Semester 2 Lab Manual 1

185253 COMPUTER PRACTICE LAB-II

TABLE OF CONTENTS

S.NO. NAME OF THE EXPERIMENT PAGE NO.

1 STUDY OF UNIX OPERATING SYSTEM

2 VI EDITOR

3 BASIC UNIXCOMMANDS

4 SHELL PROGRAM

ARITHMETIC OPERATION USING SHELL PROGRAM

5 GREATEST OF THREE NUMBERS

6 CHECKING WHETHER THE GIVEN NUMBER IS ARMSTRONG OR NOT

2

8 8.a. SWAPPING OF VALUES (Using 3rd Variable)

8.b. SWAPPING OF VALUES (Without using 3rd Variable)

9 NUMBER OF DIGITS IN AN INTEGER

10 ARITHMETIC OPERATIONS USING SHELL PROGRAMMING

(Using SWITCH - CASE)

11 FACTORIAL OF A NUMBER

12 CHECKING FOR PRIME NUMBER

S.NO. NAME OF THE EXPERIMENT PAGE NO.

13 SUMS OF DIGITS OF AN INTEGER

14

C PROGRAMMING UNDER UNIX ENVIRONMENT

3

MATRIX ADDITION

15 SORTING OF INTEGERS

16 EMPLOYEE DETAILS USING STRUCTURES

17 FILE MANIPULATION

18 GREAEST AND SMALLEST NUMBER IN AN ARRAY

19 TO CHECK WHETHER THE NUMBER IS A PALINDROME OR NOT

20 SYSTEM CALL FOR A READ – ONLY FILE

21 SYSTEM CALL FOR WRITE-ONLY FILE

4

22 IMPLEMENTATION OF COPY COMMAND

23 IMPLEMENTATION OF WC COMMAND

24 FORK SYSTEM CALL

25 EXECL SYSTEM CALL

5

STUDY OF UNIX OPERATING SYSTEM

Ex.No: 01

AIM:

To understand the basic definitions and features of Unix operating system.

Unix stands for unplaced information computing system.

6

VERSION OF UNIX:

T&T Bell laboratories: The operating system originated at the Bell laboratories.

VERSION:

The first commercially licensed version.

PWB/UNIX:

Programmers were bench this version includes specialized utilities to managing software development/

UNIX SYSTEM III:

The version includes as updated set of all the facilities of the passed two versions. It was the first Unix versions to be transported to a micro computer.

UNIX SYSTEM I:

It includes performance importance and enhanced process to process communication mostly one system III.

UNIVERSITY OF CALIFORNIA:

BSD - 4.1 Software development BSD - 4.2 BSD - 4.3

(i) MULTIUSER: Unix is a multi-user OS which permits more than one user to utilize the computer simultaneously any one of the connected terminals.

(ii) MULTI-TASKING:

7

The term task refers to a place initiated by the user to a process initiated by user Unix offer concept of classifying the task.

1. FOREGROUND TASK: It is the one where the user has to wait for the completion to present task before initiating the next task.

2. BACKGROUND TASK:

It is the one whose the user can continue interaction with the system while one or more of the presently issued task if is still executing.

3. PORTABLE: The application programs written for one system works on another system.

4. MODULATOR: It means the various part of the Unix system can be adder on the reproved without editing

performance of other component.

5. FILE STRUCTURE:

Unix has hierarchical file structure and imported free structure.

6. SECURITY:

Unix being a multi using operating system offers protection to user information from another. It maintains a list of users who are all allowed to access the system. The system also keep takes of that file and resources each user is authorized to renew user’s name to be added to the list before they have an access to the system.

TYPES OF USERS:

User is the owner of the file

8

The owner of the file is the one who has created the file or the one to the ownership has been transferred by the creates of the file.

GROUPS:

The members of the group have the same group I.D. but different user I.D.

OTHERS:

The other member who is neither the user nor the member of the group. Unix is a communication operating system. It is three level operating system.

Communication between terminals connected to the computer.

Communication between two compare of some place which cannot use the same either same hardware as software through local area network.

Communication between two computers at the remote location.

1. SHELL:

The shell is the Unix system command’s inter plater. The two important shells are

Bourse shell

C shell

2. KERNEL:

Kernel has the direct interaction with the hardware. It controls functions like file management-1, system, security of file, process management, scheduling management.

RESULT:

Thus the Unix environment has been studied.

VI EDITOR

9

Ex.No: 02

AIM:

To understand the basic functions and features of the VI editor

INSTRUCTIONS:

VI EDITOR- Visual editor

VI stands for Visual

The VI editor is the text editor. Originally developed for Unix programmers.

It is a model meaning. It is operating in the three different modes. The VI editor has been

Around for decade and is used daily by thousands of Linux and Unix users.

THREE ASPECTS OF VI:

VI is supplied with all Unix serpents VI can be used at other universities

or any business with UNIX system.

VI is a amount of memory allows efficient operation when the network is busy.

VI uses standard alphabetic keys for commands.

DIFFERENT MODES IN VI EDITOR

They are three different modes are available.

10

1. Command mode

2. Insert task

3. Last line or escape mode

1. COMMAND MODE

When the first start editing a file with the VI editor we will be VI connected

mode…. In this mode we can issue many VI commands, including insert, append delete, other search and navigation commands the let you move around your file.

2.INSERT MODE

Once we issue a VI editor insert append or open command we will be in VI insert mode. If we are working with a mode VI is typically configure to show the current mode of operation.

At this point, we can

A. Type text into our file

B. Uses of the arrow keys

we can easily move back to command mode by esc.

Cpy- Copying the current line.

Q - Heading

I - Insert the word.

11

3.LAST LINE MODE OR ESCAPE MODE:

The last VI mode is known as VI last line mode we can only get to last line mode from command mode we get into this mode by pressing the colon key.

After pressing the key, we will see a colon character appears at the beginning of the last line of our VI editor window and cursor will be moved to the position.

: w -to save our file but not quit VI.

: q -to quit if you haven’t left mode any edit.

:wq -to quit and save edits.

12

RESULT:

Thus the basic things about the editor and the 8 modes in VI editor had been studied.

BASIC UNIXCOMMANDS

Ex.No: 03

AIM:

To execute and implement the basic Shell UNIX commands.

1. DIRECTORY HANDLING COMMANDS AND THEIR OUTPUT:

1. [root@localhost root]# mkdir ram Creates a directory named “ram”2. [root@localhost root]# cd arun Enters into the directory “arun”

Example:

[ece@localhost ece]$ cd arun

[ece@localhost arun]$

3. [root@localhost arun]# cd .. Comes out of the directory “arun”[root@localhost root]

Example:

13

[ece@localhost ece]$ cd arun

[ece@localhost arun]$ cd ..

