C O N F I G . S Y S
F I L E
B A S I C S

And not so basics

Description of the CONFIG.SYS file:

This file in DOS is responsible for installing device drivers. "What's a device driver" you might say? A device driver is a small program that controls a device. Example: you just bought a new SVGA XT Virtual Reality monitor for your Pentium IIXV computer. Obviously, MS and IBM didn't expect for such a thing to come about so soon. That's why the monitor came with a DEVICE DRIVER that allows your Pentium IIXV to control it. Your config.sys file allows DOS to be able to control VIRTUALLY (Pun ;-) any thing such as: scanners, tape backup drives, CD-ROM's, and big expensive VR monitors. It also allows you to configure your computers memory. I will attempt to explain to you how to set up your config.sys file and take full control of your computer abilities. Now, on with the show...
Commands `O Plenty

DEVICE= filename with path
DEVICEHIGH=

Use this command to install device drivers. You will need to follow the directions that come with the device as to where in your config file they should be placed. You need to be cautious as some need to be installed after extra memory has been mapped and some should come before. DEVICEHIGH does the same except it loads the device driver into the upper memory region, reducing the amount of conventional memory used.
LASTDRIVE= drive letter
LASTDRIVEHIGH=
This lets you set the last drive available to your computer. You can have up to 26 drive letters (A: through Z:) Usually this can be set to the last drive you have installed. I leave a few "extra" drives open so that I can use the SUBST command (See DOS External Commands for usage of SUBST-when I get it up!). If you are memory conscious you wont want to just set it to Z:. DOS allocates around 100 bytes of memory for each drive it "sees" (Don't quote me on this, I am taking a best guess as I sit here writing this). LASTDRIVEHIGH does the same except it reduces the amount of conventional memory used.

SWITCHES=/ switch letter

Put this line in first if you are going to use it. It lets you do the following:

/W allows you to put your WINA20.386 file any where you want
(Note: this waists around 120K of UMB)

/K makes your AT keyboard to emulate a XT keyboard

/F has DOS 6.0 and up skip over the Starting MS-DOS... 2 second waiting period

/N prevents a user from aborting the startup files with F5 and F8 in DOS 6.0 and up

BUFFERS= usually around 20
BUFFERSHIGH=

Buffers are small packets in your computers memory that DOS can store information. This is mostly used for holding data when reading and writing to disks. When you copy something from your hard drive to a floppy disk, the data must be read from drive C:, stored temporarily in memory, and then written to disk A:. Buffers are 512 bytes in length. If you use the SMARTDRV.SYS device driver buffers should be set to 3. Don't ask why. BUFFERSHIGH does the same except it reduces the amount of conventional memory used.

FILES=
FILESHIGH=

This sets the number of files that DOS can have open at once. This should be set to the maximum number specified by your biggest program. Example: Word Perfect 5.1 (Which I still use) requires somewhere around 50 or so files to be open at once. DOS has to be able to access WP.COM, WP.OVL, help files, spell checkers, thesauruses, your current document, and COMMAND.COM itself. Since it probably is one of the largest programs run from DOS (Again, don't quote me on this) it will probably be safe to use the max files setting for it on every boot of your computer. FILESHIGH does the same except it reduces the amount of conventional memory used.

Here is the list of all commands for DOS 7 that come with windoze 95. You can find this list in your C:\Windows\ directory called CONFIG.TXT. I haven't had time to "Convert It To English" yet, but here it is for you to see. Please note: ACCDATE is for DOS 7 only, that is it won't work for DOS 6.22 and below.

ACCDATE
=======

For each hard disk, specifies whether to record the date that files are
last accessed. Last access dates are turned off for all drives when
your computer is started in safe mode, and are not maintained for floppy
disks by default.

Syntax

    ACCDATE=drive1+|- [drive2+|-]...

Parameters

drive1, drive 2...
    Specifies the drive letter.

+|-
    Specify a plus sign (+) to indicate that the last access date should be
    maintained for files on the drive. Specify a minus sign (-) to indicate
    that the last access date should not be maintained for files.


BREAK
=====

Sets or clears extended CTRL+C checking. You can use this command at the
command prompt or in your CONFIG.SYS file.

You can press CTRL+C to stop a program or an activity (file sorting, for
example). Typically, MS-DOS checks for CTRL+C only while it reads from the
keyboard or writes to the screen or a printer. If you set BREAK to ON, you
extend CTRL+C checking to other functions, such as disk read and write
operations.

