DOS

Dos

Disk Operating System

1. DOS (Disk Operating System:-

            DOS (Disk Operating System) was the first widely-installed operating system for personal computers. The first personal computer version of DOS, called PC-DOS, was developed for IBM by Bill Gates and his new Microsoft Corporation. He retained the rights to market a Microsoft version, called MS-DOS.

PC-DOS and MS-DOS are almost identical and most users have referred to either of them as just "DOS." DOS was (and still is) a non-graphical line-oriented command- or menu-driven operating system

2. The Command Prompt

When you first turn on your computer, you will see some cryptic information flash by. MS-DOS displays this information to let you know how it is configuring your computer. You can ignore it for now. When the information stops scrolling past, you'll see the following:

C:\>

This is called the command prompt or DOS prompt. The flashing underscore next to the command prompt is called the cursor. The cursor shows where the command you type will appear.

3. Files in MS DOS

In computers data is stored in files. When you run a program, MS-DOS processes the data stored in the file and passes it to the system.
In MS-DOS a file can be any size, however the file name is more restricted, it can only have a maximum length of 8 characters plus 3 for the extension.

Furthermore, the files can only contain the following characters:

·         letters A to Z

·         numbers 0 to 9

·         The following special characters: $~! # % & - { } ( ) @ ' _ ^

Thus filenames must not contain:

• spaces
• commas
• backslash
• dot (apart from the dot that separates the name and the extension)

Or can they contain any of the following lists of reserved names:

• CLOCK$
• CON
• AUX
• COM1
• COM2
• COM3
• COM4
• LPT1
• LPT2
• LPT3
• NUL
• PRN

4. Organizing files in directories or folders

Depending on its size a hard drive may contain several thousands of files. However, the more files there are, the more difficult it is to manage them, this is when we need to store them in directories In MS-DOS, directory names are also subject to the same name restrictions as files (8 characters for the name, and an extension with 3 characters)

5. Booting

When we start our Computer then there is an operation which is performed automatically by the Computer which is also called as Booting. In the Booting, System will check all the hardware’s and Software’s those are installed or Attached with the System and this will also load all the Files those are needed for running a system.

5.1 Types of Booting

            There are two Types of Booting

·        Warm Booting

·        Cold Booting

5.1.1) Warm Booting: when the System Starts from the Starting or from initial State Means when we Starts our System this is called as warm Booting. In the Warm Booting the System will be started from its beginning State means first of all, the user will press the Power Button, then this will read all the instructions from the ROM and the Operating System will be automatically gets loaded into the System.

 5.1.2) Cold Booting : The Cold Booting is that in which System Automatically Starts when we are Running the System, For Example due to Light Fluctuation the system will Automatically Restarts So that in this Chances Damaging of system are More. and the System will no be start from its initial State So May Some Files will b Damaged because they are not Properly Stored into the System.

6. Dos command divided into two parts:-

6.1 Internal command

6.2 External command

6.1 Internal command:-

These command included as part of the file COMMAND.COM and that resident in memory at all times while booting.

For example: DATE,TIME,CLS,DIR,VOL,VER,PROMPT,COPY        CON,COPY,DEL or ERASE,TYPE,REN,MD,CD,RD, etc.

DATE COMMAND:-

            Display or sets the date.

Syntax:          DATE [date]

Parameter:    mm-dd-yy

Example:       C :\> DATE <Press enter>>

Current date is sun 06-10-2012

Enter the new date (mm-dd-yy) : 05-12-2012

TIME COMMAND:-

Display or sets the system time.

Syntax:          TIME [time]

Parameter:    hh-mm-ss

Example:       C :\> TIME <Press enter>

Current time is 10:20:51:52

Enter the new time:

CLS COMMAND:-

            Clear the screen.

Syntax:          CLS

Example:       CLS <Press enter>

VOL COMMAND:-

Display the disk volume label and serial number, if they exits.

Syntax:          VOL [drive]

Example:       C :\> VOL <Press enter>

Volume in drive C is Bits

Volume serial number is 1c46–08f4

VER COMMAND:-

Display the windows version.

Syntax:          VER

Example:       C :\> VOL <Press enter>

Windows 98 (version 4.10.1998)

PROMPT COMMAND:-

Change the windows command prompt.

