Trademarked names are the property of the respective owners

(c) Copyright 1990, 1991, F.M. de Monasterio
All rights reserved

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DRIVERs version 1.01
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PROGRAM DESCRIPTION

DRIVERs is a small program that lists the device drivers installed in your
system. A device driver is a special type of resident program that allows
DOS to communicate with a peripheral component of the system, passing data
between the programs and a device. Typically, device drivers are installed
via the CONFIG.SYS file with the DEVICE command:

DEVICE=[d:][path]filename[.ext][parameters]

where the items enclosed in brackets are optional portions of the command.
A 'header block' in the device driver provides information about the type,
name, and attributes of the device. DRIVERs shows much of this information
in a tabular manner.


The following listing is an example of such a display:


Device Header at Strp Intp /--- bit 15-11 ---\ b06 /--- bit 04-00 ---\
name segm:offs offs offs Chr IOc IBM Net OCR Gen Spc Clk NUL StO StI
======== ========= ==== ==== --- --- --- --- --- --- --- --- --- --- ---
NUL 0070:25D8 1599 159F * *
L: 0BFB:0000 00AC 00B5 *
K: 0BDA:0000 00AC 00B5 *
EMMXXXX0 0B1D:0000 0046 004B *
CON 0070:016E 060C 0617 * * * *
AUX 0070:0180 060C 061D *
PRN 0070:0192 060C 063A * * *
CLOCK$ 0070:01A4 060C 0660 * *
A: J: 0070:01B6 060C 0666 * * *
COM1 0070:01CA 060C 061D *
LPT1 0070:01DC 060C 0640 * * *
LPT2 0070:01EE 060C 0648 * * *
LPT3 0070:0200 060C 0650 * * *
COM2 0070:0212 060C 0623 *
COM3 0070:0224 060C 0629 *
COM4 0070:0236 060C 062F *

Header block bits that are set (i.e. equal to 1) are indicated by '*'; the
header block contains 16 bits (0 to 15), which are described below:


Bit 0 - This bit indicates the associated character device is the Standard
Input device. Always set in the console (keyboard+screen) device CON.

Bit 1 - This bit indicates the associated character device is the Standard
Output device. Always set in the console (keyboard+screen) device CON.

Bit 2 - Designates the dummy device NUL (bit-bucket) that heads the device
queue used by DOS.

Bit 3 - This bit indicates the associated device is the real-time clock of
the system.

Bit 4 - This bit indicates a console driver that handles interrupt 29h, an
undocumented DOS interrupt performing faster console output than other DOS
services.

Bit 5 - This bit is reserved.

Bit 6 - This bit indicates that the associated device (see below) supports
optional driver commands for generic input/output control requests (in DOS
version 3.3+).

Bit 7 throgh 10 - These bits are reserved.

Bit 11 - The bit indicates support of optional driver commands to Open and
Close the device (and Check Removable Media in block devices) in DOS 3.0+.

Bit 12 - An optional attribute indicating a network device. (Introduced in
DOS 3.10, it is not mentioned in the documentation of DOS 3.2 or 3.3).

Bit 13 - For a block device (see below) this bit indicates that the device
may not support the PC-DOS/MS-DOS disk structure standards. For character
devices (see below) it indicates the device supports the Output Until Busy
command in DOS 3.2+.

Bit 14 - Another optional attribute indicating that the device supports I/O
control commands for input and output.

Bit 15 - This bit indicates if the device is for a block device (0) or for
a character device (1). Character devices transfer data one character at a
time (e.g. printer, modem, fax, keyaboard, etc). Block devices operate on
groups of characters, transferring several bytes at a time in a data block
(e.g., disk, tape).

In the example above, the listing for device 'L:' is for xDISK; it shows a
block device accepting input/output control requests and supporting PC-DOS
/MS-DOS disk structure.

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HISTORY

version 1.00 First release.
version 1.01 Added a 32-bit CRC check to check for code corruption.
Also added further encoding to prevent code tampering.

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REGISTRATION

These programs and the documentations (the "Software") are the copyrighted
property of FM de Monasterio (the "author"), who provides the Software and
licenses its use. All rights are reserved.

This Software is part of a user-supported shareware package. If you do not
wish to register the Software package, but would like to use this utility,
please send to the address below a US$5.00 check marked "For Deposit Only"
and payable to "PATIENT CARE FUND, CHILDREN'S HOSPITAL" of Washington, DC.
Users who donate to such a fund may legally keep and use the utility under
the limitations described below.

FM de Monasterio
P.O. Box 219
Cabin John, MD 20818-0219
DISTRIBUTION

You may distribute this Software via magnetic and/or electronic means, but
you are specifically prohibited from:

- Charging fees or asking donations in exchange of or payment
for copies of the Software.
- Distributing this Software with commercial products without
the written permission from the author.
- Distributing this Software via a for-profit organization or
group, either alone or with other Software.

The unauthorized copying, decompiling or disassembling of this Software is
prohibited; any other use of this Software is prohibited without a written
permission in advance from the author.


WARRANTY DISCLAIMER

The author cannot and does not warrant that any function contained in the
programs will meet your requirements, or that the operation will be error
free. The entire risk as to the Software performance or quality, or both,
is solely with the user and not the author. You assume responsibility for
the selection of the program to achieve your intended results and for the
installation, use, and results obtained from the Software.

The author makes no warranty, either implied or expressed, including with-
out limitation any warranty with respect to this Software documented here,
its quality, performance, or fitness for a particular purpose. In no event
shall the author be liable to you for damages, whether direct or indirect,
incidental, special, or consequential arising out the use of or any defect
in the Software, even if the author has been advised of the possibility of
such damages, or for any claim by any other party.

All other warranties of any kind, either express or implied,including but
not limited to the implied warranties of merchantability and fitness for
for as a particular purpose, are expressly excluded.


LIMITATION OF REMEDIES

The author's entire liability, and your exclusive remedy shall be: (1) the
replacement of an original Software diskette not meeting the above Limited
Warranty and which is returned to the author along with proof of purchase,
or (2), if the author is unable to deliver a replacement diskette which is
free of defects, you may terminate the License Agreement by returning this
Software and the corresponding license fee will be returned.

By using the Software, you acknowledge (1) to have read and understood all
parts of this document and (2) to have agreed with and accepted all of its
provisions without any reservation.

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