[ece@localhost ece]$

4. [root@localhost root]# pwd Shows the present working directory

Example:

[ece@localhost ece]$ pwd

/home/ece

5.[root@localhost root]# rmdirUsed to remove a directory

6.[root@localhost root]# ls Shows the list of files & directories

EXAMPLE:

[ece@localhost ece]$ ls

kanth

kar

kart

karth

karthick

karthik

karti

kat

katheeja

kathi

7.[root@localhost root]# ls -l List the permission of files / Directories

total 4

-rw-r--r-- 1 root root 1093 Mar 11 2006 anaconda-ks.cfg

-rw-r--r-- 1 root root 223 Mar 9 18:04 arith.sh

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-rw-r--r-- 1 root root 260 Mar 9 18:18 arm.sh

drwxr-xr-x 2 root root 4096 Mar 9 19:24 barnabas

2. FILE HANDLING COMMANDS.

1) [root@localhost root]# cat > msb Creates a New file “msb”I studying B.E ECE.

2) [root@localhost root]# cat msb Opens the created file “msb"I studying B.E ECE.

3) [root@localhost root]# cat >> msb Appends the details in the file “msb”I'm studying in Veltech Engineering college

4) [root@localhost root]# cat msbMy Name is Barnabas

I'm studying in Veltech Engineering college

5) [ece@localhost ece]$ cp ece1 ece2To create duplicate copies [ece@localhost ece]$ cat ece1

a

b

c

d

[ece@localhost ece]$ cat ece2

a

b

15

c

d

6) [ece@localhost ece]$ ln ece7 ece8To link two files


Iam studying in vel tech college

i am in ece dept

7) [root@localhost root]# rm msb Removes the file “msb”

rm: remove regular file `msb'? y

8)(i) [root@localhost root]# wc msb Shows the no. of lines, words & characters.

2 10 65 msb

(ii)[root@localhost root]# wc -l msb Shows the no. of lines alone.

2 msb

(iii)[root@localhost root]# wc -w msb Shows the no. of words alone.

10 msb

(iv)[root@localhost root]# wc -c msb Shows the no. of characters alone.

65 msb

9) [ece@localhost ece]$ mv ece9 ece0 ls to move ordinary and directory files


Iam studying in vel tech college

16

i am in ece dept


cat: ece9: No such file or directory

10) [ece@localhost ece]$ find ece8To find a file ece8

3. PATTERN SEARCHING COMMANDS.

1) [root@localhost root]# grep m msb Prints the sentence with the letter ‘m’ My Name is sudha

I'm studying in vel tech engineering college

2) [ece@localhost ece]$ egrep "are|our" yamuna1 to search for the multiple pattern we belong to our vel tech tech college

we are of ece students

3) [ece@localhost ece]$ fgrep "stands for" yamuna1 to extract only the fixed string without the use of any regular expression.

ece stands for electronic and conmmunication engineering

4. GENERAL PURPOSE COMMANDS.

I ) SIMPLE COMMANDS.

1. [root@localhost root]# cal Prints the calendar if the present month

March 2006

Su Mo Tu We Th Fr Sa

1 2 3 4

5 6 7 8 9 10 11

12 13 14 15 16 17 18

17

19 20 21 22 23 24 25

26 27 28 29 30 31

2. [root@localhost root]# date Prints the current time.

Thu Mar 9 19:26:27 IST 2006

3. [root@localhost root]# time –l Prints the System Run-time

real 0m0.005s

user 0m0.000s

sys 0m0.000s

4. [root@localhost root]# man cal Opens manual on “cal”

[ece@localhost ece]$ man cp

CP(1) FSF CP(1)

NAME

cp - copy files and directories

SYNOPSIS

cp [OPTION]... SOURCE DEST

cp [OPTION]... SOURCE... DIRECTORY

cp [OPTION]... --target-directory=DIRECTORY SOURCE...

DESCRIPTION

Copy SOURCE to DEST, or multiple SOURCE(s) to DIRECTORY.

18

Mandatory arguments to long options are mandatory for short options

too.

-a, --archive

same as -dpR

--backup[=CONTROL]

make a backup of each existing destination file

-b like --backup but does not accept an argument

:

5. [root@localhost root]# bc Open the Binary Calculator

bc 1.06

Copyright 1991-1994, 1997, 1998, 2000 Free Software Foundation, Inc.This is free software with ABSOLUTELY NO WARRANTY.

For details type `warranty'.

123 + 246

369

10 * 20

200

ii) STATUS INFORMATION COMMANDS

1. [ece@localhost ece]$ who –b Displays the date & time the system was brought up.

system boot Feb 23 23:02

19

2. [ece@localhost ece]$ who –s Displays the short form listing which consists of the username,terminal number and time fields.

ece pts/2 Feb 23 23:03 (10.0.0.5)

ece pts/1 Feb 23 23:03 (10.0.0.10)

ece pts/4 Feb 23 23:03 (10.0.0.36)

ece pts/6 Feb 23 23:04 (10.0.0.135)

ece pts/0 Feb 23 23:04 (10.0.0.119)

ece pts/3 Feb 23 23:04 (10.0.0.49)

ece pts/5 Feb 23 23:05 (10.0.0.137)

3. [ece@localhost ece]$ who –u Restricts listing to users currently logged in.ece pts/2 Feb 23 23:03 00:02 1723 (10.0.0.5)

ece pts/1 Feb 23 23:03 00:02 1674 (10.0.0.10)

ece pts/4 Feb 23 23:03 . 1993 (10.0.0.36)

ece pts/6 Feb 23 23:04 00:01 1998 (10.0.0.135)

ece pts/0 Feb 23 23:04 . 2101 (10.0.0.119)

ece pts/3 Feb 23 23:04 . 2149 (10.0.0.49)

ece pts/5 Feb 23 23:05 . 2223 (10.0.0.137)

4. [root@localhost root]# who am I Identifies the current working Systemroot pts/0 Mar 9 19:21 (:0.0)

5. [ece@localhost ece]$ ps –a Display the status of all the process associated with –u,g options

PID TTY TIME CMD

2311 pts/7 00:00:00 mail

20

2312 pts/3 00:00:00 ps

6. [ece@localhost ece]$ ps –g Display Inforamtion of all process of group loads specified in ggrplist

PID TTY STAT TIME COMMAND

2152 pts/3 S 0:00 -bash

2344 pts/3 R 0:00 ps –g

7. [ece@localhost ece]$ ps –l Lists the information using long format.F S UID PID PPID C PRI NI ADDR SZWCHAN TTY TIME CMD

4 S 502 2152 2149 0 75 0 - 1066 wait4 pts/3 00:00:00 bash

0 R 502 2348 2152 0 80 0 - 764 - pts/3 00:00:00 ps

8. [ece@localhost ece]$ tty It will retun the pathname with your terminal/dev/pts/3

9. [ece@localhost ece]$ id To Display the Numerical value that corresponda to your login name.uid=502(ece) gid=502(ece) groups=502(ece)

10. [ece@localhost ece]$ uname –a To display the relevant details about the Operating System on the standard output.Linux localhost.localdomain 2.4.20-6smp #1 SMP Thu Feb 27 09:59:40 EST 2003 i686 i686 i386 GNU/Linux

11. [ece@localhost ece]$ finger ece Gives you more Information about the User.Login: ece Name: (null)

Directory: /home/ece Shell: /bin/bash

On since Tue Feb 23 23:03 (IST) on pts/2 from 10.0.0.5

5 minutes 38 seconds idle


21



7 seconds idle









7 seconds idle



New mail received Tue Feb 23 23:08 2010 (IST)

Unread since Tue Feb 23 22:44 2010 (IST)

No Plan.

iii ) COMMUNICATION COMMANDS

1. [root@localhost root]# wall Hai To send message “hai” to all users there who are currently logged in.