Syntax

    BREAK [ON|OFF]

To display the current BREAK setting at the command prompt, use the
following syntax:

    BREAK

In your CONFIG.SYS file, use the following syntax:

    BREAK=ON|OFF

Parameter

ON|OFF
    Turns extended CTRL+C checking on or off.


BUFFERS/BUFFERSHIGH
===================

Allocates memory for a specified number of disk buffers when your system
starts. Use the BUFFERSHIGH command to load the buffers in the upper
memory area. You can use these commands only in your Config.sys file.

Syntax

    BUFFERS=n[,m]
    BUFFERSHIGH=n[,m]

Parameters

n
    Specifies the number of disk buffers. The value of n must be in the
    range 1 through 99.  The default is 30.

m
    Specifies the number of buffers in the secondary buffer cache. The value
    of m must be in the range 0 through 8.  The default is 0 (no secondary
    cache buffers).

If you specify an invalid value for n or m, BUFFERs uses the default 
settings.


COUNTRY
========

Enables MS-DOS to use country-specific conventions for displaying times,
dates, and currency; for determining the order by which characters are
sorted; and for determining which characters can be used in filenames. You 
can use this command only in your Config.sys file.

The COUNTRY command configures MS-DOS to recognize the character set and
punctuation conventions observed when using one of the supported languages.

Syntax

    COUNTRY=xxx[,[yyy][,[drive:][path]filename]]

Parameters

xxx
    Specifies the country code.

yyy
    Specifies the character set for the country.

[drive:][path]filename
    Specifies the location and name of the file containing country
    information.


DEVICE
======

Loads into memory the device driver you specify. You can use this command
only in your Config.sys file.

Syntax

    DEVICE=[drive:][path]filename [dd-parameters]

Parameters

[drive:][path]filename
    Specifies the location and name of the device driver you want to load.

[dd-parameters]
    Specifies any command-line information required by the device driver.


DEVICEHIGH
==========

Loads a device driver you specify into the upper memory area. Loading a 
device driver into the upper memory area frees more bytes of conventional 
memory for other programs. If upper memory is not available, the DEVICEHIGH 
command functions just like the DEVICE command.

You can use this command only in your Config.sys file.

Syntax

    DEVICEHIGH [drive:][path]filename [dd-parameters]

To specify the region(s) of memory into which to load the device driver, use
the following syntax:

    DEVICEHIGH [[/L:region1[,minsize1][;region2[,minsize2] [/S]]=
    [drive:][path]filename [dd-parameters]

Parameters

[drive:][path]filename
    Specifies the location and name of the device driver you want to load
    into the upper memory area.

dd-parameters
    Specifies any command-line information required by the device driver.

Switches

/L:region1[,minsize1][;region2[,minsize2]...
    Specifies one or more regions of memory into which to load the device
    driver. By default, MS-DOS loads the driver into the largest free
    upper memory block (UMB) and makes all other UMBs available for the
    driver's use. You can use the /L switch to load the device driver into a
    specific region of memory or to specify which region(s) the driver can
    use.

    To load the driver into the largest block in a specific region of upper
    memory, specify the region number after the /L switch. For example, to
    load the driver into the largest free block in region 4, you would type
    /L:4. (To list the free areas of memory, type MEM /F at the command
    prompt.)

    When loaded with the /L switch, a device driver can use only the
    specified memory region. Some device drivers use more than one area of
    memory; for those drivers, you can specify more than one region. (To
    find out how a particular device driver uses memory, issue the MEM /M
    command and specify the device-driver name as an argument.) To specify
    two or more regions, separate the block numbers with a semicolon (;).
    For example, to use blocks 2 and 3, you would type /L:2;3.

    Typically, MS-DOS loads a driver into a UMB in the specified region
    only if that region contains a UMB larger than the driver's load size
    (usually equal to the size of the executable program file). If the
    driver requires more memory while running than it does when loaded, you
    can use the minsize parameter to ensure that the driver will not be
    loaded into a UMB that is too small for it. If you specify a value for
    minsize, MS-DOS loads the driver into that region only if it contains a
    UMB that is larger than both the driver's load size and the minsize
    value.

/S
    Shrinks the UMB to its minimum size while the driver is loading. Using
    this switch makes the most efficient use of memory. This switch is
    generally used only by the MemMaker program, which can analyze a device
    driver's memory use to determine whether the /S switch can safely be
    used when loading that driver. This switch can be used only in
    conjunction with the /L switch and affects only UMBs for which a 
    minimum size was specified.


DOS
====

Specifies that MS-DOS should maintain a link to the upper memory area, load
part of itself into the high memory area (HMA), or both. You can use this
command only in your Config.sys file.

