o http://set.gmd.de/~veit/os2/xf86os2.html

   o http://set.gmd.de/~veit/os2/xf86bugs.html

   o http://set.gmd.de/~veit/os2/x11os2faq.html

before you claim to have found any problems.

This version of the code is called XFree86/OS2 3.3.3. This is a bugfix release
for 3.3 and later which also adds hardware support for some newer cards
(including AGP boards). XFree86-3.3.3 contains all security fixes that were
released for earlier versions. See the RELNOTES document for details.

XFree86/OS2-3.3.3 is a full, unrestricted version which does not expire, and
for which the complete  source code is available. In contrast to beta versions,
we consider this  code as sufficiently stable for use by an end user. Since
there  have been numerous bugfixes, we recommend this version, even if you had
XFree86/OS2 3.3 before and it worked satisfyingly with your hardware. By the
time 3.3.3 is released, the older version 3.3 will be withdrawn, and archives
will be updated to this version. There may still be references  to 3.3 still in
documents; these apply to 3.3.3 as well, unless otherwise noted.

Previous versions have been tested in a large number of configurations and have
been found to be working, with some bugs left, rather flawlessly.

This release is almost complete (with a few exceptions) regarding the X11R6.3
``core'' distribution. A subset of the ``contrib'' distribution is available
from the ported software page http://set.gmd.de/~veit/os2/xf86ported.html

In the past beta testing, it has been found that the software itself is rather
stable and does not damage hardware - provided the user does not try to push
the builtin limits and change certain configuration parameters which could
operate the video hardware out of specs.

However,

   o even with a code we consider stable there is no explicit or implicit war-
     ranty that certain code works correctly or works at all


README for XFree86 on OS/2                                                    1





README for XFree86 on OS/2                                                    2



   o although no damage reports are known, it does not mean that it is impossi-
     ble to damage hardware with this code; some deeply hidden bugs may still
     be present in the software.

It is recommended that you backup essential data of your system before
installing this software, but this should be your general precautions before
ANY installation. No reports exist that a crashing X server itself actively
destroys or modifies data, but it is possible in rare cases that the system is
left in an unusable state (video display mode garbled or system unresponsive,
not reacting to mouse or keyboard actions).  If you then hard reset or switch
off the system, file caches of the operating system might not be written cor-
rectly back to disk, thus causing data loss.


2.  What and Where is XFree86?

XFree86 is a port of X11R6.3 that supports several versions of Intel-based
Unix.  It is derived from X386 1.2, which was the X server distributed with
X11R5.  This release consists of many new features and performance improvements
as well as many bug fixes.  The release is available as source patches against
the X Consortium X11R6 code, as well as binary distributions for many architec-
tures.

XFree86/OS2 is the name of the implementation of XFree86 on OS/2 based systems.

See the Copyright Notice.

Binaries for OS/2 Warp and Merlin are available from:
ftp.XFree86.org:/pub/XFree86/3.3.3/OS2

The WWW page http://borneo.gmd.de/~veit/os2/xf86os2.html will usually show more
references to FTP or WWW sites to retrieve sources or binaries.

Other versions:

XFree86/OS2 will run on all dialects of Warp 3, including Warp "red spine box",
Warp "blue spine box", Warp Connect, Warp Server, and Warp 4.

For Warp 3 installing fixpack level 17 or later is strongly recommended.  There
have been a few reports that the installation of FP26 causes XFree86 no longer
to work, but I am not sure about a real reason. Current fixpacks for Warp 3,
like FP36, seem to work well also.

Warp 4 may be used with or without the recent public fixpack.

Please check in all cases a LATEST.OS2 file.

OS/2 2.11 is not supported any longer with this release, due to lack of a work-
ing test environment. Consequently, OS/2 SMP 2.11 is not supported either. Warp
Server SMP is supported, but SMP does not give significant advantage, other
than the general speedup because of multiple processors working. OS/2 versions
1.X are definitely not supported and will never be.

It is possible to build XFree86/OS2 from the sources.  Read about this in the








README for XFree86 on OS/2                                                    3



document OS2.NOTES.


3.  Bug Reports for This Document

Send email to Holger.Veit@gmd.de (Holger Veit) or XFree86@XFree86.org if you
have comments or suggestions about this file and we'll revise it.


