1. Command Line Interface

2. Lecture Objectives Explain the operation of the command line interface
Execute fundamental commands from the command line interface
Manipulate files and folders from the command line

3. How does the Command Line Work?
Similar to Instant Message conversation with computer
The prompt indicates that the computer is ready to receive a command
Command is typed and ENTER is pressed
PC executes command
Prompt is displayed, indicating that the computer is waiting for the next command
Explain to students that executing commands from the command line, affects files and folders as viewed from the Windows GUI.
Explain that DIR will display the contents of a folder same as double clicking that folder in Windows.

4. Accessing the Command Line
Run dialog box
Start menu under Programs | Accessories
Win 9x/Me link is named MS-DOS prompt
Win NT, 2000, XP link is called Command Prompt
To close command line interface
Type Exit at command line and press enter
Close the window

5. Command Prompt VERY IMPORTANT:
The command prompt is always focused on a specific folder.
Any commands executed are performed on the files in the folder on which the prompt is focused.
Examples: C:\> root directory of C: drive
C:\Diploma\APLUS>
You must focus the prompt on the drive and folder where you want to work

6. Filenames and File Formats
In Windows, each program and piece of data is stored as an individual file
Each file has a name, stored with the file on the drive
Names have 2 parts: filename and extension

7. Eight-dot-Three naming system
File name cannot be more that 8 chrs
Extension can be up to 3 chrs, OPTIONAL
Following chrs cannot be used in filename or extension:
/ \ [ ] | = + ; , * ? And division symbol
Acceptable: FRED.EXE, SYSTEM.INI, FILE1.DOC, DRIVER3.SYS, JANET, CODE33.H
Unacceptable: 4CHAREXT.EXEC, WAYTOOLONG.FIL, BAD/CHAR.BAT, .NO

8. Windows naming rules
All versions starting with Win 9x are not limited be 8.3
Filenames up to 255 chrs
Win 9x has backward compatibility with DOS by creating 2 names for every file, 8.3 name and a long file name if necessary

9. File extensions Describes the type or function of the file
COM = command, EXE = executable
Anything that is not a program is a data file used by a program
Extension of a data file indicates which program uses that data file
.DOC = MSWord, .PPT = PowerPoint
Graphic file extensions represent the graphic standard used to create the image
.JPEG =Joint Photographic Experts Group

10. File Formats All files stored on hard drive in binary format
Every program is unique in the way it reads and writes this binary data
Each unique way of binary organization is known as a file format
One program cannot read another programs files unless it can convert the other programs format
When DOS was introduced, no programs were available to convert format so that files can be exchanged.
Common format was developed that any program could read ASCII (American Standard Code for Information Interchange)
ASCII was the first universal file format
All programs can read simple text files

11. Drives and Folders
To execute commands from the command line, must focus the prompt at the specific drive and folder that contains the files or program with which you want to work
At boot, Win assigns letters to drives and drive partitions
1st floppy is A:, 2nd floppy is B:, hard drive is C:, other optical drives are assigned letters sequentially after the hard drive
Win 2000, NT, XP allows you to change the default lettering of dirves

12. Hierarchical Directory Tree
All files are put in groups called folders
Any file not in a folder within the tree is said to be in the root directory
A folder inside another folder is called a subfolder
Any folder can have multiple subfolders
Windows uses hierarchical directory tree to organize contents of drives. Roots and branches
2 or more files with the same name can exist in different folder but 2 files in the same folder cannot have the same name. Same for subfolders.

13. Hierarchical Directory Tree
Hard drive is represented by C:
Root directory is indicated by \, C:\
Subdirectories/Subfolders are indicated by adding \ and the directory name
Exact location of a file is known as its PATH
To focus on the directory TEST under the root directory of the C drive: C:\TEST
To focus on subdirectory SYSTEM: C:\TEST\SYSTEM
If there is a file called TEST2.TXT in SYSTEM subdirectory, location of this file would be C:\TEST\SYSTEM\TEST2.TXT
Examples of paths: C:\DOS, F:\FRUSCH3\CLEAR, A:\REPORTS, D:\

14. Fundamental Commands
ALL commands use similar structure and execute in the same way
Name of command , target of command followed by any switches (extra numbers or letters at the end)
Typing the command followed /? Displays help menu describing syntax and possible switches
We will examine 4 commands available in all versions of Microsoft’s command line interface: DIR, CD, MD, RD

15. DIR Command Contents of the directory where the prompt is focused
Lists the following:
Filename
Extension
File size in bytes
Creation date/time
DIR/W command shows you only the file names
DIR/? Shows the help menu

16. CD Command (Directories)
Change focus of command prompt to a different directory
CD\ followed by directory name
If directory does not exist, error message
Invalid Directory
The system cannot find the path specified
Return to root directory by typing CD\
Alternatively u can use a space instead of \ after CD
Jump multiple directories C:\>CD FRED\BACKUP\TEST (C:\FRED\BACKUP\TEST>)
Go up one level CD..