Hai

2. [ece@localhost ece]$ mail ece To send the textual messages electrically transferred from one user to another.

Subject: Hai.

How are you.

22

All the best for your exams.

Have a nice day.

3. [ece@localhost ece]$ mail Read your mailMail version 8.1 6/6/93. Type ? for help.

"/var/spool/mail/ece": 1 messages 1 new

a) >N 1 [email protected] Tue Feb 23 23:06 18/720 "Hai."

&

Message 1:

From [email protected] Tue Feb 23 23:06:23 2010

Date: Tue, 23 Feb 2010 23:06:22 +0530

From: [email protected]

To: [email protected]

Subject: Hai.

How are you.Have you prepared for your exams.

ALL THE BEST FOR YOUR EXAMS.

Have a nice day.

b) & reply To send the reply to the specified user

To: [email protected] [email protected]

Subject: Re: Hai.

Thanks

Cc: & cse

Unknown command: "cse"

c)& exit Exit from the mail

d)&type Print the mail message

e)&delete Delete from the mail box

23

OTHER SHELL COMMANDS

I ) INPUT AND OUTPUT REDIRECTION COMMANDS

1. [root@localhost root]# > To redirect the output of a cammmand to a file.[ece@localhost ece]$ date>a1

[ece@localhost ece]$ cat a1

Tue Feb 23 22:59:03 IST ece@localhost ece]$

2. [ece@localhost ece]$ >> To append the output at the end of a file[ece@localhost ece]$ cat science

date

time

[ece@localhost ece]$ cat tech

one

two

[ece@localhost ece]$ cat science>>tech

[ece@localhost ece]$ cat tech

one

two

date

time


3. [ece@localhost ece]$< To redirect the output of a command to a file.[ece@localhost ece]$ cat<department

24

CSE

EEE


4. [ece@localhost ece]$ < >To redirect the output and input command to a file

[ece@localhost ece]$ cat<department>dnames

[ece@localhost ece]$ cat dnames

CSE

EEE


II ) SECURITY COMMANDS

1.[ece@localhost ram]$ ls –l To list files & Directories in long format

total 3

-rw-rw-r-- 1 ece ece 30 Feb 9 23:47 lop

-rwx------ 1 ece ece 30 Feb 9 23:43 pal

-rw-rw-r-- 1 ece ece 65 Feb 23 23:16 science

2. ece@localhost ram]$ chmod -ux science (-) denotes removing the permission

(u)denotes the user acess

(x) denotes executing permissions

[ece@localhost ram]$ ls -l

total 3


25


---------- 1 ece ece 65 Feb 23 23:16 science shows

Missing Permissions

3)[ece@localhost ram]$ chmod u+r,u+w science (+) denotes assigning

Permissions

(w) denotes writing permissions

(r)denotes reading permissions


total 3



-rw------- 1 ece ece 65 Feb 23 23:16 science the user now has reading writing permission

4) [ece@localhost ram]$ chmod u=x science (=)denotes assigning absolutely


total 3



---------- 1 ece ece 65 Feb 23 23:16 science

5) [ece@localhost ram]$ chmod g+r,g+w science (g)denotes group accessibility


total 3


26


----rw---- 1 ece ece 65 Feb 23 23:16 science the group

has now permission to access

6) [ece@localhost ram]$ chmod o+r,o+w science (o)denotes other user

accessibility


total 3



----rw-rw- 1 ece ece 65 Feb 23 23:16 science

7) [ece@localhost ram]$ chmod a+r,a+x science (a)denotes all user accessibility


total 3



-r-xrwxrwx 1 ece ece 65 Feb 23 23:16 science

III) WILD CARD PATTERNS

1. [ece@localhost ansatz]$ ls m* To representing any number of characters used in the prefix or suffix.

[ece@localhost raja]$ ls

kanna mvj mvs student vikram vikram]

[ece@localhost raja]$ ls m*

27

mvj:

mvs:

[ece@localhost raja]$



2. [ece@localhost raja]$ ls mv? To represent one character only either in the prefix or in the suffix of the file name



[ece@localhost raja]$ ls mv?

mvj:

mvs:


3. [ece@localhost raja]$ ls sh[1-4] To access a subset of related files


kanna mvj mvs sh1 sh2 sh3 sh4 sh5 student vikram vikram]

[ece@localhost raja]$ ls sh[1-4]

sh1:

sh2:

sh3:

sh4:

[ece@localhost raja]$

IV ) PIPES AND FILTERS COMMANDS

28

1. [ece@localhost ece]$ who |wc The output of “who”is taken as the input for the

“wc” and result is displayed.

9 54 426

2. [ece@localhost ece]$ who | tee names | wc –l The Use of tee command is to

store the intermediate results in a file.

16

[ece@localhost ece]$ cat names

ece pts/4 Feb 23 23:56 (10.0.0.135)

ece pts/17 Feb 24 00:05 (10.0.0.221)

ece pts/10 Feb 24 00:09 (10.0.0.15)

ece pts/13 Feb 24 00:13 (10.0.0.180)

ece pts/1 Feb 24 00:14 (10.0.0.49)

ece pts/24 Feb 24 00:14 (10.0.0.6)

ece pts/3 Feb 24 00:17 (10.0.0.36)

ece pts/30 Feb 24 00:19 (10.0.0.137)

ece pts/7 Feb 24 00:19 (10.0.0.34)

ece pts/28 Feb 24 00:22 (10.0.0.5)

ece pts/20 Feb 24 00:23 (10.0.0.120)

ece pts/21 Feb 24 00:24 (10.0.0.3)

ece pts/31 Feb 24 00:25 (10.0.0.119)

ece pts/34 Feb 24 00:25 (10.0.0.14)

ece pts/32 Feb 24 00:27 (10.0.0.4)

29

3. [ece@localhost ece]$ head -5 names To Display the First Five lines from a

File.

jack

arun

prashant

deepak

naga


4. [ece@localhost ece]$ tail -5 names To Display the Last Five lines from a

File.

ajith

superman

spiderman

goten

vegetables

5. (i)[root@localhost root]# sort msb1 Sorts in ascending order

Aravind

Balaji

Dinesh

Ganesh

Kamalesh

(ii) [root@localhost root]# sort -r msb1 Sorts in descending order

Kamalesh

30

Ganesh

Dinesh

Balaji

Aravind

6.[root@localhost root]# pr To display the Page number,File Creation date and

along with the name of the file.

[ece@localhost ece]$ pr g1

2010-02-25 02:38 g1 Page 1

echo ENTER THE NAME

read n

echo-n THE ENTERED NAME IS $n

7.[root@localhost root]# cut To cut the selected fields.