4.  Hardware and Software Requirements

4.1  Supported, Required, and Recommended Hardware

   o At least a 486DX33 with 16MB RAM is required. A Pentium or Pentium Pro and
     more main memory is recommended. A 386 or a system with 8MB or less memory
     is an insufficient configuration.

   o There are no specific requirements concerning network cards, disk types,
     or CD ROM equipment; of course the more powerful, the better.

   o Depending on the packages installed, a disk space of 20-55MB on a HPFS
     formatted partition (or a NFS or ext2fs partition natively allowing long
     filenames) is required. XFree86/OS2 will not run on FAT partitions.

   o You need a video card that is supported by XFree86. Refer to the general
     README document for a list of supported cards. Note that the sets of video
     cards supported by XFree86 on one hand and OS/2 on the other hand overlap,
     but do not match exactly, i.e. the fact that your card is supported by
     OS/2 does not mean it works with XFree86 as well, and vice versa. XFree86
     does not use the video services of the OS/2 operating system.

4.2  Required Software

   o Any version of Warp 3 with at least fixpack 17, or Warp 4 is required

   o XFree86/OS2-3.3.3 may use a local named-pipe connection or a TCP/IP based
     network connection.

       1.  Warp comes with the Internet Access Kit (IAK), which is sufficient.
           Warp Connect and Warp Server come with a full version of TCP/IP
           (3.0). Use of this software is preferred over IAK then.

       2.  Warp 4 comes with TCP/IP 4.0 which should also work.

       3.  There are reports that with EMX 0.9 fix 4, you can also use the new
           32 bit IBM TCP/IP 4.1 product.

       4.  The old IBM TCP/IP 2.0, that comes with the IBM PMX product may be
           used with Warp as well, although it is no longer supported by IBM.
           Please ensure that you have the latest CSDs installed.

     Other versions of TCP/IP, such as FTP's, DEC's, or Hummingbird's TCP/IP
     versions, as well as IBM TCP/IP 1.X are not supported. Nor does any net-
     working support from DOS (packet drivers, winsock), Netware, or NetBIOS








README for XFree86 on OS/2                                                    4



     work, and I won't to provide support for that in the future.

   o If you want to write or port applications for XFree86, you are encouraged
     to do so. You will need a complete installation of EMX/gcc 0.9C fix4 or
     later for doing so. Neither the second (obsolete) implementation of gcc,
     nor any commercial package, including Cset/2, VAC++, Borland C++/OS2, Wat-
     com C++, Metaware C, and others, is suitable for porting, because various
     parts of the X DLLs rely on certain features only present with EMX.


5.  Installing the System

The binary distribution is composed of a number of zip archives which are the
executables, servers, fonts, libraries, include files, man pages, and config
files.  The full distribution requires about 40-55MB of disk space.

All archives of this alpha version are packed with the info-zip utility, which
is available under the name UNZ512X2.EXE (or a later version) from many OS/2
archives. Please obtain a native OS/2 version of this unpacker.  DOS PKUNZIP
does not work, because it cannot unpack long file names and extended
attributes.

At this moment, the distribution covers only the ``core'' distribution which
somewhat reduces the usability. Refer to WWW sites and archives listed in the
XFree86/OS2 FAQ and elsewhere to obtain pre-built X clients which were ported
to XFree86.

The contents of the packages are:

      REQUIRED:

                  X333base
                        A special device driver and the SuperProbe program

                  X333doc
                        READMEs and XFree86 specific man pages.

                  X333bin
                        all of the executable X client applications and shared
                        libs

                  X333fnts
                        the misc and 75dpi fonts

                  emxrt
                        Runtime libraries of EMX

            Choose at least one of the following to match your hardware:

                  X3338514
                        the X server for IBM 8514/A and compatible boards

                  X333AGX
                        the X server for AGX boards








README for XFree86 on OS/2                                                    5



                  X333Glnt
                        the X server for Permedia / GLINT boards

                  X333I128
                        the X server for #9 Imagination 128 boards

                  X333Ma32
                        the X server for ATI Mach32 graphics boards

                  X333Ma64
                        the X server for ATI Mach64 graphics boards

                  X333Ma8
                        the X server for ATI Mach8 graphics boards

                  X333Mono
                        the Monochrome X Server

                  X333P9K
                        the X server for P9000 based boards

                  X333S3
                        the X server for S3 based boards (excluding S3 ViRGE)

                  X333S3V
                        the X server for S3 ViRGE based boards

                  X333SVGA
                        the 8-bit pseudo-color X server for Super VGA cards

                  X333VG16
                        the 4-bit pseudo-color X server for VGA & SVGA cards.

