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FATSAVE V2.0 is Copy(c)right 1989,1994 by Gary Raymond, New Orleans, La.

SAVE your FAT Sectors and restore if necessary!
Another powerful utility from the DiskSave Series by

Gary Raymond
POB 8184
New Orleans, La. 70182

Tech Help (504) 288-6550
E-Mail CIS [70613,3165]
====================================================================

Files Provided:
FATSAVE.COM Dos Disk FAT Save Utility
FATSAVE.DOC This document.

System requirements: PC/XT/AT, DOS 3.0 up, 128k ram up, floppy or
hard drive, mono or color, any type graphic adapter.

For technical information about this utility see end of doc.
====================================================================

Q What is FATSAVE?
A This is a very powerful com utility, written in assembler, whose
purpose is to preserve a copy of your hard drive's critical FAT
sector or File Allocation Tables. Do not be misled by the small size
of the utility. It was written in assembler for speed and accuracy.
FATSAVE copies the FAT sectors from your hard disk media to a file
called FATFILE.OF? on any formatted floppy from where it can be
restored back to the hard drive later, if required. The "?" contains
the letter designator of the drive that had its FAT saved in this
file.

Q Why is the FAT important?
Without an accurate file allocation table, dos cannot locate your
data correctly on the disk storage media. The FAT is a potential
target of viruses as well as being vulnerable to errors in poorly
written database software. The FAT can also be corrupted by users who
enjoy experimenting with their pc systems.

Q Suppose the data saved was not accurately written to my backup disk?
A You run this risk anytime you use any dos copy functions. However,
dos does provide for some minimal crc read/write error checking by
setting the dos copy verify flag on. This still does not guarantee
an intrinsic copy but does offer a little more protection. You can
turn Verify ON by including the "V" switch on the command line.

Example FATSAVE a: b: V or FATBACK b: a: V

Using the dos verify option slows things down a bit, but because
you are dealing in fractions of a minute, it should not matter.

Q What is more preferable, using FATSAVE or doing a FULL system data
backup?
A Unquestionably, nothing give more peace of mind than a current backup
of all your data. This is what you definitely SHOULD do! However, the
practicality of life frequently interferes with things we know we
should do but somehow never seem to manage. Suppose you have a 200meg
hard drive. If you are fortunate to have a backup system that will
scan for files changed after a particular date at the end of the day,
and save them to a separate device, you are most fortunate. If you do
not have such a backup system, and you seldom do manual backups of
your dynamic data, you are basically a sitting duck waiting and
testing fate. Although FATSAVE cannot guarantee 100% restoration of
your data in the event of FAT corruption, it does come close and is
very FAST and EASY to use. FATSAVE will use less than 30 seconds to
save the FAT of a 200 meg hard drive. See suggestion on the best
method to put FATSAVE to work at the end of these Q&A's.

Q Does FATSAVE work on any type drives?
A Yes, FATSAVE will work on most all size or types of dos drives from
floppies to high density hard media. Before FATSAVE attempts to read
the file allocation tables, it first reads the Drive Parameter Block
(DPB) saved by Bios in memory at bootup. From the DPB it determines
the beginning sector location as well as the total number of FAT
sectors on the disk to be FATSAVED. In this way, FATSAVE knows
exactly what type of disk it has been asked to examine. This is
followed by a passive read of the FAT and then a write all of the FAT
data collected to a standard dos file.

Q Why use FATSAVE?
A The majority of times, when a drive fails to read or locate the
content of files properly, and the problem is not the hardware
itself, it is usually due to corrupted FAT data. Remember however, if
the magnetic media has completely failed, (as in a hardware problem)
FATSAVE wont help. But, if the FAT code is corrupted or over written
by a virus, FATSAVE along with FATBACK can save you from a mental
breakdown or worse. FATSAVE can be automatically run from your
autoexec file at boot up, with the FAT data saved to either an
alternate fixed disk or a floppy.

