FAMILIARIZATION OF OPEARTING SYSTEM (MS-DOS)

FAMILIARIZATION OF OPEARTING SYSTEM (MS-DOS)

OBJECTIVES:

            MS-DOS is a simple operating system that is text-oriented and command-based. The MS-DOS command-line interface was designed solely for keyboard input, as opposed to a mouse-based graphical user interface (GUI), like the Macintosh, where the user chooses commands by pointing and clicking on onscreen objects. It is relatively small in size, and is universally compatible with all PCs (since it was designed to run on the very first one). It starts up fairly quickly on most hardware, uses little memory, and allows direct access to hardware, unlike most protected mode operating systems today.

THEORY:

            MS-Dos is Microsoft Disk operating System. MS-DOS is an operating system designed for the IBM PC by Microsoft in 1981. It was a command-line interface, meaning the user had to type in commands to use it, unlike Windows which is a Graphical User Interface. MS DOS was released on IBM PCs when they came out in the 1980s and continued in popular use until the mid 1990s, by which time the first of the Windows operating systems, Windows 95, began to take over. 

MS DOS commands were either stored as individual programs, known as external commands, or in a file called Command.com, which stored more commonly used commands. These were called internal commands. Included in these would have been commands like COPY, DEL, DIR, CD and RD. COPY enabled the copying of files. DEL deleted files. DIR gave a listing of files in a directory (now called a folder). CD changed from one directory to another. RD removed a directory.

 During its life, several competing products were released for the x86 platform, and MS-DOS itself would go through eight versions, until development ceased in 2000. Ultimately it was the key product in Microsoft's growth from a programming languages company to a diverse software development firm, providing the company with essential revenue and marketing resources. It was also the underlying basic operating system on which early versions of Windows ran as a GUI.

SYNTAX 0R SOURCE CODE:

Some source codes of MS-DOS are as follows:-

c:\>cls

c:\>dir

c:\>md

c:\>date

c:\>time

c:\>ver

c:\>vol

c:\>copycon <file name>

c:\>copy <old file name> <new file name>

c:\>ren< old file name> <new file name>

c:\>document and setting>users>cd

c:\>rd dl

c:\>edit<file name>

c:\>type< file name>

OUTPUT:

Output of above sources codes:-

cls

Clears the screen.

cls

Equivalent to the Unix

cd 

displays the current working directory on the current drive.

cd directory

copy

Copies files from one location to another. The destination defaults to the current directory. If multiple source files are indicated, the destination must be a directory, or an error will result.

Syntax:

copy [source\filename] [destination\folder]

dir

Lists the contents of a directory.

The dir command typed by itself, displays the disk's volume label and serial number; one directory or filename per line, including the filename extension, the file size in bytes, and the date and time the file was last modified; and the total number of files listed, their cumulative size, and the free space (in bytes) remaining on the disk. The command is one of the few commands that exist from the first versions of DOS.

dir [drive:][path][filename] [parameters]

md                                                                         

Makes a new directory. The parent of the directory specified will be created if it does not already exist.

md directory

rd

Remove a directory (delete a directory), by default the directories must be empty of files for the command to succeed. The deltree command in some versions of MS-DOS, and all versions of Windows 9x removes, non-empty directories.

rmdir /s

The [/s] parameter enables rmdir to function in the same way as deltree, deleting all sub folders and Files, and by default requiring confirmation.

rmdir /s /q

The [/q] parameter, if present, tells the rmdir command to carry out the deletion without first prompting for confirmation. This is the same as running deltree [/y].

time and date

Display and set the time and date

time

date

When these commands are called from the command line or a batch file, they will display the time or date and wait for the user to type a new time or date and press RETURN. The commands time /t and date /t will display output without waiting for input.

ver

An internal DOS command, which reports the DOS version presently running, and since MS-DOS 5, whether DOS is loaded high. The corresponding command to report the Windows version is winver.

edit

Full-screen text editor, included with MS-DOS 5 and 6, OS/2 and Windows NT to 4.0

Windows 95 and later, and W2k and later use Edit v2.0

PC DOS 6 and later use the DOS E Editor.

DR-DOS used editor up to version 7.

ren

Renames a file. Unlike the move command, this command cannot be used to rename subdirectories, or rename files across drives.

ren filename newname

We can rename files in another directory by using the PATH parameter.

DISCUSSION:

DOS is very lightweight and it allows direct access to most hardware. But it does not have the overhead of a multitasking operating system. It is 16-bit and limited to 640k of RAM. It runs in real mode, so a buggy or evil program can cause corruption. It’s a Single User OS and Single Tasking OS.It does not support Graphics and Networking.We can only make 2GB of maximum partition as it supports only fat 16.

People are using it for various purposes. People, who enjoy either playing DOS games or DOS programming, and don't want to do so in another way, such as via an emulator.People who either rely on or don't want to stop using programs they regularly use in MS-DOS. Even today, many of the best computer diagnostics programs run via DOS. This is because MS-DOS provides raw access to the hardware, unlike in a protected mode operating system.

CONCLUSION:

DOS is very stable and runs on almost any machine, even Macintosh. In addition it is not so sensitive to current fluctuations and current outages. DOS provides a reasonable step from a non-digital world to a digital world. And the slight loss of efficiency in not having multi-tasking and slower printing is offset by the lower wage structure.  There were versions of DOS developed and support equipment including printers and fonts for all different alphabets. So still it is in use.