[ece@localhost ece]$ cat college

diva vh2346

jan vh2345

kavi vh2387

naru vh2876

subi vh2498

[ece@localhost ece]$ cut -c2 college

i

a

a

31

a

u


8.[root@localhost root]# paste To paste the contenet from one to another file.

[ece@localhost ece]$ cat college1

dhoni vh2376

raina vh2398

raj vh2270

subi vh2498

jan vh2345


divi vh2334

raina vh2398

raj vh2270

[ece@localhost ece]$ paste -d% college1 college2

dhoni vh2378

divi vh2334

raina vh2397

raina vh2398

raj vh2270

raj vh2270

subi vh2498%

jan vh2345

32

9.[root@localhost root]# join To extract the common lines from two sorted Files.


dhoni vh2376

raina vh2398

raj vh2270

subi vh2498

jan vh2345


divi vh2334

raina vh2398

raj vh2270

[ece@localhost ece]$ join –v1 college1 college2

dhoni vh2376

subi vh2498

jan vh2345


10.[root@localhost root]# uniq To Displays the adjacent duplicate lines in a existing file

[ece@localhost ece]$ cat tech3

nithu vh2272

uma vh2297

nithu vh2272[ece@localhost ece]$

[ece@localhost ece]$ uniq -c2 tech3

3 nithu vh2272


33

11.[root@localhost root]# nl Used to add Line Numbers to a File.

[cse@localhost cse]$ nl dept

1 cse

2 ece

3 eee

4 it

5 mech

[cse@localhost cse]$ nl -v4 deptstarts the numbering of each page

by 4

4 cse

5 ece

6 eee

7 it

8 mech

[cse@localhost cse]$ nl –i3 deptincrements number of lines by 3.

1 cse

4 ece

7 eee

10 it

13 mech

12.[root@localhost root]# tr It is used to translate characters taken from the standard input.

[cse@localhost cse]$ cat dept

cse

ece

34

eee

it

mech

[cse@localhost cse]$ cat dept|tr "[a-z]" "[A-Z]"

CSE

ECE

EEE

IT

MECH

13.[root@localhost root]# pg It displays the output of a command on the screen

page by page.

14.[root@localhost root]# more To Displays the output page by page

[ece@localhost ece]$ ls | more

0

00

000123

003

0045

007

1

10

100

10001

101

35

12

122

123

1234

1234567890

124

132

133

143

159

18

--More— Press Enter to see the next page.

15.[root@localhost root]# cmp Compare any two files, including binary files. It

takes two filenames as arguments.

[ece@localhost ece]$ cat > college

diva vh2346

jan vh2345

kavi vh2387

naru vh2876

subi vh2498

[ece@localhost ece]$ cat > college1

DHONI VH2876

RAINA VH2398

KAIF VH2657

36

HARI VH2765

SRI VH4567

[ece@localhost ece]$ cmp college college1

college college1 differ: byte 1, line 1

[ece@localhost ece]$ cat college[ece@localhost ece]$ cmp -b college college1

college college1 differ: byte 1, line 1 is 144 d 104 D

16.[root@localhost root]# diff Files are compared on line by line basis.

[ece@localhost ece]$ cat college

diva vh2346

jan vh2345

kavi vh2387

naru vh2876

subi vh2498


dhoni vh2387

raina vh2389

subi vh2498

sachin vh2564

diva vh2346

[ece@localhost ece]$ diff -e college college1

1,5c

dhoni vh2387

raina vh2389

subi vh2498

37

sachin vh2564

diva vh2346

[ece@localhost ece]$ diff -b college college1

1,4c1,2

< diva vh2346

< jan vh2345

< kavi vh2387

< naru vh2876

---

> dhoni vh2387

> raina vh2389

5a4,5

> sachin vh2564

> diva vh2346

17.[root@localhost root]# comm Compare and displays lines common as well as

unique to two files.

[ece@localhost ece]$ comm -1 college college1

dhoni vh2387

raina vh2389

subi vh2498

sachin vh2564

diva vh2346


dhoni vh2387

38

raina vh2389

subi vh2498

sachin vh2564

diva vh2346


diva vh2346

jan vh2345

kavi vh2387

naru vh2876

subi vh2498

RESULT:

Thus the Basic Shell Commands were executed.

ARITHMETIC OPERATION USING SHELL PROGRAM

Ex.No: 04

AIM:

To write a shell Program to do the Arithmetic Operations like Addition, Subtraction, Multiplication, Division.

39

ALGORITHM:

Step 1: Start

Step 2: Read the values of ‘a’ and ‘b’

Step 3: Write the expression to calculate sum, difference, Product, Quotient and Remainder.

Step 4: Print the Results

Step 5: Stop.

SHELL PROGRAM:

echo "Enter Two Numbers"

read a b

c=èxpr $a + $b`

d=èxpr $a - $b`

e=èxpr $a \* $b`

f=èxpr $a / $b`

g=èxpr $a % $b`

echo "Sum = $c"

echo "Difference = $d"

echo "Product = $e"

echo "Quotient = $f"

echo "Remainder = $g"

SAMPLE OUTPUT:

40

Enter Two Numbers

12 10

Sum = 22

Difference = 2

Product = 120

Quotient = 1

Remainder = 2

RESULT:

Thus the shell Program to do arithmetic operation was executed without any errors.

GREATEST OF THREE NUMBERS

Ex. No.: 05

AIM:

To write a shell program to find the greatest of three Numbers.

ALGORITHM:

Step 1: Start

Step 2: Read the value of ‘a’, ‘b’ and ‘c’

Step 3: Check if ‘a’ is greater than ‘b’ and ‘a’ is greater than ‘c’

Step 4: Then print “A is Greater”

Step 5: If Step 3 is not satisfied check if ‘b’ is greater than ‘c’

41

Step 6: Then print “B is Greater”

Step 7: Else Print “C is greater”

Step 8: Stop.

SHELL PROGRAM:

echo "Enter Three Numbers"

read a b c

if [ $a -gt $b -a $a -gt $c ]

then

echo "$a is Greater"

elif [ $b -gt $c ]

then

echo "$b is Greater"

else

echo "$c is Greater"

fi

SAMPLE OUTPUT:

Enter Three Numbers

12 14 16

16 is Greater

42

RESULT:

Thus the program to find the greatest of three Numbers was executed and the output was verfied.

CHECKING WHETHER THE GIVEN NUMBER IS ARMSTRONG OR NOT

Ex. No.: 06

AIM:

To check whether the given Number is Armstrong Number or not using Shell Programming.

ALGORITHM:

Step 1: Start

Step 2: Read the value of ‘num’

Step 3: Store the value of ‘num’ in ‘x’ and initialize the value of sum = 0.

Step 4: When the value of ‘num’ is greater then 0, solve the following expressions

Step 5: y = num/10; z=y*y*y; sum=num+z; num=num/10

Step 6: Close the While Loop

43

Step 7: Check if ‘x’ is equal to ‘sum’

Step 8: Print the Result

Step 9: Stop.