                  X333W32
                        the X server for et4000w32 based boards

      OPTIONAL:

                  X333man
                        pre-formatted man pages for the X11 interface and
                        clients

                  X333f100
                        100dpi fonts

                  X333fscl
                        Speedo and Type1 fonts

                  X333fnon
                        Japanese, Chinese and other fonts

                  X333fcyr
                        Cyrillic fonts









README for XFree86 on OS/2                                                    6



                  X333fsrv
                        the font server with man pages.

                  X333prog
                        the X11 header files and programmer's utilities for
                        compiling other X applications

                  X333pex
                        PEX fonts and libraries required for PEX applications

In order to save space on your disk and reduce net bandwidth, choose the soft-
ware to obtain carefully. Each X server is an archive of about 1.2MB and occu-
pies 3.0MB on the disk. You won't normally need more than the single Xserver
tailored to your video card.

If it is your first time install, get the X333base archive before any of the
other packages. This package contains a driver and a test program, which ana-
lyzes your video hardware. If this program fails or reports an incompatible
hardware, it makes no sense to obtain the other packages in the hope that they
would magically work.


6.  Troubleshooting

Surprised to see this section directly in the beginning? We have put it here
because chances are best here not to overlook it. This does not mean that you
will necessarily encounter trouble when installing XFree86, but be warned: the
following sections are IMPORTANT and neglecting one or more things out of impa-
tience or sloppiness will leave you with a non-working X11 system and us with
unnecessary problems.

Still, due to the incredibly large number of hardware configurations, there may
be some special situations and configurations where the below description is
not successful. If this happens, read - I repeat READ - the list of ``fre-
quently asked questions'' (FAQ) which has meanwhile evolved to a troubleshoot-
ing guide. The latest version is always at
http://set.gmd.de/~veit/os2/x11os2faq.html .

Maybe - but we found you must be very creative - you find a bug. Consult the
page http://set.gmd.de/~veit/os2/xf86bugs.html whether it is already known. If
not, you have a case and should report it to XFree86 (xfree86@xfree86.org).
Please refer to the FAQ about the information to be provided for a complete
problem report.

The recommended newsgroup for setup questions is comp.os.os2.setup.misc.  I
read this group, so it won't speed up the process or enforce anything if you
post to other groups, or forward the report to my mail address as well or to
xfree86@xfree86.org.

So, not to discourage you completely, the setup section begins:












README for XFree86 on OS/2                                                    7



7.  Checking Compatibility of Video Hardware

In the following, we assume that you want to install XFree86/OS2 on a disk
drive with the letter Y: (which you probably don't have). Change the letter in
all commands accordingly.

  1.  Obtain the package X333base and install it from the root directory of the
      Y: drive, by entering the following commands:

           [C:\] Y:
           [Y:\] cd \
           [Y:\] unzip \path_of_package\X333base.zip



  2.  Edit your CONFIG.SYS file to contain the following line somewhere:

           DEVICE=Y:\XFree86\lib\xf86sup.sys


      Of course replace ``Y:'' with the correct drive letter.

  3.  At this point, you may consider to add the variables required for
      XFree86/OS2 as well, which will save you from one additional reboot.
      Refer to section Adding Variables to CONFIG.SYS (section 9., page 8)
      below.

  4.  After adding the device driver entry to the CONFIG.SYS file, you must
      reboot to install the driver. XFree86/OS2 will not work without this
      driver.

