Module 1: Operating system basics
Configuring DOS

MS-DOS System Files
We use the phrase "legacy operating system files" to refer to MS-DOS and Windows 3.x operating system files. MS-DOS is not commonly used by itself today, it still can be accessed from every version of Microsoft Windows by clicking Start / Run and typing "command" or by typing "CMD" in Windows NT, Windows 2000 or Windows XP.

MS-DOS is not an overly complex operating system. In most situations, you need to keep track of only a few operating system files.

An MS-DOS system can start up without a Config.sys or an Autoexec.bat file. However, if the files are present,
MS-DOS will attempt to process the files during startup.

MS-DOS Operating System Files
IO.SYS
MSDOS.SYS
COMMAND.COM
HIMEM.SYS
EMM386.SYS
CONFIG.SYS
AUTOEXEC.BAT

MS-DOS Startup
The startup process for an MS-DOS system is the same whether you boot from diskette or a hard disk drive.

During the boot process:

• The system will run its power-on self test (POST) and the BIOS will attempt to locate the operating system files.
• The system will use the Master Boot Record (MBR) to identify the active partition and load the initial MS-DOS boot files.
• Io.sys will load into memory and remain memory-resident.
• The Io.sys file will locate, load, and interpret the Config.sys file.
• Msdos.sys will load into memory and remain memory-resident.
• Command.com will load and a portion of Command.com will remain memory-resident.
• Command.com will attempt to locate, load and execute the Autoexec.bat file.
• A command prompt displays and the system is ready for use.

Windows 3.x System Files
In addition, Windows 3.x will load dynamic link library (DLL) files, font files, program group files and other support files during startup.

WIN.COM
KRNL286.EXE, KERNEL386.EXE
USER.EXE
GDI.EXE
INITIALIZATION FILES

WINDOWS 3.x Startup
Windows 3.x startup is initiated by executing Win.com.
This command can be executed from a command prompt, but is more commonly included in the Autoexec.bat file so that Windows 3.x loads automatically.

Win.com will verify the system environment, then select and load a kernel file (Krnl286.exe or Krnl386.exe), User.exe and Gdi.exe.

The system initialization files will be loaded and processed to configure the Windows 3.x operating environment.

Other components files, such as the program group files and font files, will be loaded and the desktop initialized.

By default, the user will be returned to the MS-DOS command prompt after exiting Windows 3.x.

Introduction to Windows 98 NEXT...

Practical Work

Configuring DOS

• DOS Editor
• Configuration files
  • CONFIG.SYS
  • AUTOEXEC.BAT

Navigating DOS

• The directory structure
• The default drive
  • Changing the default drive
• Directories and the DOS prompt
  • Changing the current directory (CD)
• Getting system information
  • Displaying the directory structure (TREE)
  • Listing files and directories (DIR)
  • Obtaining the version
• Getting memory and program information
  • MEM

  • MEM /C

DOS file management

• Copying and moving files
• Copying directory structures
• Renaming a file (REN)
• Deleting a file (DEL)
• Creating a directory
• Removing a directory

Configuring DOS drivers

Introduction to Windows 98 NEXT...