Internal commands.29to30

1. http://improvec.blogspot.in/
1
Internal commands

2. http://improvec.blogspot.in/
2
Objective
On completion of this period, you would be able On completion of this period, you would be able
to knowto know
Conventions usedConventions used
Internal commands Internal commands

3. http://improvec.blogspot.in/
3
Recap
DOS commands are divided into
Internal Commands
External Commands

4. http://improvec.blogspot.in/
4
Prerequisite
What is meant by command
An instruction which is used to
communicate with a computer system

We call this instruction a command

5. http://improvec.blogspot.in/
5
Internal Commands
Internal commands are built–in commands
These commands are in COMMAND.COM
program
This program is loaded with the operating
system into the memory during booting

6. http://improvec.blogspot.in/
6
Internal Commands (contd)
Remains resident in the memory as long as
the computer is on
Hence they are always available to be
executed

7. http://improvec.blogspot.in/
7
Convention used in Command descriptions
are
[] (BRACKETS)
Items within brackets are optional
DRIVE
It refers to the drive name.
Example: C: A: B: etc

8. http://improvec.blogspot.in/
8
Convention used in Command descriptions
are (contd)
PATH
It refers to a directory name
Syntax :[\drive_directory] [\directory…]\ directory
PATHNAME
It mentions the files that are to be referred in
the path. It is used to locate a file
Syntax : [\drive_directory] [\directory…] \filename

9. http://improvec.blogspot.in/
9
Convention used in Command descriptions
are (contd)
SWITCHES
These switches control MS – DOS
commands. They should always begin with a
forward slash (/)
Example: /p /w etc

10. http://improvec.blogspot.in/
10
Convention used in Command descriptions
are (contd)
WILDCARDS
If we want to carry out a task for a group of
files whose names have something in common,
we can use wildcard characters to specify
groups of files

11. http://improvec.blogspot.in/
11
Wild characters
DOS recognizes two wildcard characters
Asterisk(*) – represents one or more characters
that a group of files has in common
Question mark(?) – represents a single
character that a group of files has in common

12. http://improvec.blogspot.in/
12
Examples of wildcards
*.txt : All files with .txt extension
Examples are letter.txt, july.txt, and message.txt
report.* - All files named report with any
extension.
Examples: report.txt, report.let and report.wri.

13. http://improvec.blogspot.in/
13
Examples of wildcards (contd)
M*.* : All files beginning with the letter M
regardless of extension.
Example are march.xls, memo.txt and
madhavi.lvu
 ???.* : all files having 3 or less characters with
or without any extensions.
Examples are sun.bmp, son.bm and ab.x

14. http://improvec.blogspot.in/
14
Internal Commands
 CLS- Clears the screen, takes the cursor to the
top left and the system Prompt appears at top
left
VER – It displays the MS-DOS version
DEL/ERASE [drive:] pathname – It deletes the
specified file or files. The wildcards (* and ?) can
be used with del command to delete more than
one file at a time

15. http://improvec.blogspot.in/
15
Internal Commands (contd)
 VOL [drive] – It displays the disk volume label
which is optionally declared at the time of
formatting
Example:
C:\>VOL A :
Result
Volume in drive A is DBASEIII
Volume Serial Number is 0909-07BE

16. http://improvec.blogspot.in/
16
Internal Commands (contd)
PROMPT [[text] [$character]…] – It changes the
MS-DOS command prompt. $ character prompts
are below

$t Current time $l <
$d Current date $q =
$n Drive letter $$ $
$p Directory $e Escape
$v Version number $g >
$h Backspace
$_ Return-Linefeed

17. http://improvec.blogspot.in/
17
Internal Commands (contd)
DATE [mm- dd- yy] - It displays or sets the date
Example:
C>DATE
Result:
Current date is FRI 21-04-07
Enter the new date (mm- dd- yy): 20-04-08
Now the current date will be SUN 20-04-08

18. http://improvec.blogspot.in/
18
Internal Commands (contd)
TIME [hours : minutes : seconds . Hundredths]
It allows to enter or change the time of the
system and see the current time
To type a new time, the valid values are hours is
0-23, minutes is 0-59, seconds is 0-59 and
hundredths of seconds 0-99