  5.  Start a full screen OS/2 CMD session and enter the following command:

           [C:\] Y:\XFree86\bin\SuperProbe



  6.  This command will (normally) report important information about your
      video configuration, i.e. the type of chipset, the available video memory
      and the RAMDAC circuit available. Please write this down or redirect the
      output of ``SuperProbe'' into a file by entering:

           [C:\] Y:\XFree86\bin\SuperProbe >filename



  7.  SuperProbe can identify many more video cards than are supported by
      XFree86. In some cases, SuperProbe unfortunately detects a wrong card,
      often it claims to have seen a MCGA card which is some sort of a fall-
      back. Generally, if it is approximately right, there are only few reasons
      for doubts; if it is totally off (e.g. saying it has seen a ET4000, and
      you have a Cirrus card), you should report a mis-detection as a bug to
      the given address. In all cases, please take the few minutes and check
      the accompanying README.* files to check for special precautions,








README for XFree86 on OS/2                                                    8



      options, or features of the card.

  8.  If the README files tell you that your hardware is supported, please
      obtain the rest of the software.


8.  Installing the packages

XFree86/OS2 assumes a directory hierarchy starting from drive:\XFree86.  This
can be changed, but is strictly discouraged.

  1.  Choose a HPFS partition with sufficient free space.

  2.  For each package to install, go to the root directory of this drive, and
      type:

           drive:> cd \
           drive:> unzip \path_of_packages\X333xxxx.zip

  3.  You might encounter that some packages report duplicate files, e.g.  the
      X server packages install corresponding README files, which are also in
      the X333doc package. This is okay, the files are the same. Let unzip
      replace the files.

  4.  No special sequence to unpack the files is required.


9.  Adding Variables to CONFIG.SYS

XFree86/OS2 requires a number of settings in the CONFIG.SYS file to work cor-
rectly. Please add the following settings, and in particular take care to set
forward versus backward slashes correctly:

      TERM
            Set the preferred terminal type for the xterm or editor to be used.
            Some programs need this setting. I have my type set to

                 SET TERM=ansi


            \XFree86\lib\X11\etc\termcap.x11 contains a suitable termcap which
            can be used in place of termcap files that come with EMX, EMACS, or
            other ported software.

      TERMCAP
            This variable must be set to the location where the termcap file
            used for the above TERM variable is searched. My setting, for
            instance, is:

                 SET TERMCAP=D:/EMX/ETC/TERMCAP.X11


            Note that forward ``/'' is used as a directory separator.









README for XFree86 on OS/2                                                    9



      ETC
            Set to an ETC directory. Normally, this is already set to the ETC
            directory of the TCP/IP code, such as

                 SET ETC=C:\TCPIP\ETC

      TMP
            Set to an TMP directory. Normally, this is already set to the TMP
            directory of the TCP/IP code, such as

                 SET TMP=C:\TCPIP\TMP

      HOSTNAME
            Set to the internet hostname. Normally, this is already set by the
            TCP/IP installation program, such as

                 SET HOSTNAME=myhost


            With IAK, you would normally run a loopback configuration Network
            configuration (section 10., page 11) and would then set this to

                 SET HOSTNAME=localhost

      USER

      LOGNAME
            Set both to a username. Currently, they are there just to make some
            programs happy; in the future, this variable might be set by a
            login shell of a multiuser configuration. My variable, for
            instance, is set to

                         SET USER=holger
                         SET LOGNAME=holger

      HOME
            Set this to an existing directory that is supposed to be a home
            directory of a user. Some utilities place temporary and init files
            here. This is also future investment for a multiuser configuration,
            but must still be there. For instance, this variable might be set
            to

                 SET HOME=H:\user\holger

      X11ROOT
            This is one of the most important settings, it determines the root
            of the XFree86 directory tree. Normally, you will set this to the
            drive letter of the partition where the \XFree86 tree resides, such
            as in

                 SET X11ROOT=Y:


            You may try to move the tree to another subdirectory, e.g. to








README for XFree86 on OS/2                                                   10



            K:\OS2\X11\XFree86... and would then have to change this to

                 SET X11ROOT=K:/OS2/X11

            , but this is discouraged, since some utilities might not accept
            this.  Note the forward ``/'' as a directory separator here.

      DISPLAY
            This variable may be set to the display to be used for displaying
            clients. Normally you will set this variable to the same value as
            the HOSTNAME variable and simply add a :0.0 after it, such as

                 SET DISPLAY=myhost:0.0


            Read the X11 man page on the exact meaning of these postfixes and
            other options.