Syntax

    DOS=HIGH|LOW[,UMB|,NOUMB][,AUTO|,NOAUTO]

    DOS=[HIGH,|LOW,]UMB|NOUMB[,AUTO|,NOAUTO]
  
    DOS=[HIGH,|LOW,][UMB,|NOUMB,]AUTO|NOAUTO

Parameters

UMB|NOUMB
    Specifies whether MS-DOS should manage upper memory blocks (UMBs)
    created by a UMB provider such as Emm386.exe. The UMB parameter
    specifies that MS-DOS should manage UMBs, if they exist. The NOUMB
    parameter specifies that MS-DOS should not manage UMBs. The default
    setting is NOUMB.

HIGH|LOW
    Specifies whether MS-DOS should attempt to load a part of itself into
    the HMA (HIGH) or keep all of MS-DOS in conventional memory (LOW). The
    default setting is LOW.

AUTO|NOAUTO
    Specifies whether MS-DOS should automatically load Himem.sys, Ifshlp.sys,
    Dblbuff.sys, and Setver.exe device drivers if they are not explicitly
    loaded in your Config.sys file. The default setting, AUTO, automatically
    loads these device drivers. The AUTO setting also automatically uses
    the BUFFERSHIGH, FILESHIGH, FCBSHIGH, LASTDRIVEHIGH, and STACKSHIGH
    commands, whether the -HIGH form of the command was used or not. If
    you specify the NOAUTO parameter, you must explicitly load these device
    drivers and explicitly use the -HIGH form of the above commands in order
    to take advantage of them.


DRIVPARM
========

Defines parameters for devices such as disk and tape drives when you start
MS-DOS. You can use this command only in your Config.sys file.

The DRIVPARM command modifies the parameters of an existing physical drive.
It does not create a new logical drive. The settings specified in the
DRIVPARM command override the driver definitions for any previous block
device.

Syntax

    DRIVPARM=/D:number [/C] [/F:factor] [/H:heads] [/I] [/N] [/S:sectors]
    [/T:tracks]

Switches

/D:number
    Specifies the physical drive number. Values for number must be in the
    range 0 through 255 (for example, drive number 0 = drive A, 1 = drive B,
    2 = drive C, and so on).

/C
    Specifies that the drive can detect whether the drive door is closed.

/F:factor
    Specifies the drive type. The following table shows the valid values for
    factor and a brief description of each. The default value is 2.

    0        160K/180K or 320K/360K

    1        1.2 megabyte (MB)

    2        720K (3.5-inch disk)

    5        Hard disk

    6        Tape

    7        1.44 MB (3.5-inch disk)

    8        Read/write optical disk

    9        2.88 MB (3.5-inch disk)

/H:heads
    Specifies the maximum number of heads. Values for heads must be in the
    range 1 through 99. The default value depends on the value you specify
    for /F:factor.

/I
    Specifies an electronically compatible 3.5-inch floppy disk drive.
    (Electronically compatible drives are installed on your computer and use
    your existing floppy disk drive controller.) Use the /I switch if your
    computer's ROM BIOS does not support 3.5-inch floppy disk drives.

/N
    Specifies a nonremovable block device.

/S:sectors
    Specifies the number of sectors per track that the block device
    supports. Values for sectors must be in the range 1 through 99. The
    default value depends on the value you specify for /F:factor.

/T:tracks
    Specifies the number of tracks per side that the block device supports.
    The default value depends on the value you specify for /F:factor.


FCBS, FCBSHIGH
==============

Specifies the number of file control blocks (FCBs) that MS-DOS can have open
at the same time. Use the FCBSHIGH command to load the FCBs in the upper
memory area. You can use these commands only in your Config.sys file.

A file control block is a data structure that stores information about a
file.

Syntax

    FCBS=x
    FCBSHIGH=x

Parameter

x
    Specifies the number of file control blocks that MS-DOS can have open at
    one time. Valid values for x are in the range 1 through 255. The default
    value is 4.


FILES/FILESHIGH
===============

Specifies the number of files that MS-DOS can access at one time. Use the 
FILESHIGH command to load the command in the upper memory area. You can 
use these commands only in your Config.sys file.

Syntax

    FILES=x
    FILESHIGH=x

Parameter

x
    Specifies the number of files that MS-DOS can access at one time. Valid
    values for x are in the range 8 through 255. The default value is 8.


INSTALL/INSTALLHIGH
====================

Loads a memory-resident program into memory when you start MS-DOS. Use the 
INSTALLHIGH command to load the memory-resident program into the upper
memory area. You can use these commands only in your Config.sys file.

