Seminar/Training of Group 1

2. Seminar/Training of Group1 MS-DOS (Microsoft Disk Operating System)

3. MS-DOS HistoryThe history of MS-DOS is surprisingly long. It started off as QDOS (Quick and Dirty Operating System) which was developed by Seattle Computer Products to run on IBM's new PC. This list is fairly comprehensive although a number of the more obscure versions of DOS have been omitted.

6. What is DOS? DOS stands for Disk Operating System. DOS controls the computer’s hardware and provides an environment for programs to run. This system program must always be present when working with your computer.

7. When IBM entered the personal computer marketplace in the fall of 1981, responsibility for creating an operating system was subcontracted to a brand new company named Microsoft. The result, MS-DOS was a command-driven operating system that allowed users to issue cryptic, single-line commands through a command interface. MS-DOS quickly became an industry standard and established the financial base on which Bill Gates and Paul Allen built today’s Microsoft. Given the availability of Windows and other easier to use interfaces, MS-DOS is rarely used today, however. Why then bother to learn MS-DOS commands? Basically there are two reasons: Windows and other, more sophisticated operating systems sometimes do a bit too much for the user, effectively hiding what is really happening in windows. Should your computer fail or become infected with a virus, many utility and virus protection programs include a special recovery diskette. Often, the recovery diskette is designed to boot to MS-DOS and uses MS-DOS commands to support the recovery process.

8. 3. The default drive and the system prompt are displayed by the operating system. The user responds by typing a command name followed by necessary parameters. A delimiter, usually a space, separates the command from the parameters and (if there are several) the parameters from each other. Why You Need DOS There are a variety of reasons why you need DOS. A few of them are listed below to satisfy your curiosity. 1. DOS controls the flow of information between you and the computer (translator). 2. DOS allows you to store information on your computer. 3. DOS allows you to retrieve information stored on your computer. 4. DOS interprets and translates the software you have on your computer. 5. DOS gives you access to all its function (i.e. saving, copying, and printing files).

9. Installing MS-DOS When installing MS-DOS, make sure that in the BIOS the the boot disk is set to A: first, then the hard drive (boot sequence: A:, C:) Then insert disk 1 in the A: drive, power up the computer, then follow the on-screen instructions. You must enter the following information: * time and date * country * the media on which to install the operating system (make sure the drive is accessible and has sufficient free disk space) * the storage folder for MS-DOS files * if the MS-DOS shell should appear on each start-up * if MS-DOS should occupy a single partition taking up the entire hard drive

10. The Chapter Tutorial The introduction to MS-DOS is presented as a tutorial. Do not simply read it. Instead, find a personal computer that runs Windows. MS-DOS error messages tend to be rather cryptic and not very useful. Common mistakes include misspelling a command or file name, failing to type a space between a command and its parameters or between parameters, and adding extra, unnecessary parameters. If you type a command, press enter, and see an error message, simply retype the command after the next MS-DOS prompt. The easiest and safest way to access MS-DOS through Microsoft Windows is to select the MS-DOS Prompt from the programs menu. Click on the Start button. Then move the mouse pointer to Programs. You should find an entry labeled MS-DOS Prompt check the Accessories submenu under Windows 2000. Click on MS-DOS Prompt and the initial MS-DOS screen (or window) will appear You can boot the system from an MS-DOS system diskette. If you shut down Windows, the third option on the shut down menu is Restart the computer in MS-DOS mode. Stay with the MS-DOS Prompt for now, however.

11. MS-DOS Seminar/Training • This tutorial gives you an opportunity to try basic MS-DOS commands. By following the procedures in this section, you will learn to: • View the contents of a directory • Change from one directory to another • Create and delete directories • Change from one drive to another • Copy files • Rename files • Delete files • Format a floppy disk

12. Common MS-DOS Commands

17. Below is a listing of each of the MS-DOS commands currently listed on Computer Hope and a brief explanation of what each of the commands do. Aansi.sysNSI.SYS Defines functions that change display graphics, control cursor movement, and reassign keys. append Causes MS-DOS to look in other directories when editing a file or running a command. arp Displays, adds, and removes arpinformation from network devices. assign Assign a drive letter to an alternate letter. assoc View the file associations. at Schedule a time to execute commands or programs.