Q Is FATSAVE safe to use?
A Absolutely! FATSAVE does a passive read of the file allocation table
on the drive you are backing up. In this mode, it is impossible for
FATSAVE to change anything in your original FAT area.


Q After reading the FAT data what does FATSAVE do next?
A FATSAVE copies the FAT to a safe buffer area of memory. Then is does
an active write to the destination disk where the FAT code is saved.

NOTES:
There are generally two copies of your FAT saved by dos on your disk.
DOS reads only the first one for finding your file data. But,
whenever changes are made to your data structure, dos writes the
changes to the second copy as well. Because of this, FAT SWAP
utilities seldom work. This is because the second copy is generally
corrupted at the same time as the first copy. The only hope is to
have a RECENT virgin copy of the first FAT preserved at all times.


Q How is the data saved or stored on the backup disk?
A FATSAVE write the data to a standard dos file called FATFILE.OF?,
where the "?" is dynamically stamped at creation time with the drive
letter designator of the disk that a copy of the FAT was made FROM.
Therefore, FATFILE.OF? is a file containing the FAT of your drive C:.

Q Can I use any size or type of floppy to save my FAT?
A Yes, take any type or size blank floppy and format it in the
conventional manner with the operating system installed. Copy
FATSAVE.COM to the formatted floppy disk. If you wish to copy the FAT
of C: drive to a file on A: drive type FATSAVE C: A: at the dos
command prompt. FATSAVE will create a file called FATFILE.OF? with
the FAT data in it, located on the A: drive floppy disk.

That's all there is too it! REMEMBER: Save this floppy disk in a safe
place. It could possibly save you later from a nervous breakdown!



R E S T O R A T I O N U S I N G F A T B A C K

**********************************************************************

Q What is FATBACK?
A FATBACK is a very powerful utility, written in assembler, whose
purpose is to restore a copy of your hard drive's critical FAT or File
Allocation Tables. FATBACK reads the FAT sector data from the backup
file, FATFILE.OF?, (originally saved by FATSAVE on a backup disk) and
uses that FAT data to restores the original drives file allocation
tables.

Q What is more preferable, using FATBACK or doing a FULL system data
backup?
A Unquestionable, nothing give more piece of mind than a current backup
of all of your data. This is what you definitely SHOULD do! However,
the practicality of life frequently interfere's with thing we know we
should do. Suppose you have a 200+ meg hard drive. If you are
fortunate enough to have a backup system that will scan for files
changed after a particular date, at the end of every day, and then
save them, you are most fortunate. If you do not have a data backup
system, and you seldom do manual backups of your dynamic data, you
are basically a sitting duck waiting and testing fate. If data was
lost through corruption of the file allocation tables, FATBACK can
guarantee 100% restoration of your data, plus it is very FAST and
very EASY to use. FATBACK will use less than 30 seconds in most cases
to restore your FAT tables! See suggestion on how to use FATBACK at
the end of these Q&A's.

Q Does FATBACK work on any type drives?
A Yes, FATBACK will work on most all size or types of dos drives from
floppies to hard media. There are no restriction.


Q When should I use FATBACK?
A The majority of times, when a drive fails to read properly, and the
problem is not the hardware itself, it is usually due to a corrupted
FAT sector. Remember, if the magnetic media has completely failed, (a
hardware problem) FATBACK wont help. But, in some instances, where
the magnetic media is weakened by time and has not been refreshed
(rewritten) recently, FATBACK could possibly still help. The big
problems occur if the FAT data is unintentionally corrupted by
experimentation or over written by a virus. Here FATBACK can save you
from a mental breakdown or worse.


Q Is FATBACK safe to use?
A Yes, but FATBACK does WRITE to a critical area of your disk. So, like
any powerful tool, FATBACK require that you observe lots of CAUTION!
Example: Always make sure the FAT backup file you are about to use
for the restore is the SAME one originally saved by FATSAVE for THAT
drive! You can still recover from even this kind of mistake as long
as you have the original, current FAT backup file. FATBACK is NOT a
toy, so don't treat it as such. It is a very powerful tool. In most
cases, if you need to use FATBACK, you already have major disk
trouble and only stand to gain if it restores your drive.