      XSERVER
            Set this to the executable name of the X server to be used. This
            must be a complete path. My setting is as follows:

                 SET XSERVER=D:/XFree86/bin/XF86_Mach64.exe

      PATH
            Add the binary directory for the X11 utilities to your search PATH.
            This is normally the directory (adjust the letter)

                 Y:\XFree86\bin


            It is possible to move the binaries to another directory in the
            search path; for maintenance reasons and clarity of the structure,
            this is not recommended, though.

      LIBPATH
            Add the DLL directory for the X11 utilities to the LIBPATH.  This
            is normally the directory (adjust the letter)

                 Y:\XFree86\lib


            It is possible to move the DLLs to another directory in the library
            path; for maintenance reasons and clarity of the structure, this is
            not recommended, though. Note that Y:\XFree86\lib has several other
            subdirectories; these may not be moved elsewhere, rather they must
            stay there, because most utilities form a path to these directories
            by using %X11ROOT%\XFree86\lib as a base.

The recent version of XFree86/OS2 has a REXX script named checkinstall.cmd
which you can (and should) use to check whether you have entered most things
correctly. This is not bullet-proof, but prevents the most obvious setup prob-
lems. Also, the X server itself will do some checking and will refuse to start
if something is wrong.








README for XFree86 on OS/2                                                   11



10.  Remarks on the Network Configuration

It is beyond the scope of this document to even give an introduction about the
correct installation of the TCP/IP networking system. You must do this yourself
or seek assistance elsewhere. It is only possible to say here that a PC working
well in a TCP/IP based LAN network will also work with XFree86/OS2 (when all
other prerequisites are matched as well).

With IAK, there is a special configuration necessary, unless you want to use
XFree86/OS2 only during a hot link to your Internet provider, the so called
``localhost'' or ``loopback'' configuration. This is a local network interface
which ``loops'' back to the same host. The following settings are necessary for
this:

  1.  Create a file \tcpip\etc\hosts with the following content:

           127.0.0.1  localhost

  2.  Add the following line to your \tcpip\bin\tcpstart.cmd:

           ifconfig lo 127.0.0.1 up


      If you don't have such a tcpstart.cmd file (Warp 4 calls this file
      \MPTN\BIN\MPTSTART.CMD), create one, and add a line like the following to
      your config.sys file: CALL=C:\OS2\CMD.EXE /Q /C C:\tcpip\bin\tcpstart.cmd
      >NUL: (implying that your bootdrive is C:).

  3.  Set the HOSTNAME environment variable to localhost as described in the
      last section.

  4.  Add the following line to CONFIG.SYS:

           SET USE_HOSTS_FIRST=1

  5.  After rebooting, verify that the following command works:

           [C:\] ping localhost

You don't need this ``loopback'' interface if your PC is connected to a LAN
(either directly or through SLIP/PPP).

In case of a SLIP/PPP line, you have to establish this connection BEFORE you
start XFree86.

The checkinstall.cmd script coming with XFree86/OS2 gives some advice on the
configuration as well.

If you have problems to get this or other basic networking things running, seek
assistance elsewhere.












README for XFree86 on OS/2                                                   12



11.  Configuring X for Your Hardware

After you have added the required settings and setup a working network, run the
xf86config program to create a standard configuration file in
Y:\XFree86\lib\X11\XF86Config from a windowed or full screen OS/2 text session:

     [C:\] xf86config

The xf86config program will ask a number of questions. You will need the infor-
mation obtained from the SuperProbe program here. The program should be self
explanatory; if you have problems to understand something though, seek assis-
tance in the newsgroups.

It is possible, but strongly discouraged for the non-expert, to edit the
XF86Config file with a text editor. In a few situations as described in the
FAQ, however, this might even be mandatory. This file is not a hacker's area,
such as the Win95 registry, but it has in common with it that you can easily
cause damage.

For details about the XF86Config file format, refer to the XF86Config(4/5) man-
ual page.

