Unix Shell Programming Solved

7/27/2019 Unix Shell Programming Solved

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1. Write a shell script to print the users logged in, the current date and the calendar forthe year 2010.

echo "Program to print user logged in, current date and calender"echo "Following are the current users\n `who`"

echo "\nCurrent date is : `date`\n"set `date`echo "calendar of current year is \n `cal $6`"

Program to shell script to check the present working directory, then make a directory onthat location, then create 3 files in it and give executable permissions to them.

echo "present working directory is `pwd`\n"if [ -d newdir ]

then echo "newdir already exists"

elsemkdir newdirecho "newdir created"

fi

cd newdirecho "Current working director is `pwd`"

for file in file1 file2 file3do

echo $file|tee $file

done

3. shell script to take input for name, course and university and print it in the format I[name] study in [course] from [university].

if [ $# -ne 3 ]then

echo "Number of arguments required are three\n"echo "Enter your name\n"read nameecho "Enter the course\n"read courseecho "Enter the university\n"read university

elsename=$1course=$2university=$3

fi


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echo "I $name study in $course from $university"

4. shell script which creates one hard link and two soft links of a file.

echo "Enter name of the file\n"read fileif [ -e $file ]

thenecho "Creating hard link\n"ln $file $file"link1"

echo "Creating two soft links\n"ln -s $file $file"link2"ln -s $file $file"link3"

ls -li

elseecho "file not present"fi

5. #shell script that accepts two filenames and your script should copy file1 to file2 anddisplay both the files. (take input from keyboard and command line both).

if [ $# -ne 2 ]thenecho "Enter name of first file: "read file1echo "Enter name of second file: "read file2

elsefile1=$1file2=$2

ficp $file1 $file2

8. #shell script that should accept the output of the current date and print the output inthe form 2009 Oct Tue

echo "Current date is `date`"set `date`echo "$6 $2 $1"

9. #shell script that will display the files of the current directory and number of filesthrough positional arguments


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if [ -d $1 ]then echo "$1 is a directory"

elseecho "$1 is not present"

fi

cd $1echo "Following are the files present in $1 :\n"ls -lecho "Number of file are `ls|wc -l`"

10. #shell script using if, copy source to target, if it copies then echo copy processsuccessful else echo unable to copy

echo "Enter the source file: "

read snameecho "Enter the target program: "read tnamecp $sname $tname 2> errorif [ $? -eq 0 ]

then echo "Copy successful"else

echo "Unable to copy"fi

11. #shell script that will accept a number and then check if number is less than 10.Display the results accordinglyecho "Enter the number: "read numif [ num -lt 10 ]

then echo "$num is less than 10"else

echo "$num is greater or equal to 10"fi

12. #If Basic Salary=1500, then hra=500, da=98% of Basic.# If the employees basic salary is entered through the keyboard, then write a shell scriptto find the employees gross salary.echo "Enter your basic salary"read salaryif [ $salary -lt 1500 ]

then hra=`expr $salary \* 10 / 100`da=`expr $salary \* 90 / 100`

else


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hra=500da=èxpr $salary \* 98 / 100`

fi

gross=èxpr $salary + $hra + $da`

echo "Gross salary is: $gross"

13. #shell script where distance between two cities is entered from keyboard in kms andthen print that distance in meters and cms.echo "Enter the distance b/n two cities in kms: "read distanceecho "Distance in mtrs is : èxpr $distance \* 1000`\n"echo "Distance in cms is : èxpr $distance \* 100000`"

14. #shell script that perform all the mathematical operations on two numbers. (take input

from keyboard and command line both).if [ $# -ne 2 ]then echo "Enter the two numbers: "read num1 num2

elsenum1=$1num2=$2

fi

echo "Addition of numbers is èxpr $num1 + $num2`"echo "Subtraction of numbers is èxpr $num1 - $num2`"echo "Multiplication of numbers is èxpr $num1 \* $num2`"echo "Division of numbers is èxpr $num1 / $num2`"

15. #shell script which check whether the number is even or odd.echo "Enter the number: "read numif [ èxpr $num % 2` -eq 0 ]

then echo "$num is even number"else

echo "$num is odd number"fi

16. #shell script which displays the result of student as follows:# If %age is less then 40 then FAIL.# If %age is 40-50 then Third Division.# If %age is 50-60 then Second Division.# If %age is 60-75 then First Division,


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# If above 75 then Distinction.

