Experiment-1
Write a Shell script to print the command line arguments in reverse order.
#!/bin/sh
if [ $# -eq 00 ]
then
echo "no arguments given"
exit
fi
echo "Total number of arguments: $#"
echo "The arguments are: $*"
echo "The arguments in reverse order:"
rev=" "
for i in $*
do
rev=$i" "$rev
done
echo $rev
Output 1
$ ./print-arguments-in-reverse.sh
no arguments given
Output 2
$ ./print-arguments-in-reverse.sh 9 abc hello
Total number of arguments: 3
The arguments are: 9 abc hello
The arguments in reverse order:
hello abc 9
Experiment 2
Write a Shell script to check whether the given number is palindrome or not.
echo enter n
read n
num=0
on=$n
while [ $n -gt 0 ]
do
num=$(expr $num \* 10)
k=$(expr $n % 10)
num=$(expr $num + $k)
n=$(expr $n / 10)
done
if [ $num -eq $on ]
then
echo palindrome
else
echo not palindrome
fi
OUTPUT:
$ enter n
$ 121
$ palindrome
EXPERIMENT 3
Write a Shell script to sort the given array elements in ascending order using bubble sort.
# Sorting the array in Bash
# using Bubble sort
# Static input of Array
arr=(10 8 20 100 12)
echo "Array in original order"
echo ${arr[*]}
# Performing Bubble sort
for ((i = 0; i<5; i++))
do
for((j = 0; j<5-i-1; j++))
do
if [ ${arr[j]} -gt ${arr[$((j+1))]} ]
then
# swap
temp=${arr[j]}
arr[$j]=${arr[$((j+1))]}
arr[$((j+1))]=$temp
fi
done
done
echo "Array in sorted order :"
echo ${arr[*]}
Output :
Array in sorted order :
8 10 12 20 100
EXPERIMENT 4
• Write a Shell script to perform sequential search on a given array elements.
echo Enter the number of elements:
read n
echo Enter the array elements:
for (( i=1; i<=n; i++ ))
do
read a[$i]
done
echo Enter the element to be searched:
read item
j=1
while [ $j -lt $n -a $item -ne ${a[$j]} ]
do
j=`expr $j + 1`
done
if [ $item -eq ${a[$j]} ]
then
echo $item is present at location $j
else
echo "$item is not present in the array."
fi
Experiment 5-
Write a Shell script to perform binary search on a given array elements.
echo “Enter the limit:”
read n
echo “Enter the numbers”
for(( i=0 ;i<n; i++ ))
do
read m
a[i]=$m
done
for(( i=1; i<n; i++ ))
do
for(( j=0; j<n-i; j++))
do
if [ ${a[$j]} -gt ${a[$j+1]} ]
then
t=${a[$j]}
a[$j]=${a[$j+1]}
a[$j+1]=$t
fi
done
done
echo “Sorted array is”
for(( i=0; i<n; i++ ))
do
echo “${a[$i]}”
done
echo “Enter the element to be searched :”
read s
l=0
c=0
u=$(($n-1))
while [ $l -le $u ]
do
mid=$(((( $l+$u ))/2 ))
if [ $s -eq ${a[$mid]} ]
then
c=1
break
elif [ $s -lt ${a[$mid]} ]
then
u=$(($mid-1))
else
l=$(($mid+1))
fi
done
if [ $c -eq 1 ]
then
echo “Element found at position $(($mid+1))”
else
echo “Element not found”
fi
OUTPUT
Enter the limit: 5
Enter the numbers
42637
Sorted array is
23467
Enter the number to be searched :7
Element found in position 5
EXPERIMENT 6-
Write a Shell script to accept any two file names and check their file permissions
if [ $# -ne 2 ]
then
echo "no arguments pls enter 2 arguments"
elif [ ! -e $1 -o ! -e $2 ]
then
echo "File does not exist"
else
per1=`ls -l $1 | cut -c 2-10`
per2=`ls -l $2 | cut -c 2-10`
if [ $per1 = $per2 ]
then
echo "Permissions are Identical:permission is $per1"
else
echo "Permissions are not Identical"
echo "permission of $1 is $per1"
echo "permission of $2 is $per2"
fi
fi
OUTPUT:
sh 8a.sh
no arguments please enter 2 arguments
sh 8a.sh 1.c 2.c
Permissions are Identical: permission is rw-r--r—
chmod 777 1.c
sh 8a.sh 1.c 2.c
Permissions are not Identical
permission of 1.c is rwxrwxrwx
permission of 2.c is rw-r--r—
Experiment-7
• Write a Shell script to read a path name, create each element in that path e.g: a/b/c
i.e., ‘a’ is directory in the current working directory, under ‘a’ create ‘b’, under ‘b’ create ‘c’
→
#!/usr/bin/python
import sys
import os.path
if len(sys.argv)>1:
for i in range(1,len(sys.argv)):
print os.path.abspath( sys.argv[i] )
sys.exit(0)
else:
print >> sys.stderr, "Usage: ",sys.argv[0]," PATH."
sys.exit(1)
EXPERIMENT 8-
Write a Shell script to illustrate the case-statement.
