README - datagen Version 1.4.0 - Data generator for DOS
Copyright (C) 2004-2005 dondalah@ripco.com (Dondalah)

This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to:

	Free Software Foundation, Inc.
	59 Temple Place - Suite 330
	Boston, MA  02111-1307, USA.

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This is the DOS version of datagen.  There is a Linux
version of datagen that includes a specification language.
The DOS version of datagen contains only a subroutine
library and a few test programs.  The test programs,
tst.c, tst2.c, and sample.c contain examples of how
the subroutines are called.  The parameters for each
subroutine call are contained in the dgfmt structure. Each
test program shows you how to set up those parameters for
each data type and its subroutine.

The Linux version of datagen contains real time options.
Those options are not included in the DOS version.  If
you want to generate data in real time in DOS, then
modify your host program to include wait states in
between data generation subroutine calls.

There is a trade off between ease of use and speed of
execution.  The editing in the subroutine library has
been de-emphasized in favor of faster execution.  Make
sure that you emulate the sample calls in tst.c to assure
the accuracy of your output.

Datagen is designed to run in real mode in lower memory.
Extended memory is not used.  The memory model is "huge".

To install datagen in DOS,
	Install Borland's free Turbo C, version 2.0.
	Extract all the files from datagen-1.4.0.dos.zip.
	Change directory to datagen-1.4.0.
	Modify the turboc.cfg file to point to Turbo C.
	Run instdg.bat.
        Run run.bat to test the subroutine library.

To de-install datagen, run "deinst.bat".

The test programs are:

tst.c - contains call examples for all data types.

tst2.c - contains call examples with wait states.

sample.c - contains a minimal data generator.  You
           may modify this file for your own generator,
           emulating sample calls in tst.c.

g2jd.c - date conversion to aid in setting up the dgdtrng()
         call.  This program converts from the Gregorian
         format to julian day.

jd2g.c - date conversion to aid in setting up the dgdtrng()
         call.  This program converts from the julian day
         format to the Gregorian format.

The Linux version of datagen is in a separate package,
called datagen-1.4.0.tar.gz.  This version also contains
a subroutine library that functions like the DOS library.
You can use the libraries on both Linux and DOS to test
conversion programs from DOS to Linux and back.

Suppose you have a Windows system that you want to
convert to Linux.  Run datagen in DOS to set up test
transactions for the Windows system.  Then after
converting the system to Linux, run the same transactions
on the Linux system to verify the validity of your
conversion.

The algorithms in the DOS version have been adapted to
a 16 bit, real mode, environment.  Therefore they do
not match the output of the datagen language in Linux
with the same seeds.  However the output from the rnd()
subroutine matches in both DOS and Linux.

I could have easily created the same datagen library
in the Windows, 32 bit, environment.  But then you
would have to use an expensive compiler to compile
the library.  Therefore the choice was made to give
you a library to compile on a free compiler.

If you encounter problems, please send me:

	A detailed description of your compile steps.
	A detailed description of the problem.