Memory-resident programs stay in memory as long as your computer is on. They
can be used even when other programs are active. You can use the INSTALL
or INSTALLHIGH command to load MS-DOS memory-resident programs--for example, 
Fastopen, Keyb, Nlsfunc, and Share.

Syntax

    INSTALL=[drive:][path]filename [command-parameters]
    INSTALLHIGH=[drive:][path]filename [command-parameters]

Parameters

[drive:][path]filename
    Specifies the location and name of the memory-resident program you want
    to run.

command-parameters
    Specifies parameters for the program you specify for filename.


LASTDRIVE/LASTDRIVEHIGH
=======================

Specifies the maximum number of drives you can access. Use the 
LASTDRIVEHIGH command to load the LASTDRIVE data structures in the upper 
memory area. You can use these commands only in your Config.sys file.

The value you specify represents the last valid drive that MS-DOS is to
recognize.

Syntax

    LASTDRIVE=x
    LASTDRIVEHIGH=x

Parameter

x
    Specifies a drive letter in the range A through Z.


NUMLOCK
========

Specifies whether the NUM LOCK key is set to ON or OFF when your computer
starts. You can use this command only in your Config.sys file.

Syntax

    NUMLOCK=[ON|OFF]

Parameters

ON|OFF
    If set to ON, turns on the NUM LOCK key when MS-DOS displays the startup
    menu. If set to OFF, turns NUM LOCK off.


REM
===

Enables you to include comments in a batch file or in your Config.sys file.
The REM command is also useful for disabling commands. You can use a
semicolon (;) instead of the REM command in your Config.sys file, but not in
batch files.

Syntax

    REM [string]

Parameters

string
    Specifies any string of characters -- the command you want to disable or
    the comment you want to include.


SET
===

Displays, sets, or removes MS-DOS environment variables.

You use environment variables to control the behavior of some batch files
and programs and to control the way MS-DOS appears and works. The SET
command is often used in the Autoexec.bat or Config.sys files to set
environment variables each time you start MS-DOS.

Syntax

    SET variable=[string]

To display the current environment settings at the command prompt, use the
following syntax:

    SET

Parameters

variable
    Specifies the variable you want to set or modify.

string
    Specifies the string you want to associate with the specified variable.


SHELL
=====

Specifies the name and location of the command interpreter you want MS-DOS
to use. You can use this command only in your Config.sys file.

If you want to use your own command interpreter (instead of Command.com),
you can specify its name by adding a SHELL command to your Config.sys file.

Syntax

    SHELL=[[drive:]path]filename [parameters]

Parameters

[[drive:]path]filename
    Specifies the location and name of the command interpreter you want
    MS-DOS to use.

parameters
    Specifies any command-line parameters or switches that can be used with
    the specified command interpreter.


STACKS/STACKSHIGH
=================

Supports the dynamic use of data stacks to handle hardware interrupts. Use 
the STACKSHIGH command to load the stacks in the upper memory area. You 
can use these commands only in your Config.sys file.

Syntax

    STACKS=n,s
    STACKSHIGH=n,s

Parameters

n
    Specifies the number of stacks. Valid values for n are 0 and numbers in
    the range 8 through 64.

s
    Specifies the size (in bytes) of each stack. Valid values for s are 0
    and numbers in the range 32 through 512.


SWITCHES
=========

Specifies special options in MS-DOS. Use this command only in your
Config.sys file.

Syntax

    SWITCHES= /F /K /N /E[:n]

Switches

/F
    Skips the two-second delay after displaying the "Starting MS-DOS"
    message during startup.

/K
    Forces an enhanced keyboard to behave like a conventional keyboard.

/N
    Prevents you from using the F5 or F8 key to bypass startup commands.
    (SWITCHES /N does not prevent you from pressing CTRL+F5 or CTRL+F8 to
    bypass Drvspace.bin or Dblspace.bin; to prevent this, use the D**SPACE /SWITCHES
    command to add the SWITCHES /N setting to your D**space.ini file.)

/E[:n]
    Used without the :n parameter, indicates that Io.sys should suppress
    the automatic relocation of EBIOS. (Automatic relocation of EBIOS
    increases the conventional memory available to MS-DOS-based programs.)
    Supressing automatic relocation results in less conventional memory 
    available to MS-DOS-based programs. Use the /E switch with the n 
    parameter to relocate N bytes of EBIOS to low memory, where n is 
    the number of bytes to be relocated. The minimum value for n is 48 and 
    the maximum value is 1024. The number specified is always rounded up to 
    the next multiple of 16.

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