$ cat signal.sh
#!/bin/bash
if [ $# -lt 2 ]
then
echo "Usage : $0 Signalnumber PID"
exit
fi
case "$1" in
1) echo "Sending SIGHUP signal"
kill -SIGHUP $2
;;
2) echo "Sending SIGINT signal"
kill -SIGINT $2
;;
3) echo "Sending SIGQUIT signal"
kill -SIGQUIT $2
;;
9) echo "Sending SIGKILL signal"
kill -SIGKILL $2
;;
*) echo "Signal number $1 is not processed"
;;
Esac
$ sleep 1000
$ ps -a | grep sleep
23277 pts/2 00:00:00 sleep
$ ./signal.sh 9 23277
Sending SIGKILL signal
$ sleep 1000
Killed
Q 9:-Write a Shell script to accept the file name as arguments and create another shell
script, which recreates these files with its original contents.
#!/bin/bash
echo “Enter the file path”
read FILE
if [ -f “$FILE” ]
then
echo “$FILE is a reguler file”
elif [ -d “$FILE” ]
then
echo “$FILE is a directory”
else
echo “$FILE is another type of file”
fi
ls -l $FILE
output
[svimukthi@sanka Shell_Scripting]$ ./exe6.sh
Enter the file path
/home/svimukthi/sanka
/home/svimukthi/sanka is a directory
total 4
drwxr-xr-x. 2 svimukthi svimukthi 30 Nov 13 20:18 hs
-rw-rw-r — . 1 svimukthi svimukthi 12 Nov 12 12:09 sanka.txt
d — x — — — . 2 svimukthi svimukthi 20 Dec 13 18:53 test
EXPERIMENT10
Write a Shell script to demonstrate Terminal locking.
echo "\nEnter the password:\c"
stty -echo
read pass1
echo "\nRetypr password"
read pass2
if [ $pass1 = $pass2 ] ; then
tput clear
echo "\nThe terminal is locked\n"
echo "\nEnter password to unlock:"
read pass3
while [ $pass1 != $pass3 ]
do
echo "\nEnter password to unlock"
read pass3
done
else
echo "\nTerminal could not be locked"
fi
stty echo
EXPERIMENT 11
Write a Shell script to accept the valid login name, if the login name is
valid then print its home directory else an appropriate message.
#!/bin/bash
# getlogin-name.sh : A shell script to display login name
## Let us change variable values ##
USER="foo"
LOGNAME="bar"
## Greet user ##
## Display imposter name i.e. you can not trust $USER and $LOGNAME ##
echo "Hi,$USER! You are Imposter, for sure. Sorry, I can not trust you."
echo "Hello, $LOGNAME! You are Imposter, for sure. I cannot trust you. Go away! "
## Display real login name ##
echo "Hello, $(logname)! Let us be friends."
SAMPLE OUTPUTS-
Hi,foo! You are Imposter, for sure. Sorry, I can not trust you.
Hello, bar! You are Imposter, for sure. I cannot trust you. Go away!
Hello, vivek! Let us be friends.
EXPERIMENT 12
Write a Shell script to read a file name and change the existing file
permissions.
#!/bin/bash
file=~/scripts/text.txt
if [ -e $file ]
then echo "The file exists"
elif [ ! -e $file ]
then echo "The file does NOT exist"
fi
sleep 1s
if [ ! -w $file ]
then { sudo chmod u+w $file; } && { echo "The file is now writable"; }
elif [ -w $file ]
then echo "The file is already writable"
fi
EXPERIMENT 13
Write a Shell script to print current month calendar and to replace the current day number by ‘*’ or
‘**’ respectively.
set `date`
y=$3
if [ $y -le 9 ]
then
cal |sed "s/$3/*/"
else
cal |sed "s/$3/**/"
fi
EXPERIMENT 14
Write a Shell Script to display a menu consisting of options to display disk space, the
current users logged in, total memory usage, etc. ( using functions.)
#!/bin/bash
# function to show memory usage
memoryUsage(){
echo "Memory Usage:"
free
read -p "Press any key to Continue...."
}
# function to show disk usage
diskUsage(){
echo "Disk Usage:"
df
read -p "Press any key to Continue...."
}
# function to show menu
show_menu()
{
clear
echo "++++++++++++ MENU +++++++++++++"
echo "1. Show Memory Usage."
echo "2. Show DIsk Usage."
echo "3. Exit"
echo "+++++++++++++++++++++++++++++++"
}
# function to take input
take_input()
{
#take the input and store it in choice variable
local choice
read -p "Select the option from above menu: " choice
#using swich case statement check the choice and call function.
case $choice in
1) memoryUsage ;;
2) diskUsage ;;
3) exit 0;;
*) echo "Enter Valid Option!!"
read -p "Press any key to Continue...."
esac
}
# for loop to call the show_menu and take_input function.
while true
do
show_menu
take_input
done
EXPERIMENT 15
Write a C-program to fork a child process and execute the given Linux commands.