18. atmadm Lists connections and addresses seen by Windows ATM call manager. attrib Display and change file attributes. batch Recovery console command that executes a series of commands in a file. bootcfg Recovery console command that allows a user to view, modify, and rebuild the boot.ini break Enable / disable CTRL + C feature. cacls View and modify file ACL’s. call Calls a batch file from another batch file. cd Changes directories. chcp Supplement the International keyboard and character set information. chdir Changes directories. chdsk Check the hard disk drive running FAT for errors.

19. chkntfs Check the hard disk drive running NTFS for errors. choice Specify a listing of multiple options within a batch file. cls Clears the screen. cmd Opens the command interpreter. color Easily change the foreground and background color of the MS-DOS window. command Opens the command interpreter. comp Compares files. compact Compresses and uncompress files. control Open Control Panel icons from the MS-DOS prompt. convert Convert FAT to NTFS.

20. copy Copy one or more files to an alternate location. ctty Change the computers input/output devices. date View or change the systems date. debug Debug utility to create assembly programs to modify hardware settings. defrag Re-arrange the hard disk drive to help with loading programs. del Deletes one or more files. delete Recovery console command that deletes a file. deltree Deletes one or more files and/or directories. dir List the contents of one or more directory. disable Recovery console command that disables Windows system services or drivers.

21. diskcomp Compare a disk with another disk. diskcopy Copy the contents of one disk and place them on another disk. doskey Command to view and execute commands that have been run in the past. dosshell A GUI to help with early MS-DOS users. drivparm Enables overwrite of original device drivers. echo Displays messages and enables and disables echo. edit View and edit files. edlin View and edit files. emm386 Load extended Memory Manager. ename Recovery console command to enable a disable service or driver.

22. fendlocal Stops the localization of the environment changes enabled by the set local command. erase Erase files from computer. exit Exit from the command interpreter. expand Expand a Microsoft Windows file back to it's original format. extract Extract files from the Microsoft Windows cabinets. fasthelp Displays a listing of MS-DOS commands and information about them. fc Compare files. fdisk Utility used to create partitions on the hard disk drive. find Search for text within a file. findstr Searches for a string of text within a file.

23. fixboot Writes a new boot sector. fixmbr Writes a new boot record to a disk drive. for Boolean used in batch files. format Command to erase and prepare a disk drive. ftp Command to connect and operate on a FTP erver. ftype Displays or modifies file types used in file extension associations. goto Moves a batch file to a specific label or location. graftabl Show extended characters in graphics mode. help Display a listing of commands and brief explanation. if Allows for batch files to perform conditional processing.

24. ifshlp.sys 32-bit file manager. ipconfig Network command to view network adapter settings and assigned values. keyb Change layout of keyboard. label Change the label of a disk drive. lh Load a device driver in to high memory. listsvc Recovery console command that displays the services and drivers. loadfix Load a program above the first 64k. loadhigh Load a device driver in to high memory. lock Lock the hard disk drive. logoff Logoff the currently profile using the computer.

25. logon Recovery console command to list installations and enable administrator login. map Displays the device name of a drive. md Command to create a new directory. mem Display memory on system. mkdir Command to create a new directory. mode Modify the port or display settings. more Display one page at a time. move Move one or more files from one directory to another directory. msav Early Microsoft Virus scanner. msd Diagnostics utility. msdex Utility used to load and provide access to the CD-ROM.

26. nbtstat Displays protocol statistics and current TCP/IP connections using NBT net Update, fix, or view the network or network settings netsh Configure dynamic and static network information from MS-DOS. netstat Display the TCP/IP network protocol statistics and information. nlsfunc Load country specific information. nslookup Look up an IP address of a domain or host on a network. path View and modify the computers path location. pathping View and locate locations of network latency. pause Command used in batch files to stop the processing of a command.

27. ping Test / send information to another network computer or network device. popd Changes to the directory or network path stored by the pushd command. power Conserve power with computer portables. print Prints data to a printer port. prompt View and change the MS-DOS prompt. pushd Stores a directory or network path in memory so it can be returned to at any time. qbasic Open the QBasic. rd Removes an empty directory. ren Renames a file or directory. rename Renames a file or directory. rmdir Removes an empty directory.