SHELL PROGRAM:

44

echo "Enter a Number"

read num

x=$num

sum=0

while [ $num -gt 0 ]

do

y=èxpr $num % 10`

z=èxpr $y \* $y \* $y`

sum=èxpr $sum + $z`

num=èxpr $num / 10`

done

if [ $x -eq $sum ]

then

echo "$x is an armstrong Number"

else

echo "$x is not an armstrong Number

Enter a Number

153 is an armstrong Number

[root@localhost root]# sh arm.sh

Enter a Number

123

123 is not an armstrong Number

45

RESULT:

Thus the Shell Program to check whether the given Number is Armstrong or not was executed and the output was verified.

FIBONACCI SERIES

Ex No.: 07

AIM:

To write a Shell Program to print the Fibonacci series.

ALGORITHM:

Step 1: Start

Step 2: Read the Value of ‘n’

Step 3: Initialize i=2; a=0; b=1.

46

Step 4: Print the Value of ‘a’ and ‘b’

Step 5: When ‘i’ is lesser than ‘n’, solve the expression c=a+b

Step 6: Print c

Step 7: Swap the Values of ‘b’ to ‘a’ and ‘c’ to ‘b’

Step 8: Solve the expression “i=i+1”

Step 9: Stop.

47

SHELL PROGRAM:

echo "Enter the Limit"

read n

i=2

echo "Fibonacci Series"

echo "----------------"

a=0

b=1

echo $a

echo $b

while [ $i -lt $n ]

do.

c=èxpr $a + $b`

echo $c

a=$b

b=$c

48

i=èxpr $i + 1`

done

SAMPLE OUTPUT:

Enter the Limit

8

Fibonacci Series

----------------

0

1

1

2

3

5

8

13

49

RESULT:

Thus the Shell Program to print the Fibonacci Series was executed and the output was verified.

SWAPPING OF VALUES

(Using 3 rd Variable)

Ex. No.: 08(a)

AIM:

To write a Shell Program to swap two values using 3rd variable.

ALGORITHM:

Step 1: Read the Values of ‘a’ and ‘b’

Step 2: Swap the values of ‘a’ to the third variable ‘temp’

Step 3: Swap the value of ‘b’ to ‘a’ and ‘b’ to ‘temp’

Step 4: Print the swapped values of ‘a’ and ‘b’

Step 5: Stop.

SHELL PROGRAM:

50


read a b

temp=$a

a=$b

b=$temp

echo $a $b

SAMPLE OUTPUT:

Enter Two Numbers

12 10

10 12

RESULT:

Thus the program to swap two values using 3rd variable was executed and the output was verified.

SWAPPING OF VALUES

51

(Without using 3 rd Variable)

Ex. No.: 08(b)

AIM:

To write a Shell Program to swap two values without using 3rd Variable.

ALGORITHM:

Step 1: Start

Step 2: Read the values of ‘a’ and ‘b’

Step 3: Solve the expression, a=a + b; b=a – b; a=a – b

Step 4: Print the swapped values of ‘a’ and ‘b’

Step 5: Stop

SHELL PROGRAM:


read a b

a=èxpr $a + $b`

52

b=èxpr $a - $b`

a=èxpr $a - $b`

echo $a $b

SAMPLE OUTPUT:

Enter Two Numbers

12 10

10 12

53

RESULT:

Thus the Shell Program to swap two values without using third variable was executed and the output was verified.

NUMBER OF DIGITS IN AN INTEGER

Ex. No.: 09

AIM:

To count the number of digits in an integer, using Shell Programming.

ALGORITHM:

Step 1: Start

Step 2: Read the value of ‘a’

Step 3: Initialize the value of c as 0

Step 4: When the value of ‘a’ is not equal to 0, solve n=a %10.

54

Step 5: If the value of ‘n’ is not equal to 0, solve c=c + 1(increment)

Step 6: End if condition

Step 7: Solve the expression “a=a / 10”

Step 8: Repeat steps 4 to 7 until ‘a’ is equal to 0

Step 9: Print the value of c as the number of digits in an integer.

Step 10: Stop.

SHELL PROGRAM:


read a

c=0

while [ $a -ne 0 ]

do

n=èxpr $a % 10`

c=èxpr $c + 1`

a=èxpr $a / 10`

done

echo "The Number of Digits in the Integer is $c"

SAMPLE OUTPUT:

Enter a Number

123456789

The Number of Digits in the Integer is 9

RESULT:

55

Thus the Shell Program to calculate the number of digits of an integer was executed and the output was verified.

ARITHMETIC OPERATIONS USING SHELL PROGRAMMING

(Using SWITCH - CASE)

Ex. No. 10

AIM:

To write a Shell Program to perform Arithmetic Operations using Switch – Case

ALGORITHM:

Step 1: Start

Step 2: Read the two Numbers.

Step 3: Get the operation choice from the User

Step 4: Give the expressions for each case and solve them.


Step 6: Stop

56

SHELL PROGRAM:


57

read a b

echo "What do you want to do? (1 to 5)"

echo "1) Sum"

echo "2) Difference"

echo "3) Product"

echo "4) Quotient"

echo "5) Remainder"

echo "Enter your Choice"

read n

case "$n" in

1) echo "The Sum of $a and $b is èxpr $a + $b`";;

2) echo "The Difference between $a and $b is èxpr $a - $b`";;

3) echo "The Product of the $a and $b is èxpr $a \* $b`";;

4) echo "The Quotient of $a by $b is èxpr $a / $b`";;

5) echo "The Remainder of $a by $b is èxpr $a % $b`";;

esac

SAMPLE OUTPUT:

[root@localhost Shell]# sh arith_switch.sh

Enter Two Numbers

12 10

What do you want to do? (1 to 5)

1) Sum

2) Difference

58

3) Product

4) Quotient

5) Remainder

Enter your Choice

4

The Quotient of 12 by 10 is 1

RESULT:

Thus the Shell program to perform arithmetic operations using Switch Case was executed and the output was verified.

FACTORIAL OF A NUMBER

Ex. No. 11

AIM:

To write a Shell Program to find the factorial of a Number.

ALGORITHM:

59

Step 1: Start

Step 2: Read the Number as ‘n’

Step 3: Assign the value of ‘p’ as 0 and solve the expression i = n-1

Step 4: While the value of ‘i’ is greater than or equal to 1 do the following steps.

Step 5: Solve the expression n=n*1 and i=i-1 (Decrementing Operation)

Step 6: Then print the value of ‘n’ as the factorial of the given number.

Step 7: Stop.

SHELL PROGRAM:


read n

i=èxpr $n - 1`

p=1

while [ $i -ge 1 ]

do

n=èxpr $n \* $i`

i=èxpr $i - 1`

done

echo "The Factorial of the given Number is $n"

SAMPLE OUTPUT:

60

[root@localhost Shell]# sh fact.sh

Enter a Number

5

The Factorial of the given Number is 120

RESULT:

Thus the Shell Program to find the factorial of the Number was executed and the output was verified.