#include <stdio.h>
#include <sys/types.h>
#include <unistd.h>
int main()
fork();
fork();
fork();
fork();
printf("Using fork() system call");
return 0;
output
Using fork() system call
Using fork() system call
Using fork() system call
Using fork() system call
Using fork() system call
Using fork() system call
Using fork() system call
Using fork() system call
Using fork() system call
Using fork() system call
Using fork() system call
Using fork() system call
Using fork() system call
Using fork() system call
Using fork() system call
Using fork() system call
EXPERIMENT 16
Write a C-program to fork a child process, print owner process ID and its parent
process ID.
#include<stdio.h>
#include <unistd.h>
int main()
{
int i;
printf("hello before fork \n");
printf("i : %d\n",i);
i=fork();
printf("\n");
if(i==0)
{
printf("Child has started\n\n");
printf("child printing first time \n");
printf("getpid : %d getppid : %d \n",getpid(),getppid());
sleep(5);
printf("\nchild printing second time \n");
printf("getpid : %d getppid : %d \n",getpid(),getppid());
}
else
{
printf("parent has started\n");
printf("getpid : %d getppid : %d \n",getpid(),getppid());
printf("\n");
printf("Hi after fork i : %d\n",i);
return 0;
output
[04mca8@LINTEL pp]$ ./a.out
hello before fork
i : 134514088
Child has started
child printing first time
getpid : 8354 getppid : 8353
parent has started
getpid : 8353 getppid : 5656
Hi after fork i : 8354
[04mca8@LINTEL pp]$
child printing second time
getpid : 8354 getppid : 1
Hi after fork i : 0
EXPERIMENT 17
Write a C-program to prompt the user for the name of the environment variable, check
its validity and print an appropriate message.
#include <stdio.h>
int main(int argc, char *argv[], char * envp[])
{
int i;
for (i = 0; envp[i] != NULL; i++)
printf("\n%s", envp[i]);
getchar();
return 0;
}
output
ALLUSERSPROFILE=C:\ProgramData
CommonProgramFiles=C:\Program Files\Common Files
HOMEDRIVE=C:
NUMBER_OF_PROCESSORS=2
OS=Windows_NT
PATHEXT=.COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH;.MSC
PROCESSOR_ARCHITECTURE=x86
PROCESSOR_IDENTIFIER=x86 Family 6 Model 42 Stepping 7, GenuineIntel
PROCESSOR_LEVEL=6
PROCESSOR_REVISION=2a07
ProgramData=C:\ProgramData
ProgramFiles=C:\Program Files
PUBLIC=C:\Users\Public
SESSIONNAME=Console
SystemDrive=C:
SystemRoot=C:\Windows
WATCOM=C:\watcom
windir=C:\Windows
EXPERIMENT 18
Write a C-program to READ details of N students such as student name, reg number,
semester and age. Find the eldest of them and display his details.
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
struct Student {
char* name;
int id;
char age;
};
int comparator(const void* p, const void* q)
{
return strcmp(((struct Student*)p)->name,
((struct Student*)q)->name);
}
int main()
{
int i = 0, n = 5;
struct Student arr[n];
arr[0].id = 1;
arr[0].name = "bd";
arr[0].age = 12;
arr[1].id = 2;
arr[1].name = "ba";
arr[1].age = 10;
arr[2].id = 3;
arr[2].name = "bc";
arr[2].age = 8;
arr[3].id = 4;
arr[3].name = "aaz";
arr[3].age = 9;
arr[4].id = 5;
arr[4].name = "az";
arr[4].age = 10;
printf("Unsorted Student Records:\n");
for (i = 0; i < n; i++) {
printf("Id = %d, Name = %s, Age = %d \n",
arr[i].id, arr[i].name, arr[i].age);
}
qsort(arr, n, sizeof(struct Student), comparator);
printf("\n\nStudent Records sorted by Name:\n");
for (i = 0; i < n; i++) {
printf("Id = %d, Name = %s, Age = %d \n",
arr[i].id, arr[i].name, arr[i].age);
}
return 0;
}
output
Unsorted Student Records:
Id = 1, Name = bd, Age = 12
Id = 2, Name = ba, Age = 10
Id = 3, Name = bc, Age = 8
Id = 4, Name = aaz, Age = 9
Id = 5, Name = az, Age = 10
Student Records sorted by Name:
Id = 4, Name = aaz, Age = 9
Id = 5, Name = az, Age = 10
Id = 2, Name = ba, Age = 10
Id = 3, Name = bc, Age = 8
Id = 1, Name = bd, Age = 12