If you know the configuration process from Linux or other XFree86 platform, you
will encounter a few differences:

   o There is no configuration for the mouse type or device. The mouse device
     name is fixed to OSMOUSE, and this cannot be changed.  If you have a
     three-button-mouse, install the correct OS/2 driver for it, such as

          DEVICE=D:\OS2\BOOT\PCLOGIC.SYS SERIAL=COM1
          DEVICE=D:\OS2\BOOT\MOUSE.SYS TYPE=PCLOGIC$


     for a MouseSystems compatible mouse, for instance.

   o The X server does not read the native OS/2 keyboard map, but the new XKB
     server extension might already give you a correct keyboard layout, pro-
     vided your language was selectable in the xf86config program. If you
     encounter incorrect settings, please send a mail to XFree86@XFree86.org
     describing in detail what is wrong. Even with XKB, you have the option to
     replace some key settings with a xmodmap file. See the man page for
     xmodmap for details (or use some available xmodmap file from Linux - they
     are the same).

   o There is no support for the Wacom and Elographics input devices yet.

In most cases, an existing XF86Config file for the same XFree86 version from
Linux or another platform may be used without changes. There is one prominent
exception: some S3 805 based VLB cards put their video memory in odd locations.
The X server can search for this memory by experimentally mapping and unmapping
possible memory regions. In XFree86/OS2, the OS may run out of memory tiles
during this process. If this happens, you must find out the location of the
memory yourself and add it as an option









README for XFree86 on OS/2                                                   13



          MemBase 0x12345678


to the XF86Config file.

Once you've set up a XF86Config file, you can fine tune the video modes with
the xvidtune utility.


12.  Running X

16mb of memory is a recommended minimum for running the network software, X and
the presentation manager in parallel.  The server, window manager and an xterm
take about 4-6 Mb of memory themselves.  X will start up on a system with 8MB
or less, but the performance will severely suffer from heavy disk swapping.
Your mileage may vary, though, so some people might consider this still tolera-
ble.

The easiest way for new users to start X windows is to type:

     [C:\] startx

.

To get out of X windows, type: ``exit'' in the console xterm.  You can cus-
tomize your X by creating .xinitrc, .xserverrc, and .twmrc files in the direc-
tory that the HOME environment variable points to. These files are described in
the xinit and startx man pages.

By default, the systemwide xinitrc file (in Y:/XFree86/lib/X11/xinit/xini-
trc.cmd) installs the rather simplistic twm window manager. You can find better
window managers on the ported software page at
http://set.gmd.de/~veit/os2/xf86ported.html .


13.  Rebuilding the XFree86 Distribution

Do you really want to rebuild XFree86/OS2 from source? Read the file OS2.Notes
on details to recompile XFree86/OS2 from scratch.


14.  Building New X Clients

The easiest way to build a new client (X application) is to use xmkmf if an
Imakefile is included in the sources.  Type ``xmkmf -a'' to create the Make-
files, check the configuration if necessary and type ``xmake''. ``xmake'' is a
wrapper for the GNU make program which defeats the improper SHELL setting typi-
cally found in a Makefile generated from an Imakefile. Also see the XFree86/OS2
FAQ for more hints about porting X clients.


15.  Acknowledgements

Many thanks to:








README for XFree86 on OS/2                                                   14



   o Sebastien Marineau for his great work on getting the server code debugged

   o Eberhard Mattes for the wonderful base platform EMX which this port heav-
     ily relies on

   o ME - no, no, forget this: I won't praise myself :-)

     Generated from XFree86: xc/programs/Xserver/hw/xfree86/doc/sgml/OS2.sgml,v 3.9.2.8 1998/12/29 07:54:29 hohndel Exp $





     $XConsortium: OS2.sgml /main/4 1996/03/11 10:46:06 kaleb $
















































README for XFree86 on OS/2                                                   15





































































                                   CONTENTS



1.  Introductory Note about the release 3.3.3 ............................... 1

2.  What and Where is XFree86? .............................................. 2

3.  Bug Reports for This Document ........................................... 3

4.  Hardware and Software Requirements ...................................... 3
    4.1 Supported, Required, and Recommended Hardware ....................... 3
    4.2 Required Software ................................................... 3

5.  Installing the System ................................................... 4

6.  Troubleshooting ......................................................... 6

7.  Checking Compatibility of Video Hardware ................................ 7

8.  Installing the packages ................................................. 8

9.  Adding Variables to CONFIG.SYS  ......................................... 8

10. Remarks on the Network Configuration ................................... 11

11. Configuring X for Your Hardware ........................................ 12

12. Running X .............................................................. 13

13. Rebuilding the XFree86 Distribution .................................... 13

14. Building New X Clients ................................................. 13

15. Acknowledgements ....................................................... 13





















                                       i