17. Moving Between Directories
CD NOT used to move between drives
Type drive letter followed by colon
If drive does not exist:
Invalid drive specification
The system cannot find the specified drive
Using DIR, CD, and drive letter commands you can access any folder on any storage device on PC

18. Making Directories To make a directory
To make a directory called QUAKE3 under root directory: C:\>MD QUAKE3, press ENTER
If command is successfully executed, the command prompt will be displayed
Use DIR to verify that directory was created

19. Removing Directories Reverse of MD
Go to directory that contains the subdirectory you want to delete
Execute RD command
RD will not delete directory if it contains subdirectories or files
Must delete the files (DEL) and remove subdirectories (RD) before you can remove a directory
DELTREE command deletes the directory as well as all subdirectories and files

20. Running a Program
Change focus of prompt to the folder where program is located
Type name of program
Press ENTER
Go to C:\WINDOWS\System32
Type DIR
Identify file MEM.EXE
Type MEM and enter

21. Working with Files All files have 4 basic attributes:
Hidden
Read-only
System
Archive
Refer to photocopy for specific example of attribute command
Hidden files not displayed using DIR command
Read-only file cannot be modified or deleted
System attribute identifies a a system file e.g. IO.SYS
Archive allows back up software to identify files that have been changed since their last backup

22. Renaming Files
REN or RENAME command (refer to photocopy for example)

23. Delete Files Use DEL command Careful! No recycle bin.
Erased file can only be recovered using Norton Unerase
Can delete multiple files using wild cards

24. Copying and Moving Files
Focus prompt on directory containing the file or folder to be copied
Type COPY or MOVE and a space
Type name(s) of the file(s) to be copied/moved and a space
Type the path of new location for the files (Refer to example on photocopy)

25. The Software Core

26. A Short History of MS-DOS

27. Understanding DOS All versions were built for a specific class of CPU.
MS-DOS never overcame critical limitations.
All versions used a command-line interface.
You must use the DOS prompt to set up a new system or hard disk drive.

28. DOS Boot Sequence and Files
Three core programs
IO.SYS
MSDOS.SYS
COMMAND.COM
Two optional startup files
CONFIG.SYS
AUTOEXEC.BAT

29. Summary of Steps in Booting the System
The power-on self test (POST) runs and invokes the operating system (OS).
The read-only memory basic input/output system (ROM BIOS) looks for an OS and checks for IO.SYS and MSDOS.SYS.
The OS processes CONFIG.SYS, if present.
COMMAND.COM is loaded.
The OS processes AUTOEXEC.BAT, if present.
COMMAND.COM presents the active-drive prompt.

30. The DOS File System The file is the primary unit of data storage.
Files are organized into directories.
File and directory names can be up to eight characters long, followed by a period and a three-character extension.
Some universal extensions are .exe, .com, .sys, .bat, .txt, .doc, and .drv.
File and directory names are not case-sensitive.

31. The Evolution of Microsoft Windows
Early versions presented a graphical user interface (GUI) for MS-DOS.
Microsoft Windows 3.11 was the last 16-bit OS and the most well known version.
Microsoft Windows 95 was the first 32-bit version.
All applications designed for Windows have standard interfaces.
Multitasking allows users to have more than one application open.

32. Operating Modes
Real mode could address only 1 MB of random access memory (RAM).
Standard mode allowed programs to run in protected mode.
In protected mode, programs could address up to 16 MB of RAM.
386 enhanced mode could address up to GB of RAM.
Certain applications included a Windows runtime version.

33. Windows Resource Management

34. Memory Paging and Virtual Machines
Virtual memory is an area on the hard disk drive (called a swap file) that the system uses to store program code temporarily.
Virtual machines (VMs) allow multiple programs to operate.
DOS programs run individually in separate VMs.

35. Windows Operating Systems
Microsoft Windows for Workgroups 3.11 is an upgrade to Microsoft Windows 3.1.
Windows 95, Microsoft Windows 98, and Microsoft Windows Me can be networked easily.
Microsoft Windows NT is designed for networking.
Microsoft Windows 2000 replaces Windows NT.
Upgrading to Windows NT or Windows 2000 could present compatibility problems with some hardware and applications.

36. The COMMAND Command
MS-DOS uses a text-based command-line user interface.
A text-based interface requires no drivers because display functions are built in.
COMMAND.COM provides the user interface.

37. Working with the Prompt
Typing PROMPT /? or HELP PROMPT provides help information.
DOS HELP returns information on customizing the prompt and the information that appears.