19. http://improvec.blogspot.in/
19
Internal Commands (contd)
Example1
C>TIME
Result
Current time is 1:28:40.51
Enter the new time : 11:07:51.21
Now the current time will be ’11:07:51.21

20. http://improvec.blogspot.in/
20
Internal Commands (contd)
Example2
C>TIME 12:07:59
C>TIME
Result
Current time is 12:07:59
Enter the new time :

21. http://improvec.blogspot.in/
21
Internal Commands (contd)
PATH [drive:] [path] [;[drive:] [path]…]
It sets a command search path for programs not
in the current directory
The above command is used to search more
than one path by specifying several paths
separated by semicolons

22. http://improvec.blogspot.in/
22
Internal Commands (contd)
DIR [drive:] [pathname] [/p] [/w] – To list the files
in a directory. Wildcards can also be used with
Dir command
Example1
C>DIR
Result
Volume in drive C is DOS400

23. http://improvec.blogspot.in/
23
Internal Commands (contd)
Directory of C:\vinay
. <dir> 1-11-90 1:05
..<dir> 1-09-90 13:05
BASIC EXE 67520 19-12-90 2:13
BUDGET BAS 814 1-01-91 1:45
FINAN90 BAS 3456 7-07-90 7:34
5 File (s)4329472 bytes free

24. http://improvec.blogspot.in/
24
Internal Commands (contd)
Example2
C>DIR/W
Result
Selects wide display and lists up to files lines
per line

25. http://improvec.blogspot.in/
25
Internal Commands (contd)
Example3
C>DIR/P
Result
Selects page mode and makes the directory
display to pause once the screen is filled
To resume scrolling the display any key can
be pressed

26. http://improvec.blogspot.in/
26
Internal Commands (contd)
TYPE [drive] filename – It displays the contents
of a text file on the screen
Example:
C>TYPE message.dat>PRN
Result
It sends the contents of file “message.dat” to
the printer

27. http://improvec.blogspot.in/
27
Internal Commands (contd)
COPY [drive:] [pathname] [drive:] [pathnamr2] –
It copies one or more files to another location
COPY pathname1 + pathname2 […]pathname..
It appends the files. Wildcards can also be used
with copy command

28. http://improvec.blogspot.in/
28
Internal Commands (contd)
Example1
C>copy bpay.rpt basicpay.rpt
Result
It copies a file named ‘bpay.rpt’ in the same
drive as
another name called ‘basicpay.rpt’

29. http://improvec.blogspot.in/
29
Internal Commands (contd)
Example2
C>copy BPAY.RPT A:PROLL.RPT
Result
It copies a file bpay.rpt from current drive C
to drive A named as proll.rpt

30. http://improvec.blogspot.in/
30
Internal Commands (contd)
Example3
C>COPY *.rpt + ref.txt summary.doc
Result
the above copy command combines all *.rpt
files and ref.txt files and stores in filename called
summary.doc

31. http://improvec.blogspot.in/
31
Internal Commands (contd)
MKDIR/MD [drive:] path – This command
creates required directory
Example
C>MKDIR letters
Result
It the above example, the command is used
to create a directory named letters

32. http://improvec.blogspot.in/
32
Internal Commands (contd)
CHDIR/CD [path] – It changes the current
directory for the specified directory
Example
C>CHDIR division
Result
The above command changes the working
directory to the directory called ‘division’

33. http://improvec.blogspot.in/
33
Internal Commands (contd)
RMDIR/RD [drive:] path – It removes a directory
from a directory structure
Example
C>RMDIR varsham
Result
The above command is used to remove the
directory named varsham
Before removing the directory entirely, the
directory should be empty.

34. http://improvec.blogspot.in/
34
Summary
In this class, we have learnt about
Internal commands – COPY, DEL,
DIR, TYPE, CD, MD, RD, MODE,
PATH, DATE, TIME, COPY CON etc.

35. http://improvec.blogspot.in/
35
Frequently Asked Questions
1.List any four DOS internal commands
2.What is DOS internal command?
3.Explain any four internal commands in DOS.

36. http://improvec.blogspot.in/
36
Quiz
Internal commands are _________
Answer: built in commands

37. http://improvec.blogspot.in/
37
Quiz
The instructions which are used to communicate
with the computer system
a. instructions
b. commands
Answer: b
37