CHECKING FOR PRIME NUMBER

Ex. No.: 12

AIM:

To write a Shell Program to check if the Number is a Prime Number or a Composite Number.

ALGORITHM:

Step 1: Start

Step 2: Read the Number as ‘n’

Step 3: Initialize the value of ‘t’ to 0 and solve the expression i=n-1

61

Step 4: While ‘i’ is greater than or equal to 2, perform the following steps.

Step 5: Solve p=n%i

Step 6: Check the condition (p=0) and then solve t=t+1

Step 7: End the If Condition

Step 8: Solve the expression i=i-1

Step 9: If ‘t’ is greater than 0, print “The Number is not a Prime Number”

Step 10: If the condition is not satisfied, print “The Number is a Prime Number”

62

SHELL PROGRAM:


read n

i=èxpr $n - 1`

t=0

while [ $i -ge 2 ]

do

p=èxpr $n % $i`

if [ $p -eq 0 ]

then

t=èxpr $t + 1`

fi

i=èxpr $i - 1`

done

if [ $t -gt 0 ]

then

echo "The Number $n is not a Prime Number"

63

else

echo "The Number $n is a Prime Number"

fi

SAMPLE OUTPUT:

[root@localhost Shell]# sh prime.sh

Enter a Number

2

The Number 2 is a Prime Number

[root@localhost Shell]# sh prime.sh

Enter a Number

4

The Number 4 is not a Prime Number

RESULT:

64

Thus the Shell Program to check if the given number is prime or not, was executed and the output was verified.

SUMS OF DIGITS OF AN INTEGER

Ex. No. 13

AIM:

To write a Shell Program to calculate the sum of digits of an Integer.

ALGORITHM:

Step 1: Start

Step 2: Read the Integer as ‘num’

Step 3: Initialize the value of sum=0.

Step 4: While the value of ‘num’ is greater than 0, solve the following expressions.

Step 5: Find the remainder of ‘num’ by 10 and store in ‘y’

Step 6: Add ‘sum’ with ‘y’ and store it in ‘sum’

Step 7: Divide ‘num’ by 10 and store the value in ‘num’

Step 7: Close the while loop


Step 9: Stop

SHELL PROGRAM:


65

read num

sum=0

while [ $num -gt 0 ]

do

y=èxpr $num % 10`

sum=èxpr $sum + $y`

num=èxpr $num / 10`

done

echo "The Sum of the Digits of the Integer is $sum"

SAMPLE OUTPUT:

[root@localhost Shell]# sh digits_sum.sh

Enter a Number

123456

The Sum of the Digits of the Integer is 21

RESULT:

Thus the Shell program to calculate the sum of the digits of the integer was executed and the output was verified.

C PROGRAMMING UNDER UNIX ENVIRONMENT

MATRIX ADDITION

66

Ex. No. 14

AIM:

To write a C Program to add two matrices under UNIX Environment

ALGORITHM:

Step 1: Start

Step 2: Declare a[10][10], b[10][10], add[10][10], i, j, m, n.

Step 3: Get the number of rows and columns as m and n respectively

Step 4: Scan the values of the matrices according to the values of m and n.

Step 5: Add the two matrices directly and store the values in ‘add[10][10]’

Step 6: Using ‘for loop’ print the values of add[10][10]

Step 7: End the loop

Step 8: Stop.

67

C PROGRAM:

#include<stdio.h>

main()

{

int add[10][10],a[10][10],b[10][10],i,j,m,n;

printf("\nEnter the Number of Rows and Columns:\n\n ");

scanf("%d%d",&m,&n);

68

printf("Enter the 1st Matrix: \n\n");

for(i=0;i<m;i++)

for(j=0;j<n;j++)

scanf("%d",&a[i][j]);

printf("Enter the 2nd Matrix: \n\n");

for(i=0;i<m;i++)

for(j=0;j<n;j++)

scanf("%d",&b[i][j]);

for(i=0;i<m;i++)

{

for(j=0;j<n;j++)

add[i][j]=a[i][j]+b[i][j];

}

printf("The Addition of the two matrices is: \n");

for(i=0;i<n;i++)

{

printf("\n\n");

for(j=0;j<n;j++)

{

printf("%d\t",add[i][j]);

}

}

}

69

SAMPLE OUTPUT:

[root@localhost C_Program]# cc matadd.c

[root@localhost C_Program]# ./a.out

Enter the Number of Rows and Columns:

2

2

Enter the 1st Matrix:

70

1

2

3

4

Enter the 2nd Matrix:

1

2

3

4

The Addition of the two matrices is:

2 4

6 8

71

RESULT:

Thus the C Program to add two matrices under UNIX Environment was executed and the output was verified.

SORTING OF INTEGERS

Ex. No. 15

AIM:

To write a C Program to sort an array of integers under UNIX environment

ALGORITHM:

Step 1: Start

Step 2: Get the number of array integers as ‘n’

Step 3: Using ‘for loop’, get the ‘n’ number of integers as a[]

Step 4: Again using ‘for loop’ check if the second number is greater than the first

72

Step 5: If the above step is true, swap the value of second to first

Step 6: Repeat Steps 4 and 5 for all the integers scanned using ‘for loop’

Step 7: Again using ‘for loop’ print the sorted list of values.

Step 8: Stop

73

C PROGRAM:

#include<stdio.h>

main()

{

int x[50],n,i,j,temp;

printf("How many Numbers ?\n");

scanf("%d",&n);

printf("\nEnter the List of %d numbers:\n",n);

for(i=0;i<n;i++)

scanf("%d",&x[i]);

for(i=0;i<n-1;i++)

for(j=i+1;j<n;j++)

if(x[i]>x[j])

{

temp=x[i];

x[i]=x[j];

x[j]=temp;

}

printf("\nThe Sorted list of Numbers is \n");

for(i=0;i<n;i++)

74

printf("%d\t",x[i]);

}

SAMPLE OUTPUT:

[root@localhost C_Program]# cc sort.c


How many Numbers ?

5

Enter the List of 5 numbers:

4

8

3

6

2

The Sorted list of Numbers is

2 3 4 6 8

RESULT:

Thus the C Program to sort the given array of integers under UNIX environment was executed and the output was verified.

EMPLOYEE DETAILS USING STRUCTURES

75

Ex. No.: 16

AIM:

To write a C Program to get and print the employee details using Structures under UNIX Platform.

ALGORITHM:

Step 1: Start

Step 2: Initialize the structure with employee no., name and salary.

