CONFIG.SYS

(redirected from CONFIG.NT)

CONFIG.SYS

(operating system)
A text file containing special system configuration commands. It is found in the root directory on an MS-DOS computer, typically on drive C (the hard disk). It is read by MS-DOS at boot time, after the setup has been read from CMOS RAM and before running AUTOEXEC.BAT. It can be modified by the user.

Some example commands which CONFIG.SYS might contain are:

DEVICE=C:\DOS\HIMEM.SYS /testmem:off

Load the extended memory manager.

DEVICE=C:\DOS\EMM386.EXE RAM

Load the expanded memory manager.

BUFFERS=10,0

Specify memory for disk buffers.

FILES=70

Set the number of files that can be open at once.

DOS=UMB

DOS is located in UppeMemoryBlock.

LASTDRIVE=Z

Disk drives are A: to Z:.

FCBS=16,0

Set the number of file control blocks.

DEVICEHIGH /L:1,12048 =C:\DOS\SETVER.EXE

Report the DOS version to older programs.

DOS=HIGH

DOS should maintain a link to UMB.

COUNTRY=358,437 C:\DOS\COUNTRY.SYS

Set the country code for some programs.

STACKS=9,256

Set dynamic stacks for hardware control.

SHELL=C:\DOS\COMMAND.COM C:\DOS\ /E:1024 /p

Set the location of the command interpreter.

CONFIG.SYS

(CONFIGure SYStem) A text file that contained commands to load drivers and establish settings in a DOS PC. Along with AUTOEXEC.BAT, it resided in the root folder. CONFIG.SYS was included in Windows versions for DOS compatibility and was replaced with CONFIG.NT in 32-bit versions of Windows starting with Windows NT. Users could easily make changes, and installation programs sometimes modified CONFIG.SYS for their own purposes.

The following CONFIG.SYS example primarily loads memory managers that were essential to squeeze programs into every byte of what little RAM there was at the time. See AUTOEXEC.BAT, UMA, HIMEM.SYS and EMM386.EXE.
 Driverdevice=c:\dos\himem.sys       RAM > 1MB
 device=c:\dos\emm386.exe ram  EMS memory
 device=c:\dos\ansi.sys        screen/KB
 device=c:\mouse\mouse.sys     mouse
 files=30buffers=40dos=high,umb