Q How is the data read from the backup disk?
A FATBACK reads the data from a standard dos file labeled FATFILE.OF?
that was originally saved by the companion utility, FATSAVE.COM.


Q Ok, I have a recent backup copy saved of my FAT and a virus scrambled
my disk. How do I use FATBACK to restore the original FAT.
A First, do not attempt to restore your FAT unless you have no other
options. The reverse process WILL write to your FAT sector and you
should only do a FATBACK if one or more of the following conditions
exist:

1) The data on your disk media appears to be completely scrambled
and it is determined that the problem is NOT a hardware problem.

2) You suspect that you may have had a virus that scrambled your
file allocation tables.

3) You absolutely know you corrupted your own FAT by experimenting
with your system. (not too uncommon today)


Q Alright, you sold me. But, if I need to recover my FAT, exactly how
is that done?
A It is as easy to recover with FATBACK as it was to copy or back up
your FAT sectors with FATSAVE in the first place. Assuming you have
re booted your system with a known good and un infected floppy in
drive a: (with a copy of FATBACK and the original FATFILE.OFC on it),
type the following at the a: prompt

FATBACK A: C:

That's all there is too it. If the original FAT was not damaged prior
to backup and the backup copy was very recent, your HD should be able
to locate its data once again. Depending on just how recent your
backup FAT copy is will determine whether or not you will recover
100% of your data or lose a few files. Even then, cleaver use of an
absolute disk editor like the shareware ZipZap job will allow you to
scan for, locate and re save lost chains of your data.

Remember, FATBACK is NOT a toy. Although FATBACK is engineered to be
as safe as possible to use, FATBACK is a lifeboat, and nothing more.
You only use FATBACK when you have no other options. The FATBACK
utility is provided free with registration of FATSAVE.

SUGGESTIONS for using FATSAVE:

Add a few lines to the end of your autoexec.bat that will optionally
run FATSAVE first thing after bootup and save a FAT copy to your
alternate hard drive or a floppy.

ECHO Put a Disk in Drive A for FAT Backup NOW,
ECHO or, hit Ctrl C to abort this operation, or
PAUSE
FATSAVE C: D:

By hitting Ctrl C you can abort the remainder of the batch operation
if you desire. If this operation is done at least every time you
boot up your computer, the likely hood of loosing very much data
in the event of some misfortune is greatly reduced.

====================================================================
V2.0 10/15/93 First public release
====================================================================

ÚÄÄÄÄÄÄÄÄÄ¿
³ MEMBER ³ Society of
³ ÚÄÄÄÄÄÄÁÄÄ¿ Independent
³ ³ ³ Shareware
ÀÄÄ´ þ ³ Authors
³ º ³
ÀÄÄÄÄÐÄÄÄÄÙ
This program is produced by a member of the Society of Independent
Shareware Authors (SISA). The Society wants to ensure that all valid
shareware principle actually work for you and SISA members. The
principle behind shareware distribution is simple; try before you
buy. Society members agree to license all shareware for a minimum of
10 days, free of charge, to first time users as an evaluation
period. After 10 days, buyers are then obligated to license their
copy with the Society member. Society members are obligated to
provide high quality, useful shareware, but, are free to choose
whatever marketing methods suit their specific needs. SISA
sanctioned marketing methods include: demonstration versions;
providing printed documentation after purchase; registration keys
that unlock additional features not necessary to determine basic
usefulness; and, providing bug fixes free of charge. Any Shareware
author may become a member of SISA without cost by simply agreeing
to the above conditions and displaying, at their option, this logo
in their documentation.
====================================================================

WARRANTY:
Software:
Gary Raymond warrants that the software contained herein will
perform in substantial compliance with the documentation
accompanying the software. If you report, in writing, a significant
defect to us, and we are unable to correct it within 90 days of the
date you report the defect, you may return the software and
accompanying materials, and we will refund the purchase price.