Step 3: Inside the main function, get the number of employees

Step 4: Using for loop, scan the employee details

Step 5: Again using for loop, print the employee details

Step 6: Stop

76

C PROGRAM:

#include<stdio.h>

struct emp

{

char name[25];

77

int salary;

int empno;

}a[20];

Ma in()

{

int n,i;

printf("\n Enter the Number of Employees: ");

scanf("%d",&n);

for(i=0;i<n;i++)

{

printf("\n\nEnter the %d Employee details",i+1);

printf("\n\n1.Employee No.: ");

scanf("%d",&a[i].empno);

printf("\n2.Name: ");

scanf("%s",&a[i].name);

printf("\n3.Salary: ");

scanf("%d",&a[i].salary);

}

for(i=0;i<n;i++)

{

printf("\n\nEmployee %d",i+1);

printf("\n1.Employee No.: %d",a[i].empno);

printf("\n2.Employee Name: %s",a[i].name);

printf("\n3.Salary: %d",a[i].salary);

}

78

}

SAMPLE OUTPUT:

[root@localhost C_Program]# cc employ.c


Enter the Number of Employees: 2

Enter the 1 Employee details

1.Employee No.: 1234

79

2.Name: Ramesh

3.Salary: 12500

Enter the 2 Employee details


2.Name: Ganesh

3.Salary: 12500

Employee 1


2.Employee Name: Ramesh

3.Salary: 12500

Employee 2


2.Employee Name: Ganesh

3.Salary: 12500

80

RESULT:

Thus the C Program to get and print the employee details using Structures was executed and the output was verified.

FILE MANIPULATION

Ex. No.: 17

AIM:

To write a C Program to perform following file manipulation:

1. Read a file2. Copy a file3. Change the case of the entire file4. Count the number of words, spaces and lines in a file.

C PROGRAM:

#include<stdio.h>

#include<string.h>

main()

81

{

char ch,ct;

int choice,tr,letters=0,words=0,spaces=0,lines=0;

FILE *fp1,*fp2;

do

{

fp1=fopen("data1.txt","r");

printf("\nEnter u'r Choice\n");

printf("\n1.Read the file\n2.Copy the file\n3.Change\n4.Count\n5.Exit\n");

scanf("%d",&choice);

switch(choice)

{

case 1:

while(!feof(fp1))

{

ch=getc(fp1);

printf("%c",ch);

}

break;

case 2:

fp2=fopen("data2.txt","w");

fseek(fp1,0L,SEEK_SET);

while(!feof(fp1))

{

ct=fgetc(fp1);

82

tr=fputc(ct,fp2);

}

fclose(fp1);

fclose(fp2);


printf("The Content of the copied file is ");

while(!feof(fp2))

{

ch=fgetc(fp2);

printf("%c",ch);

}

fclose(fp2);

break;

case 3:


while(!feof(fp2))

{

ch=getc(fp2);

if((ch<91)&&(ch>=65))

{

ch=ch+32;

printf("%c",ch);

}

else if((ch>=97)&&(ch<=122))

{

83

ch=ch-32;

printf("%c",ch);

}

else

{

printf("%c",ch);

}

}

break;

case 4:


while(!feof(fp2))

{

ch=fgetc(fp2);

if(ch==' ')

{

spaces++;

}

else if (ch=='\n')

{

lines++;

}

else

{

letters++;

84

}

}

printf("\nTotal lines: %d",lines);

printf("\nTotal words: %d",spaces+lines);

printf("\nTotal spaces: %d",spaces);

printf("\nTotal letters: %d",spaces+lines+words);

fclose(fp2);

break;

}

}

while(choice!=5);

}

SAMPLE OUTPUT:

Enter u'r Choice

1.Read the file

2.Copy the file

3.Change

4.Count

5.Exit

1

Wisdom better than the Rubies.

85

?

Enter u'r Choice

1.Read the file

2.Copy the file

3.Change

4.Count

5.Exit

2

The Content of the copied file is Wisdom better than the Rubies.

??

Enter u'r Choice

1.Read the file

2.Copy the file

3.Change

4.Count

5.Exit

3

wISDOM BETTER THAN THE rUBIES.

??

Enter u'r Choice

1.Read the file

2.Copy the file

86

3.Change

4.Count

5.Exit

4

Total lines: 1

Total words: 5

Total spaces: 4

Total letters: 5

87

RESULT:

Thus the FILE MANIPULATION operation was performed and the output was verified.

GREAEST AND SMALLEST NUMBER IN AN ARRAY

Ex.No.: 18

AIM:

To write a C Program to find the greatest and smallest number in an array of integers.

ALGORITHM:

88

Step 1: Start

Step 2: Get the maximum limit for the array as ‘n’

Step 3: Using ‘for’ loop, get the array of integers to the value of ‘n’

Step 4: Again using ‘for’ loop, sole the following conditions.

Step 5: If the first digit is greater than the second, perform the following swap conditions.

Step 6: Swap the value of a[0] to ‘temp’, a[j] to a[i] and a[i] to ‘temp’.

Step 7: Print the result

Step 8: Stop

89

PROGRAM:

#include<stdio.h>

main()

{

int a[100],i,j,n,temp;

printf("\nEnter the maximum limit: ");

scanf("%d",&n);

printf("\nEnter %d numbers: \n",n);

for(i=0;i<n;i++)

scanf("%d",&a[i]);

for(i=0;i<n;i++)

{

for(j=i+1;j<n;j++)

90

{

if(a[i]>a[j])

{

temp=a[i];

a[i]=a[j];

a[j]=temp;

}

}

}

printf("\nThe smallest number is %d",a[0]);

printf("\nThe biggest number is %d",a[n-1]);

}

SAMPLE OUTPUT:

[root@localhost C_Program]# cc maxmin.c


Enter the maximum limit: 5

Enter 5 numbers:

9

6

2

10

15

The smallest number is 2

91

The biggest number is 15

RESULT:

Thus the C Program to find the greatest and smallest number in an array was executed and the output was verified.

TO CHECK WHETHER THE NUMBER IS A PALINDROME OR NOT

Ex. No.: 19

AIM:

To write a C Program to check if the given number is a palindrome or not

ALGORITHM:

Step 1: Start

Step 2: Get the number as ‘n’

Step 3: Swap the value of ‘n’ to ‘c’.

Step 4: While the value of ‘n’ is greater than or equal to 1, solve the following expressions.

Step 5: Store the remainder of ‘n’ by 10 as ‘a’; Solve b=(b*10)+a; and n=n/10

92

Step 6: If the value of ‘c’ is equal to ‘b’, print “The number is a palindrome”.

Step 7: If the above condition is not satisfied, print “The number is not a palindrome”.

Step 8: Stop.

93

PROGRAM:

#include<stdio.h>

main()

{

int a,c,n,b=0;

printf("\nEnter a number: ");

scanf("%d",&n);

c=n;

while(n>=1)

{

a=n%10;

b=(b*10)+a;

n=n/10;

}

if(c==b)

printf("\nThe number is a palindrome\n");

else

printf("\nThe number is not a palindrome\n");

}

94

SAMPLE OUTPUT:

[root@localhost C_Program]# cc palin.c


Enter a number: 12321

The number is a palindrome


Enter a number: 123

The number is not a palindrome

RESULT:

Thus the C Program to check whether the number is a palindrome or not was executed and the output was verified.

SYSTEM CALL FOR A READ – ONLY FILE

Ex. No.:20

95

AIM:

To write C Program to perform system call to open for a read-only file.

ALGORITHM:

Step 1: Start

Step 2: Initialize the integer variables- i and fd. Also initialize the string variable, buf[100].