echo "Enter the marks of the student: "read marksif [ $marks -gt 75 ]

then echo "Distinction"elif [ $marks -gt 59 ]then echo "First Division"

elif [ $marks -gt 49 ]then echo "Second division"

elif [ $marks -gt 39 ]then echo "Third division"

elseecho "Fail"

fi

17.. #shell script which accepts the age of a person and checks:# If age is less than 10 yrs then is not allowed.# If age is 10-18 then allowed to swim in junior pool.# If age >18 then senior pool.#

echo "Enter the age "read ageif [ $age -gt 18 ]

then echo "Senior pool allowed"elif [ $age -gt 9 ]

then echo "Junior pool allowed"else

echo "Not allowed"fi

18. #shell script that accepts a year and check whether it is a leap year or not.

echo "Enter the year "read yearif [ èxpr $year % 400 ` -eq 0 ]

then echo "$year is a leap year"elif [ èxpr $year % 4` -eq 0 ] && [ èxpr $year % 100` -ne 0 ]

then echo "$year is a leap year"else

echo "$year is not a leap year"fi


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19. #shell script which calculate area and perimeter of a rectangle when length andbreadth are entered into through keyboard and through command line

if [ $# -eq 2 ]then length=$1breadth=$2

elseecho "Enter length and breadth"read length breadth

fi

area=èxpr $length \* $breadth`perimeter=èxpr 2 \* $length + 2 \* $breadthècho "Area is $area\n"

echo "Perimeter is $perimeter"

20. #shell script which calculate sum of digits of a five-digit number and also checkswhether the number is a palindrome or not.

echo "Enter the five digit number"read numnum1=$numsum=0while [ $num -gt 0 ]do

n=èxpr $num % 10`sum=èxpr $sum + $n`num=èxpr $num / 10`rev=$rev$n

doneecho "Sum of digits is $sum"echo "Reverse of number is $rev"if [ $rev -eq $num1 ]

then echo "$num1 is a palindrome"else

echo "$num1 is not a palindrome"fi

21. #Make a menu driven shell script with# Option 1: Creates a dir d1/d2/d3 where all dir doesnt exist.# Option 2: Display some file f4 in the current dir.# Option 3: Check all the users who have logged in.#


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choice="4"echo "Enter choice 1 to create a directory\nEnter choice 2 to display file in current directory\nEnter choice 3 to check all logged in users\nEnter choice 4 to exit"

read choicewhile [ $choice != "4" ]do

case $choice in1) echo "Enter the directory to be created d1/d2/d3"

read dircase $dir ind1|d2|d3) if [ -d $dir ]

then echo "Directory $dir already present"elsemkdir $dir

fi ;;esac ;;2) echo "Enter the file to be displayed"

read filenameif [ -e $filename ]then echo "File contents are \n`cat $filename`"elseecho "File not present in directory"

fi ;;3) echo "Current users are `who`" ;;# *) $choice="y";;

esacecho "Enter your choice "read choice

done

22. #menu driven shell script with#Option 1: Check read permission. If it is there then display the file, if not then give theread permission.#Option 2: Check write permission. If it is there then append the file, if not then give thewrite permission.#Option 3: Check execute permission. If it is there then display the file, if not then say itis a text file.

echo "Enter the filename : "read filenameif [ ! -e $filename ]

then echo "$filename not present"else

echo "Enter choice 1 to check for read permission\n


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Enter choice 2 to check write permission\nEnter choice 3 to check execute permission\nEnter choice 4 to exit"read choicewhile [ $choice != "4" ]

docase $choice in1) if [ -r $filename ]

then echo "$filename is readable"elseecho "$filename not readable"fi ;;

2) if [ -w $filename ]then echo "$filename is writable"

echo "Enter text to be appended. To stop press CTRL + d "cat >> $filename

else echo "$filename not writable"fi ;;

3) if [ -x $filename ]then echo "$filename is executable"elseecho "$filename is not executable and a text file"

fi ;;

esacecho "Enter your choice "read choice

donefi

23. #shell script to check whether a file entered from command line is an ordinary file ordirectory. If it is a dir, then check the required permissions and create a dir in it, and inthat sub-dir, create a file. If it is a file, then append the file after checking thepermissions.

echo "Enter the filename : "read filenameif [ -f $filename ]

then echo "File is a regular file ."if [ -w $filename ]

then echo "Enter text to be appended. Press CTRL + d to exit"cat >> $filename

elseecho "File not editable"

fielse


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if [ -d $filename ]then echo "File is a directory"if [ -w $filename ]

then echo "Enter new file to be created in $filename"read f

cd $filenametouch $felse

echo "Directory does not have write permission"fi

fifi24. #shell script that uses for loop to display the names of files in the current directorywhich are only directory files

for file in *doif [ -d $file ]

then echo $filefi

done

25. #shell script to check the count of total number of arguments entered if number ofarguments is less than or equal to 5, then echo your name else echo error message, ie,invalid number of arguments. (Use while loop)echo $#while [ $# -gt 0 ]do

echo "Name"shift

done


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26 #Write a shell script where day(In Capitals) is entered in the command line. Check thestring and display:#a) If it is MON display Unix test,# If it is TUE display Computer Organization test,# If it is WED display System Programming test,