Diskette's and Documentation:
Gary Raymond, warrants all diskette's and documentation to be free
of defects in materials for a period of 30 days from the date of
purchase. In the event of notification within the warranty period of
defects in any materials, Gary Raymond will replace the defective
diskette or documentation.

Remedies:
The remedy for breach of the warranty shall be limited to
replacement and shall not encompass any other damages, including but
not limited to loss of profit, special, incidental, consequential,
or similar damages, losses, or claims.

DISCLAIMER:
Gary Raymond specifically disclaims all other warranties, expressed
or implied, including but not limited to, implied warranties of
merchantability and fitness for a particular purpose with respect to
defects in the diskette and documentation, and the program license
granted herein, in particular, and without limiting operation of the
program license with respect to any particular application, use, or
purpose. In no event shall Gary Raymond be liable for any loss of
profit or any other commercial damage, including but not limited to
special, incidental, consequential or other damages.

GOVERNING LAW:
This statement shall be construed, interpreted, and governed by the
laws of the State of Louisiana.
====================================================================

Registering your copy will help continue the competitive advantages
of providing economical shareware. Upon receipt of your payment I
will provide you with a copy of the latest version and notify you of
all future upgrades. Your patronage is appreciated.

My no nonsense license:
------------------------
Your one time registration fee will license you to use FATSAVE on any
number of personal computers owned directly and personally by you.

Re distribution via electronic transmission, or down loading, is
allowed without further permission. Re distribution of the Shareware
version of FATSAVE, for a fee, is also allowed without further
permission as long as that cost is limited to no more than two
dollars per copy, if supplied on any physical disk media.

The assembler source code for BOOTSAVE.COM, BOOTBACK.COM, FATSAVE.COM
and FATBACK.COM is available for sale at $50 per copy. The source is
based on Eric Isaacson's A86 assembler compiler.


Yes Gary, I can really make use of your program and would like to
register and obtain the latest version as well as get on your mailing
list for future upgrades and new releases!

Product: FATSAVE V2.0 $5.00 including shipping (usa only)
Product: FATBACK V2.0 N/C with registration


SPECIAL OFFER: Register both BOOTSAVE and FATSAVE and get a Twenty
Percent discount [$10 -$2] = only $8.00 for
BOTH and still get BOOTBACK and FATBACK FREE!


Name_____________________________________________________________

Mailing Address__________________________________________________

City & State ___________________________________________________

ZIP _____________________________ Phone _________________________

Send registration check or money order to:

Gary Raymond
POB 8184
New Orleans, La. 70182

Tech Help (504) 288-6550
E-Mail CIS [70613,3165]
====================================================================

TECH DATA:
These utilities use DOS Function 25 and 26 of Interrupt 21 in the
"extended" mode in conjunction with Function 1F of 21 to get exact
details of the drive via the dos DPB or Drive Parameter Block. This
data is in turn passed to the extended parameter status block created
for Function 26 and 26. To further insure data transfer integrity,
data is only moved one full sector at a time (512 bytes worth). In
addition, Function 2E of Int 21 is used to toggle the dos Verify
flag at the option, via command switch, of the user. These utilities
were beta tested on over fifty different make and model dos drives
with complete reliability. No testing was performed on networks or
operating systems other than dos 3.0, 3.1, 3.2, 3.3, 4.0, 5.0 and
6.0. PC DOS, MS DOS and DR DOS were all tested satisfactorily.

ACKNOWLEDGEMENTS:
-----------------
To my best friend and machine code instructor, the Padre, alias,
Machine Man, whose many patient hours of coaching and prodding over
the years helped me learn assembler so that I could create this and
many other useful dos utility.

EOF