28. route View and configure windows network route tables. runas Enables a user to execute a program on another computer. scandisk Run the scandisk utility. scanreg Scan registry and recover registry from errors. set Change one variable or string to another. setlocal Enables local environments to be changed without affecting anything else. setver Change MS-DOS version to trick older MS-DOS programs. share Installs support for file sharing and locking capabilities. shift Changes the position of replaceable parameters in a batch program.

29. shutdown Shutdown the computer from the MS-DOS prompt. smartdrv Create a disk cache in conventional memory or extended memory. sort Sorts the input and displays the output to the screen. start Start a separate window in Windows from the MS-DOS prompt. subst Substitute a folder on your computer for another drive letter. switches Remove add functions from MS-DOS. sys Transfer system files to disk drive. telnet Telnet to another computer / device from the prompt. Time View or modify the system time. title Change the title of their MS-DOS window.

30. Tracert Visually view a network packets route across a network. tree View a visual tree of the hard disk drive. type Display the contents of a file. undelete Undelete a file that has been deleted. unformat Unformat a hard disk drive. unlock Unlock a disk drive. ver Display the version information. verify Enables or disables the feature to determine if files have been written properly. vol Displays the volume information about the designated drive. xcopy Copy multiple files, directories, and/or drives from one location to another.

31. Selecting the Default Drive The last line on the screen holds the MS-DOS prompt: C:\WINDOWS> The letter C is the current default drive (on most systems, C indicates the hard drive). To the right, the greater than (>) symbol indicates that MS-DOS is waiting for you to enter a command. WINDOWS is the name of the current directory.

32. Insert a blank diskette into a diskette drive. Then type the letter A followed by a colon; the prompt line should read C:\WINDOWS>A: Although the sample commands will be typed upper case, you can type MS-DOS commands in either upper case or lower case. A new prompt will appear A:\> Drive A is now the default. Make sure the prompt reads A:\> before you move on the next step.

33. Formatting Diskette The formatting process writes a pattern of sectors on the disk surface, records a copy of the boot routine on the first sector, initializes second information. The FORMAT command is used to format a disk. The simplest form consists of a single word: FORMAT. Be careful, however, because format is a destructive command. When you format a disk, you lose whatever data might be stored on it. Caution: If your default drive is a hard drive (for example, drive C), do not, under circumstances, format that disk. You could destroy your system. Before you move on to the next step in this tutorial, make sure your default drive is your diskette drive (usually, drive A). If not, type A: and press the enter key. Even with the default drive set correctly, it is a good idea to specify the target drive as part of your command. For example, type the command FORMAT A:

34. The File System The MS-DOS file system allows a users to identify, save, and retrieve files by name. Note that a program is a type of file. File Names A file name is composed of the name itself and an optional extension. The name consists of from 1 to 8 characters. A few file names are reserved by the system, and delimiters may not be used. Otherwise, just about any combination of characters you can type is legal. The file name is separated from its optional, 1 to 3 character extension by a period. Some extensions have a special meaning to the operating system. The extension is sometimes used to identify a version of a program or data file. For example: VITA.1, VITA.2 and so on. Directories Directory management is a key function of the MS-DOS file system. The first time a file is written to disk, its name, disk address, creation date, and other information are recorded in the directory. Later, when the file is retrieved, the operating system reads the directory and searches it by name. When a file is modified, the file system updates its directory entry. When the file is deleted, its directory entry is deleted.

35. Subdirectories When a disk is first formatted, a single root directory is created by the format routine. Using a single directory is fine for a few files, but as the number of files increases, distinguishing them becomes increasingly difficult. For example, imagine a work disk that holds several different types of files. To simplify keeping track of the files, MS-DOS allows the user to create special files called subdirectories. Path Names When subdirectories are used, you need more than a simple file name to find a file. For example, it is possible to have files named PAY stored on two different subdirectories. A reference to PAY would does be ambiguous –which PAY do you mean? To fully identify a file you need a complete path name. For example: \LETTERS\PAY and \WS\PAY are two different files.

36. Batch Files A Batch file is a file of precoded MS-DOS commands. You can assign any file name to a batch file, but the extension must be .BAT. If you type the batch file’s name and press enter. MS-DOS will execute the commands in sequence. For example, a file named AUTOEXEC.BAT is automatically executed each time the system is booted(if such a file exists). Program Files A program is a special type of file. By convention, executable programs are assigned the extension .COM or .EXE. To load and execute a program, simply type its file name (with or without its extension) as though it was a command. If no extension is given, MS-DOS will look for a command with the specified file name and a .COM extension, then search for a .EXE file, and finally for a .BAT file.