# If it is THUR display Maths test,# If it is FRI display Aptitude test,# then exit.

echo "Enter the day in capital letters, only first three letters : "read daycase $day in

MON) echo "Unix test" ;;TUE) echo "COA test" ;;WED) echo "System Programming test" ;;THUR) echo "Maths test" ;;

FRI) echo "Aptitude test" ;;*) exitesac

26.b) #Write a shell script where day(In Capitals) is entered in the command line. Checkthe string and display:#b) If it is MON | mon display Unix test,# If it is TUE | tue display Computer Organization test,# If it is WED | wed display System Programming test,# If it is THUR | thur display Maths test,# If it is FRI | fri display Aptitude test,# then exit.#echo "Enter the day in capital letters, only first three letters : "read daycase $day in

MON|mon) echo "Unix test" ;;TUE|tue) echo "COA test" ;;WED|wed) echo "System Programming test" ;;THUR|thur) echo "Maths test" ;;FRI|fri) echo "Aptitude test" ;;*) exit

esac

27) #Write table of 2, and 5 through two ways:#1) Take the number inside the script.#2) Through positional parameter.

if [ $# -eq 1 ]


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then num=$1else

echo "Enter the number 2 or 5 : "read num

fi

i=1while [ $i -lt 11 ]

doecho "$num * $i = èxpr $num \* $i`"i=èxpr $i + 1`

done

28) #Write a shell script which accepts number of arguments. If number of arguments isequal to 5 then only it should displays your name five times (You can try this, first, bydisplaying your name once)?

echo "Enter number of arguments : "read argswhile [ $args -gt 0 ]

doecho "name"args=èxpr $args - 1`

done

29) #Write a shell script to search whether the username passed on command line haslogged in or not, after each minute? If user has logged in display the message and exitotherwise display a message Not logged in Yet (i.e. The process will go inbackground).

who > userlistgrep "$1" userlistwhile [ $? -ne 0 ]do

sleep 60echo "$1 has not logged in"who > userlistgrep "$1" userlist

doneecho "$1 logged in"

30) #Write a shell script which scans your current directory and the files which endwith .doc, rename those files to .txt. Suppose: the current directory named UNIXcontains the file unix01doc then it should be renamed to unix01txt, similarly for all thefiles of that directory?


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for file in *.docdo

mv $file `basename $file doc`"txt"done

31) #Write a shell script that scans the current directory (or any path ) and the filesending with doc are to be moved to a new directory name "word assignment" and the fileending with .c (its dot c) are to be moved to a new directory named "c assignments"?

for file in *.docdoflag=1if [ $flag -eq 1 ];

then mkdir "word_assignment"flag=0

fimv $file "word_assignment"done

for file in *.cdoflag=1if [ $flag -eq 1 ];

then mkdir "c_assignment"flag=0

fimv $file "c_assignment"

done

32) #Write a shell script that scans the current directory & renames all the regular files &not the directory files to the name of the log name i.e. filename. student ?cd "c_assignment"for file in *

doif [ -d $file ]

then echo "$file is a directory"elif [ -f $file ] && [ ! -d $file ]

then mv $file $file".student"fi

done


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33) #Write a shell script that takes pattern and filename as command line arguments anddisplays the result appropriately i.e. pattern found/ pattern not found.pattern=$1fname=$2

grep "$1" $2

if [ $? -eq 0 ]then echo "$pattern found in $fname"

elseecho "$pattern not found in $fname"

fi

34) #Write a shell script where you check whether the name#a) begins with A and ends with t.#b) begins with S and ends with T.

#c) any word with fixed length of four characters.#

echo "Enter name\n"read namelength=`expr "$name" : '.*'`echo "length is $length"

case "$name" inA*t) echo "name starts with A and ends with t" ;;S*T) echo "name starts with S and ends with T" ;;*) if [ length -eq 4 ]

then echo "length of $name is 4"fi

esac

35) #Write a shell script where you can accept a word and echo the message whether thename begins with a vowel, consonant or a digit?

echo "Enter name\n"read name

case "$name" in[AaEeIiOoUu]*) echo "$name begins with a vowel" ;;[0-9]*) echo "$name begins with a digit" ;;[b-df-hj-np-tv-zB-DF-HJ-NP-TV-Z]*) echo "$name begins witha consonant" ;;

Esac


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36) #Write a shell script that computes the factorial of a given number.

echo "Enter the number "

read numprod=1

while [ $num -gt 0 ]do

prod=` expr $prod \* $num `num=` expr $num - 1 `

done

echo "Factorial of $num is $prod"

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Unix Shell Programming Solved