Sizeable RAMDisk version 1.10
                          for XMS memory only

                                 Author
                             Marko Kohtala

                             PUBLIC DOMAIN


No rights reserved. All parts of this product may be reproduced,
stored in a retrieval system, or transmitted by any means, electronic,
mechanical, protocopying, recording, or otherwise, without written
permission from the author. No patent liability is assumed with respect
to the use of the information contained herein. While every precaution
has been taken in the preparation of this product, the author assumes no
responsibility for errors or omissions. Neither is any liability assumed
for damages resulting from the use of the product documented herein.



CONTENTS

  1. Publishing purpose, features included and recognised missing
  2. Files in this release
  3. Usage
  4. Technical data for further development
  5. Last words



    1. PUBLISHING PURPOSE, FEATURES INCLUDED AND RECOGNISED MISSING

This RAM disk driver is published in the hope we will get a really good
RAM disk that is entirely public domain. I do not intend to make it all
out myself but rather hope there is out there someone who is willing to
participate in my work.

This RAM disk currently supports the following features:

  * XMS (Extended memory on 286 and up) support - no other memory
    supported - yet
  * Resizeable/removable - destructive
  * Configurable
      - sector size
      - cluster size
      - root directory entry count
      - number of FATs
  * Write protection
  * DOS versions from 3.00 to 5.x (tested only with DOS 5.0)

What I would like to see added:

  * EMS support
  * UMB support
  * Bank-Switch memory support ("The Last Byte" by Key Software)
  * Low memory support
  * Any combinations of those above (Bank-Switch+XMS/EMS mostly)
  * Resizing of the disk without loosing disk contents



                        2. FILES IN THIS RELEASE

The following material is distributed in this release:

        SRDISK.DOC      this document
        SRDISK.C        disk formatter source code for Turbo C++ 1.0
        RDISK.ASM       the device driver source code for XMS
        RDISK.SYS       the compiled device driver
        SRDISK.EXE      formatter program for the RAM disk



                                3. USAGE

To use the RAM disk, you must have the device driver installed at boot
time. This can be done by copying the RDISK.SYS to your root directory
and including the line

        DEVICE=RDISK.SYS

to your CONFIG.SYS file.

After this change, when you boot your machine you should see a sign-on
message close like "Sizeable RAMDisk version x.xx virtual drive d:"
without any annoying error messages.

If you see error messages, you may have forgotten to install the XMS
driver (eg. HIMEM.SYS), or you have improper DOS version or something.
Try to fix the problem. If you fail... sorry.

If no errors are detected, you have no ramdisk. If you try to use that
disk mentioned on the sign-on message, you'll notice the disk is not
ready. That is because the ramdisk has not been enabled yet. For that
you need the SRDISK.EXE.

The disk can be enabled by, for example, using command "SRDISK d: 1024"
which will make disk d: a 1024K disk.

The SRDISK is self documented. You'll get the documentation by typing at
the DOS prompt "SRDISK /?" and hitting enter.



                4. TECHNICAL DATA FOR FURTHER DEVELOPMENT

The job is split between the device driver and the SRDISK program this
way:

Device driver does:

  * What ever a RAM disk driver is expected by the DOS to do

  * Support IOCTL calls using the one defined data packet. The packet
    contains the following data:
      - BIOS parameter block for the drive
      - disk size in K-bytes
      - read/write access flags (read flag is actually enabled flag)
      - media status byte to tell if the media has been changed
      - number of open files on drive
      - pointer to the sector read/write function in the driver

  * Allocate, reallocate and free what ever disk memory is used by the
    driver

SRDISK does:

  * Send the driver the new disk format

  * Format the new disk i.e. write the boot sector, FAT(s) and root
    directory according to the format sent to driver

I've done it this way because I did not want to bother myself adding the
SRDISK functions to the driver too.

The sources are somewhat documented.



                             5. LAST WORDS

Although no rights are reserved, I HOPE you will send any modified
versions, new drivers, better documentation, bug reports, suggestions
and your love (preferably female) to me.

I'd like the modifications to sources as patches to some version the
number of which you should tell.

Make sure every material you contribute is in public domain. I do not
want to add any copyright texts to this product. While I was starting
this thing, I tried to find some PD sources where to start and found
none - I only got frustrated. I hope to fix that too.

I'll make a list of every people contributing material to this product
and ship it with further releases.

You can contact me by sending E-mail from

        Internet, Bitnet etc. to 'mkohtala@niksula.hut.fi'
        CompuServe to '>INTERNET:mkohtala@niksula.hut.fi'

or by calling Airline QBBS, 24H, HST, V.32, V.42, MNP, +358-0-8725380,
and leaving mail to me, Marko Kohtala.