37. Pipes, Filters, and Redirection Many MS-DOS commands assume a standard input or output device; for example, the directory command sends its output to the screen. By using redirection parameters the user can change those defaults. For example, the command DIR>PRN sends the output directory listing to the printer. A filter is a special type of command. It accepts input from the standard input device, modifies (or filters) the data in some way, and sends the results to the standard output device. For example, the SORT filter accepts data from the keyboard, sorts the data into alphabetical or numerical sequence, and outputs the sorted data to the screen. You can add redirection parameters to override or change the standard input device, output device, or both. Try an example. Make sure your diskette is in the drive and type the command SORT <A:\LETTERS\JIM

38. Because of the redirection parameter (<), this SORT filter accepts its input from the file named JIM. The output, the lines of text that you typed when you created JIM sorted into alphabetical order, should appear on your screen. For future reference, to sort and store the output on a different file, code something like SORT<MYFILE>RESULT Note that both source and destination redirection parameters are included. The MORE command is another useful filter. It sends output to the terminal one screen at a time. MORE is often used with pipes. A pipe causes one command’s standard output to be used as the standard input to another command. Pipes are designed by a vertical line (|); you will find this character near the top right of most alphanumeric keyboards. For example, type C:

39. And press enter to make drive C your default drive and WINDOWS your current directory. Then type DIR Press enter, and watch the file names scroll by too quickly to read. Now type the command DIR | MORE The directory command’s standard output will be routed to the MORE filter rather than directly to the screen. The filter will display one screen and then wait until you press the enter key before it displays the next one. Try another experiment. Sort the WINDOWS directory and then display it one screen at a time. It’s easy. Just code DIR|SORT|MORE And press enter. Not that the file names are displayed one screen at a time in alphabetical order.

40. Returning to Windows That completes the chapter tutorial. To return to Windows, type the command EXIT And press the enter key. MS-DOS is a powerful operating system and you have barely scratched the surface of its command language. However, given a clear understanding of the commands in this brief tutorial, you should be able to read a reference manual and determine how to use additional commands on your own.

41. Evaluating an Operating System • If an operating system is to be a hardware/software interface, it makes sense to design an efficient interface. Thus, on most modern computers, the operating system serves as the primary resource manager, responsible for managing processor time, memory space, registers, input and output devices, secondary storage space, and data and program libraries. A well-designed operating system attempts to optimize the utilization of all the system resources. • Measures of Effectiveness • A number of criteria are used to measure a computer systems performance, including: • Throughput. Generally, total execution time (for all programs) divided by total elapsed time. • Turnaround. The elapsed time between job submission and job completion. • Response time. The elapsed time between a request for the computer’s attention and the computer’s response. • Availability. • Security. • Reliability. • Cause. • Ease of use.

42. MS-DOS Internals MS-DOS was once the world’s most commonly used microcomputer operating system. Although it has been largely supplanted by Microsoft Windows, it still runs under Windows. The Shell MS-DOS is command driven. Users request support by typing commands in response to a system prompt. When the return key is pressed, the shell, called COMMAND.COM, interprets the command and calls the appropriate lower level routine or program. COMMAND.COM consists of a program interpreter and a number of resident operating system routines that remain in memory at all times. Other routines are transient and are read into memory on demand. Generally, those routines needed to support an active program are resident.

43. Accessing Peripherals The task of accessing peripheral devices is divided between two operating system modules. IO.SYS is a hardware dependent module that is used physical data transfer commands. This module interacts with the basic input/output system (BIOS) usually implemented in read-only memory. Logical I/O is implemented by a hardware independent module called MSDOS.SYS. MSDOS.SYS accepts logical input/output from application programs or other operating system modules, translates them into physical I/O commands, and passes the physical commands to IO.SYS. Each physical device attached to the computer is described in a special file called a device driver. Character drivers control such devices as the keyboard, the screen and the printer.

