DOS System File: CONFIG.SYS

2008 Oct 18

DOS not process CONFIG.SYS lines in order, e.g.
it processes lines with DOS=, FILE=, and BUFFERS=
before processing DEVICE= and DEVICEHIGH= lines.

**CONFIG.SYS Commands**
BREAK=	Turns on or off extended Ctrl+Break checking
BUFFERS=	Sets the number of disk buffers used by DOS
COUNTRY=	Sets country name
DEVICE=	Loads an installable driver
DEVICEHIGH=	Loads an installable device driver into high (UMB) memory
DOS=	Sets whether DOS loads into conventional memory or into the high memory area (HMA)
DRIVPARM=	Redefines the physical characteristics of an existing drive
FCBS=	Sets the maximum number of open file control blocks (FCBs)
FILES=	Sets the maximum number of open files that DOS will allow
INCLUDE=	Includes the commands from one CONFIG.SYS block within another
INSTALL=	Loads TSR programs into memory
LASTDRIVE=	Sets the maximum number of drive letters available to DOS
MENUCOLOR=	Sets the color of the screen for the CONFIG.SYS startup menu
MENUDEFAULT=	Sest the default menu choice in a CONFIG.SYS menu block
MENUITEM=	Sest the text and configuration block associated with menu items in CONFIG.SYS
NUMLOCK=	Sets the of the NumLock state when the computer starts up
REM	Inserts a remark into CONFIG.SYS
SET	Sets environment variables
SHELL=	Sets the name of the program used as a command-line shell by DOS
STACKS=	Sets the number of stacks set aside for hardware interrupts
SUBMENU=	Defines a submenu in CONFIG.SYS
SWITCHES=	Sest miscellaneous options for DOS

CONFIG.SYS Device= *Drivers*
ANSI.SYS	Alternate console driver, which provides ANSI standard control of the display and keyboard
DBLSPACE.SYS	Dummy drivers that can relocate DBLSPAVE.BIN in memory
DISPLAY.SYS	Device driver for the display with international code page support
DRIVER.SYS	Driver that sets the DOS drive letter for an existing disk drive or creates and additional drive letter for a disk drive
EMM386.SYS	Expanded (EMS0 Memory Manager with upper memory block (UMB) support
HIMEM.SYS	Extended (XMS) Memory Manager
INTERLNK.EXE	Client device driver for an InterLnk network
INTESVR.EXE	Server program for an InterLnk network
POWER.EXE	Advanced Power Management (APM) device driver for portable computers
RAMDRIVE.SYS	Driver that sets up a disk drive in RAM memory
SETVER.EXE	DOS version control program that can fool certain programs into running with the "incorrect" version of DOS
SMARTDRV.EXE	Driver that installs double-buffering to make SMARTDrive compatible with certain hard disk drives

More drivers may exist than listed above.

**CONFIG.SYS Options**
Option	DOS VER	Syntax
*Comment*	6.0 ...	;comment text Everything from the ; to end of line to be ignored
*Prompt*	6.0 ...	command?=settings command : any CONFIG.SYS command that uses command= settings : the setting for command= DOS prompts for confirmation before executing command. Consider using menus if there are many prompts. No spaces are allowed before the ?, or after unless switches come first, e.g. DEVICEHIGH?=C:\DOS\RAMDRIVE.SYS 2000 512 225 /G DEVICEHIGH? /L:1,1200 /S =C:\DOS\RAMDRIVE.SYS 2000 512 225 /G Pressing the F8 key when DOS is displays: Starting MS-DOS... (its startup message) causes DOS to prompt for every line, with or without a ?.
*[BLOCKS]*	6.0 ...	[BLOCKNAME] Allows for multiple configurations and menu executions starting a computer. A block name can be up to 70 characters long. [BLOCKNAME] must be on a line by itself. Nesting if blocks is not allowed. Legal characters are same as filename characters (no spaces). Commands in a [COMMON] block are always executed by DOS. [COMMON] blocks can appear multiple times in CONFIG.SYS and is the only block allowed to do so. A [COMMON] block before the [MENU] block is executed before the [MENU] block. A [COMMON] block at the end of CONFIG.SYS is always executed last. Always include a [COMMON] block at the end of CONFIG.SYS so that any lines added by installation software will be executed, no matter which configuration is selected. Without [COMMON] any added lines will belong to the last [BLOCK] and may not be executed. Any commands before a block name are considered to be in [COMMON] and are executed first. The [MENU] block defines entries for the main startup menu and contains the configuartion menu for DOS to dsiplay when the computer starts. DOS always executes this block. Any block not referred to by a MENUITEM= line is not executed by DOS except for the predefined block names [MENU] and [COMMON].

2005-2008