38. Internal and External Commands
External commands exist as separate files.
Windows has its own set of system utilities.
Internal commands are contained within COMMAND.COM.
Command mode requires typing a command instead of clicking an icon.

39. DOS Mode Navigation and File Management
The DOS file system uses a tree structure.
A fully qualified path is the list of directories from the root to the file.
The DIR command displays the contents of the current or a specified directory.
DOS does not support Windows long filenames.
The MD command creates a new directory.

40. The PATH Command
PATH allows you to display and change the search path.
%PATH% appends the old path to the new path.
Programs in path directories can be run from any location on the computer.

41. Creating a Batch File
A batch file is an executable file that runs a series of existing commands or applications.
Commands listed in the file are executed in sequence.
Any executable that can be run from the prompt can be included in a batch file.

42. Renaming a File The RENAME or REN command allows you to rename a file.
The CD command allows you to change directories.
The CLS command clears the screen.

43. Using Edit

44. Summary of DOS Terminology

45. CONFIG.SYS Commands BUFFERS COUNTRY DEVICE DEVICEHIGH DOS FCBS FILES
INSTALL
LASTDRIVE
MOUSE.SYS
NUMLOCK
SHELL
SWITCHES

46. AUTOEXEC.BAT Commands DOSKEY ECHO KEYB MOUSE.EXE PATH PAUSE PROMPT SET
SHARE
SMARTDRV

47. File System Basics
The file system organizes data on the storage medium.
Different media require different file systems.
File systems define naming conventions, file size, and media capacity.
Magnetic media employ several different file systems, depending on the OS.

48. Key File System Terms Block Boot disk Boot sector Cluster Dual boot
Encryption
End-of-file (EOF) marker
File
File allocation table (FAT)
File format
File handle
File locking
Filename
Folder
Format
Low-level format
Master boot record
Partition table
Primary partition
Sector
Track
Volume

49. Comparing and Choosing File Systems
Decision factors:
Dual boot requirement
Number and size of hard disk drives
Size of partitions
Need to support legacy applications
Need for advanced features such as security

50. FAT-Based File Systems
All modern PCs can use FAT.
FAT organizes files by listing them in a table.
Two copies of the table are maintained on the media.
FAT was developed for and is still used by floppy disk drives.
There are three versions: FAT12, FAT16, and FAT32.

51. FAT16 and FAT32 Compared and Contrasted
High compatibility
Use of MS-DOS bootable floppy disk
Performance advantage on small volumes
Manual intervention to use FAT copy
No backup of boot sector
2-GB volume limit
Better performance when operating in real mode or safe mode
Dual boot with Windows NT and Windows 98
8.3 filenaming limit
Limited compatibility
No use of MS-DOS bootable floppy disk
More efficient allocation of disk space
Automatic use of FAT copy if needed
Automatic backup of boot sector
Support of 32-GB volumes
Faster load times for applications and large data files
No dual boot with Windows NT and Windows 98
Support of filenames up to 255 characters

52. The NT File System (NTFS)
Was introduced with Windows NT
Supports long filenames and is optimized for multiuser environments
Provides file and folder level security
Is more reliable than previous file systems
Is not completely supported under Windows NT

53. Advantages and Disadvantages of NTFS
Supports volumes up to terabytes (TB)
Maintains a recovery log
Has no limit on number of entries at root
Allows faster file access
Supports disk quotas (Windows 2000)
Supports file and folder compression
Supports file and folder security
Does not allow accessing NTFS volumes under MS-DOS, Windows 95, or Windows 98
Does not allow using NTFS volumes as a primary partition for dual booting MS-DOS, Windows 95, or Windows 98
Could decrease performance on volumes smaller than 400 MB

54. File System Size Limitations
Different OSs handle cluster size differently.
Under FAT volumes, drives smaller than MB are formatted as FAT12.
MS-DOS, Windows 95, and Windows 98 cannot access FAT16 volumes larger than GB.

55. File System Security FAT attributes on FAT file systems
FAT has attributes that can protect files from being overwritten or viewed.
Attributes can be set by using the ATTRIB DOS-mode command, or by right-clicking a file in Windows and selecting the Properties option.
NTFS file and folder security
NTFS uses permissions to determine who can access the file or folder.
Permissions are set by using the Security tab for the file or folder.

56. Chapter Summary
An OS is the interface between the hardware and the user.
All OSs have a user interface, memory, and file management.
Technicians need to know how to perform command prompt operations.
Technicians who work with older OSs must understand MS-DOS and DOS startup files.
Internal and external commands can be used to configure and troubleshoot.
FAT32 has several enhancements over FAT16.
NTFS supports file and folder security, compression, and disk quotas.