Syntax:          PROMPT [text]

Example:       C :\> PROMPT BITS$G  <Press enter>

BITS>PROMPT $P$G

Prompt can be made up of normal characters and the following special code:

$Q       = (equal sign)

$$        $ (dollar sign)

$T       Current time

$D       Current date

$P        Current drive and path

$V       Windows version number

$N       Current drive

$G       > (Greater than)

$L       < (Less than)

$B       | (pipe)

$H       Backspace (erase previous character)

Type PROMPT without parameter to reset the prompt to the default setting:

            C:\> Prompt $P$G

DIR COMMAND:-

Display a list of file and subdirectories in a directory.

Syntax:          DIR [drive:] [path] [filename] [/P][/W][/A][[:]                           [attributes]] [/O] [[:]sort order]] [/S] [/B] [/L] [/V]                           [/4] [Drive:] [Path] [File name]

Switches:

/P        pauses after each screen full of information.

/W       Uses wide list format.

/A        Display files with specified attributes.

            Attributes:

D- Directories          

            R -Read-only files              

H -Hidden files        

            A -files ready for archiving           

S -System files                     

/O        List by files in sorted order.

                                     N By name (alphabetic)     S By size (Smallest first)

E By extension (alphabetic)           D By date & time

            Example:       DIR/ON, DIR/OS, DIR/OE, DIR/OE, DIR/OD

Switches:

/S         Displays files in specified directories and subdirectories.

/B        User bare format (no heading information or summary).

/L        Uses lowercase.

/V        Verbose mode.

/4         Displays year with 4 digits (ignored if /V also given)

MDCOMMAND:-

Create a directory.

Syntax:          MKDIR [drive:] path

                        MD [drive:] path

Example:       C :/> MKDIR RAMAYAN

                        C :/> MD Computer

CDCOMMAND:-

Create a directory.

Syntax:          CHDIR [drive:] path

                        CHDIR [..]

                        CD [drive:] path

                        CD [..]

Example:       C :/> CD RAMAYAN <Press enter>

                        C :/> RAMAYAN> <Press enter>

                        C :/> CD RAMAYAN/SHYAM/HARI <Press enter>

            C :/> RAMAYAN/SHYAM/HARI> <Press enter>

                                                C:/>RAMAYAN/SHYAM/HARI>CD\ <Press enter>

RDCOMMAND:-

Removes (deletes) a directory.

Syntax:          RMDIR [drive:] path

                        RD [drive:] path

Example:       RD Computer <Press enter>

COPY CON COMMAND:-

Create a text file. F6 or CTRL+Z to save the contents of a file.

Syntax:          COPY CON [drive:] [path] file name

Example:       COPY CON poem.txt <Press enter>

India is our country. F6 or CTRL+Z <Press enter>

1 File(s) copied

TYPE COMMAND:-

Display the contents of text files.

Syntax:          TYPE [drive:] [path] file name

Example:       TYPE poem.txt <Press enter>

India is our country.

COPY COMMAND:-

Copies or one or more file to another location.

Syntax:          COPY [/A|/B] source [/A|/B] + [/A|/B] [+…]                               [destination] [/A|/B] [/V] [/Y] [/-Y]

Source            specified the file or files to be copied

/A                    Indicates an ASCII text files.

/B                    Indicates a binary file.

/V                    Verifies that new files are written currently.

/Y                    suppresses prompting to confirm you want to overwrite an existing destination file.

/-Y                  Cause prompting to confirm you want to overwrite an existing destination file.

Example:  C:\>COPY POEM.TXT FRUIT.TXT <Press enter>

RENAME COMMAND:-

Rename a file/directory or files/directories.

Syntax:          RENAME [drive:] [path] [Directory name1] [File                                 name1]  [Directory name2] [File name2]

REN [drive:] [path] [Directory name1] [File name1] [Directory name2] [File name2]

Example:       REN FRUIR.TXT POEM.TXT <Press enter>

DEL/ERASE COMMAND:-

Deletes one or more files.

Syntax:          DEL [drive:] [path] filename [/P]

                        ERASE [drive:] [path] filename [/P]

Example:       DEL POEM.TXT  <Press enter>

6.2 External command:-

            These command which are not part of the file COMMAND.COM and that need executable file usually stored in the c:\DOS in MS-DOS environment.