44. Interrupt Processing The interrupt itself consists of an electronic pulse and the address of an interrupt vector. When an interrupt occurs, hardware immediately copies the contents of the IP register to the stack, and loads the specified interrupt vector into the IP register. Once, the interrupt is processed the contents of the stack are copied back into the IP register, and the original program resumes processing. Interrupts are much more common than you might imagine. For example, each time you press a key on the keyboard, an interrupt is generated. In response, the operating system copies a single character into memory and then waits for the next interrupt to herald the arrival of the next character. Hardware response to a software-generated interrupt exactly as if the source had been hardware, copying the IP register to the stack and loading the contents of the specified vector into IP register.

45. Booting MS-DOS Memory is volatile; it loses its contents when the computer loses power. Consequently, the operating system must be read into memory each time the computer is switched on. Under MS-DOS, the boot routine is stored on the first sector of each disk. Flipping the power switch (or simultaneously pressing CTRL, ALT, and DELETE) causes hardware to read into memory the first sector from the disk in the system drive. The COMMAND.COM modules that immediately follow MSDOS.SYS are resident. Other COMMAND.COM modules are stored at the high end of memory following the transient area.

46. Running MS-DOS Once loaded, MS-DOS controls literally everything that happens on the computer. First, COMMAND.COM gets control and, by calling IO.SYS, displays a system prompt on the screen. As the user types a command, each character generates an interrupt. Responding to the interrupt, the operating system reads the character, stores it in memory, and again using IO.SYS, display it. The basic work flow is simple. A prompt is displayed. The user types a command or program name. The appropriate operating system module or application program gets control. As the program runs, the operating system provides support by processing interrupts. Eventually, the module returns control to COMMAND.COM and the process is repeated, again and again, until the machine is shut down. MS-DOS is command driven.

47. The File System The MS-DOS file system allows users to identify, save, and retrieve files by name. Note that a program is a type of file. MSDOS.SYS converts logical I/O requests to physical form. One of its responsibilities is directory management. MSDOS.SYS also supports application programs. When a disk file is first opened, MSDOS.SYS asks IO.SYS to read the directory. It then extracts the location of an existing file or creates a directory entry for a one and, if necessary, asks IO.SYS. MSDOS.SYS responsibility is allocating space on disk. Quickly overview a disk format. Disk space allocated in clusters. Each cluster holds 1,024 bytes. The clusters are numbered sequentially with zero and the file allocation table contains an entry for each cluster on the disk. MS-DOS views the data’s word in a disk file as a continuous stream of bytes. Logical I/O operations request data by relative byte. MS-DOS.SYS calls IO.SYS to perform whatever physical input/output operations are necessary to access the requested string. Logically, data on disks are addressed just like data in memory.

48. Set the Date and Time Most computers on campus have an internal clock that will automatically set the date and time for you when you turn the computer on. However, if your computer does not have this feature or your computer has two floppy drives, you will need to do the following steps to set the date and time. Directions: 1. Type the date like this: 1-15-97 2. Press the return key (enter key). 3. Type the time like this: 8:46 4. Press return. 5. Notice that the C:\> prompt will appear. DOS marks the date and time on everything you do. It is important to periodically check the date and time if you have an internal clock to see if it is correct. If you have a two floppy system, it is important to enter the correct date and time when you turn the computer on.

49. Check the Date and Time DOS will let you check or change the date and time once it has been set. The procedure to do this is as follows: Directions: 1. Type: date and press return. 2. If the correct date is displayed, simply press return. If the date is incorrect, type the correct date and press return. 3. Type: time and press return. 4. If the correct time is displayed, simply press return. If the time is incorrect, type the correct time and press return. Directory Command The DIRECTORY command is like a table of contents in a book. This directory will list the following information: · Filenames · File extensions · Size of each file · Date and time the file was last updated. Directions: 1. At the C:\> type: dir and press return. 2. The list of files will scroll up and off the screen. NOTE: At the end of the listing, there is a line that shows the number of bytes free on the hard drive.

50. At first glance, subdirectories may seem to complicate rather than simplify the task of accessing files. In practice, however, people rarely use such lengthy path names. Instead, they select a working directory and allow the operating system to keep trackof the subdirectories needed to complete a path name. Create a File with DOS Directions: 1. Type: copy con Eimz.txt and press return. 2. Type this message in the following format: Eiman is beautiful joke. 3. Press the F6 function key (^Z) and press return. 4. DOS gives you a message that 1 File(s) has been copied. 5. Type: dir e* and press return. 6. Now you can see the list of files beginning with the letter E.