Step 3: Open the already created file ‘aa’ as a read only and store its contents in fd.

Step 4: Read fd, buf, 100

Step 5: Using for loop, print the character array, buf[i]

Step 6: The data already stored in ‘aa’ along with the garbage value will be printed as output.

Step 7: Stop

Note:

A file ‘aa’ with data must be created before the program is compiled and is run, to avoid segmentation error.

Header Files:

fcntl.h File control Options

96

unistd.h Standard symbolic constants and types.

PROGRAM:

#include<stdio.h>

#include<fcntl.h>

#include<unistd.h>

main()

{

int i,fd;

char buf[100];

fd=open("aa",O_RDONLY);

97

read(fd,buf,100);

for(i=0;i<100;i++)

{

printf("%c",buf[i]);

}

}

SAMPLE OUTPUT:

[root@localhost C_Program]# cc syscall-r.c


My name is Barnabas

t��<@PB@,X@&8Z@0�@�@c@TB

B

98

RESULT:

Thus the C Program for system call to open a read-only file was executed and the output was verified.

SYSTEM CALL FOR WRITE-ONLY FILE

Ex. No.: 21

AIM:

To write a C Program to perform system call to open a write-only file.

ALGORITHM:

Step 1: Start

Step 2: Initialize the integer variables – ‘i’ and ‘fd’ with a character variable ‘buf[100]’.

Step 3: Get the data form the user and store it as ‘buf’.

99

Step 4: Open the file ‘aa’ as write-only and store it in fd.

Step 5: Write the data given by the user to the file and ‘fd’

Step 6: Stop

Note:

After the program is run, open the file ‘aa’ to find the garbage values stored in it.

A file ‘aa’ with data must be created before the program is compiled and is run, to avoid segmentation error.

Header Files:

fcntl.h File control Options

unistd.h Standard symbolic constants and types.

100

PROGRAM:

#include<stdio.h>

#include<fcntl.h>

#include<unistd.h>

main()

{

int i,fd;

char buf[100];

printf("Give data: ");

scanf("%s",buf);

fd=open("aa",O_WRONLY);

write(fd,buf,sizeof(buf));

}

SAMPLE OUTPUT:

[root@localhost C_Program]# cc syscall-w.c


Give data: I study in VEC

[root@localhost C_Program]# cat aa

101

IBe�B�B

Bt��<@PB@,X@-8Z@0�@�@c@TBB

RESULT:

Thus the C Program to perform system call to opena write-only file was executed and the output was verified.

IMPLEMENTATION OF COPY COMMAND

102

Ex. No.: 22

AIM:

To write a C Program to implement copy command in UNIX.

ALGORITHM:

Step 1: Start

Step 2: Open the file to be copied, and store it in fp1

Step 3: Open a new file, where the contents are to be copied and store it in fp2.

Step 4: Copy all the characters one by one until the End of File.

Step 5: Close all the files.

Step 6: Stop.

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C PROGRAM:

#include<stdio.h>

main(int a, char *av[2])

{

char ch;

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FILE *fp1,*fp2;

fp1=fopen(av[1],"r");

fp2=fopen(av[2],"w");

while((ch=getc(fp1))!=EOF)

{

putc(ch,fp2);

}

fclose(fp1);

fclose(fp2);

}

SMAPLE OUTPUT:

[root@localhost C_Program]# cc copy.c

[root@localhost C_Program]# cat>a

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[root@localhost C_Program]# ./a.out a b

[root@localhost C_Program]# cat b

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105

RESULT:

Thus the C Program to implement copy command in UNIX was executed and the output was verified.

IMPLEMENTATION OF WC COMMAND

Ex. No.: 23

AIM:

To write a C Program to implement wc command in UNIX.

ALGORITHM:

Step 1: Start

106

Step 2: Initialize the variables c=0; w=0; l=0.

Step 3: Using If – Else condition count the no. of characters, letters and words.

Step 4: Using string compare function, print the result with respect to the command given.

Step 5: Stop.

107

C PROGRAM:

#include<stdio.h>

main(int a,char *av[3])

{

FILE *f;

char ch;

int w=0,l=0,c=0;

if(a==2)

f=fopen(av[1],"r");

else

f=fopen(av[2],"r");

while(!feof(f))

{

ch=getc(f);

c=c++;

if(ch==' '||ch=='\n')

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w=w+1;

if(ch=='\n')

l=l+1;

}

fclose(f);

if(strcmp(av[1],"-c")==0)

printf("\nThe no. of characters are %d\n",c-1);

else if(strcmp(av[1],"-w")==0)

printf("\nThe no. of words are %d\n",w);

else if(strcmp(av[1],"-l")==0)

printf("\nThe number of lines are %d\n",l);

else if(av[2]=='\0')

printf("\n%d\t%d\t%d\n",c-1,w,l);

}

SAMPLE OUTPUT:

[root@localhost C_Program]# cc wc.c

[root@localhost C_Program]# ./a.out msb

77 10 7

[root@localhost C_Program]# ./a.out -l msb

The number of lines are 7

[root@localhost C_Program]# ./a.out -w msb

The no. of words are 10

[root@localhost C_Program]# ./a.out -c msb

The no. of characters are 77

109

RESULT:

Thus the C Program to implement wc commad in UNIX was executed and the output was verified.

FORK SYSTEM CALL

Ex. No.: 24

AIM:

To write a C Program for FORK SYSTEM CALL

ALGORITHM:

Step 1: Start

Step 2: Open the inbuilt function fork() inside the header file, unistd.h and store it in f

Step 3: When f is equal to 0, print the Child process ID, Parent ID and the process ID, using inbuilt ID functions.

Step 4: Stop.

110

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C PROGRAM:

#include<stdio.h>

#include<unistd.h>

main()

{

int f;

f=fork();

if(f==0)

{

printf("\nChild Process ID: %d\n",getpid());

printf("\nParent ID: %d\n",getppid());

}

else

{

printf("\nProcess ID: %d\n",getpid());

printf("\nParent ID: %d\n",getppid());

}

}

SAMPLE OUTPUT:

[root@localhost C_Program]# cc fork.c


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Child Process ID: 3844

Parent ID: 3843

Process ID: 3843

Parent ID: 3673

RESULT:

Thus the C Program for Fork System Call in UNIX was executed and the output was verified.

EXECL SYSTEM CALL

Ex. No.: 25

Date: 3rd May, 2006

113

AIM:

To write a C Program for EXECL System Call in UNIX

ALGORITHM:

Step 1: Start

Step 2: Give the command for Execl, to print the Date and Time.

Step 3: Stop

C PROGRAM:

#include<stdio.h>

#include<unistd.h>

main()

{

execl("/bin/date","date",0);

}

SAMPLE OUTPUT:

[root@localhost C_Program]# cc execl.c


Tue May 2 18:01:37 IST 2006

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[root@localhost C_Program]#

RESULT:

Thus the C Program for EXECL System Call in UNIX was executed and the output was verified.

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Documents

Semester 2 Lab Manual 1