For example: TREE, DELTREE, FIND, SORT, MORE, LABEL, DOSKey, XCOPY, ATTRIB, EDIT, DISKCOPY, CHKDSK, SCANDISK, etc.

COLOR COMMAND:-

            Sets the default console fore background and background colors.

      Syntax:  Color [attribute]

            Attributes:

            Color attributes are specified by two color hex dixit – the first corresponds to the background; the second the background. Each digit can be any of the following value:

0	Black	8	Gray
1	Blue	9	Light Blue
2	Green	A	Light Green
3	Aqua	B	Light Aqua
4	Red	C	Light Red
5	Purple	D	Light Purple
6	Yellow	E	Yellow
7	White	F	Light White

      Example:  C:\>  Color 4

                        C:\>  Color 4F

FIND COMMAND:-

Searches for a text string in a file or files.

Syntax:          FIND [/V] [/C] [/N] [/I] “string” [[drive:] [path]                                                             filename […]]

/V                    Displays all lines NOT containing the specified string.

/C                    Displays only the count of line containing the string.

/N                    Displays line number with the displayed line.

/I                      Ignore the case of characters when searching for the string.

“string”          specified the text string to find.

 

Example:       C:\> FIND “APPLE” POEM.TXT

                        C:\> FIND/V “APPLE” POEM.TXT                  

                        C:\> FIND/C “APPLE” POEM.TXT                 

            C:\> FIND/N “APPLE” POEM.TXT                 

          

SORT COMMAND:-

Sorts input and writes results to the screen, a file, or another device.

Syntax:          SORT [/R] [drive:] [path] [file name]

/R                    Reverse the sort order, that is, sort Z to A, then 9 to 0.

Example:       C:\> SORT POEM.TXT

                        C:\> SORT/R POEM.TXT

MORE COMMAND:-

      Display output one screen at a time.

      Syntax:          MORE [drive:] [path] file name

      Example:       C:\> MORE POEM.TXT

ATTRIB COMMAND:-

      Display or change files attributes.

            Syntax:          ATTRIB [+R] [+A] [+S] [+H] [drive:] [path]

                                    ATTRIB [-R] [-A] [-S] [-H] [drive:] [path]

           

            +          Sets an attributes

            -           Clears an attributes

            R         Read-Only file attributes

            A         Archive file attributes

            S          System file attributes

            H         Hidden file attributes

            Example:      C:\> ATTRIB +R MANISH.TXT

                                    C:\> ATTRIB +H MANISH.TXT

                                    C:\> ATTRIB -R MANISH.TXT

                                    C:\> ATTRIB -H MANISH.TXT

DELTREE COMMAND:-

      Delete a directory and all the subdirectory and files in it. To delete one or more files and directory.

      Syntax:          DELTREE [/Y] [drive:] [path] directory name

      /Y        Suppress prompting to confirm you want to delete the                               subdirectory.

      Example:       C:\> DELTREE MEMORY

                              C:\> DELTREE/Y MEMORY

LABEL COMMAND:-

            Create, change or delete the volume label of a disk.

            Syntax:            LABEL [drive:] [label name]

            Example:         C:\> Label DOS

CHKDSK COMMAND:-

      Check a disk and displays status report.

      Syntax:          CHKDSK [drive:]

      Example:      C:\> CHKDSK

EDIT COMMAND:-

            MS-DOS Editor Version 2.0.026 copy right© Microsoft Corp 1995.

                        Syntax:          Edit [/B] [/R] [File name]

                        /B        Force monochrome mode. 

                        /R        Load files in read only mode.

                        Example:       C:\> Edit/B  DOS.TXT

C:\> Edit/R  DOS.TXT

C:\> Edit  DOS.TXT

7. Wild Card:-

            Wildcards are symbols that enable you to perform an MS-DOS operation on more than one file at a time. A file specification that contains wildcards can refer to more than one file because it gives MS-DOS a pattern to match.

            There are two wildcard characters:

ü  Question mark wild card (?)

ü  Asterisk Wild card (*)

8. Batch Command:

A batch file or batch job is a collection, or list, of commands that are processed in sequence often without requiring user input or intervention. With a computer running a Microsoft operating system such as Windows, a batch file is stored as a file with a .bat file extension.