variables type
1)shell
2)system\/environment
3) userdefine variable<\/p>\n\n\n\n
Arithmetic calculation
Arithmetic Expansion ($((\u2026)))
Using expr Command<\/p>\n\n\n\n
echo “File Name: $0”
echo “First Parameter : $1”
echo “Second Parameter : $2”
echo “Quoted Values: $@”
echo “Quoted Values: $*”
echo “Total Number of Parameters : $#”<\/p>\n\n\n\n
for TOKEN in $*
do
echo $TOKEN
done<\/p>\n\n\n\n
echo “Enter first number”
read x
echo “Enter second number”
read y
sum=$(( $x + $y ))<\/p>\n\n\n\n
-eq Equality check
-ne Inequality check
-lt Less Than
-le Less Than or Equal
-gt Greater Than<\/p>\n\n\n\n
a=10
b=20<\/p>\n\n\n\n
if [ $a == $b ]
then
echo “a is equal to b”
else
echo “a is not equal to b”<\/p>\n\n\n\n
echo “enter no”
read n
if [ $((n%2))==0 ]
then
echo “The number is even.”
else
echo “The number is odd.”<\/p>\n\n\n\n
if [ case EXPRESSION in echo “enter your choice” $chmod +x aa.sh<\/p>\n\n\n\n echo “enter vowel” echo -n “Are you a student? [yes or no]: “ echo “Enter your lucky number” for i in {1..5} test 5 -gt 2 && echo “Yes”<\/p>\n\n\n\n for var in word1 word2 \u2026 wordN for (( initializer; condition; step )) until while for FILE in $HOME\/.bash* for var in 0 1 2 3 4 5 6 7 8 9 for (( i=1 ; i<=5 ; i++ )) for (( i=1 ; i<=5 ; i++ )) for i in {1..5} echo “Bash version ${BASH_VERSION}\u2026” echo “Enter a number (N):” echo “Enter the word to search for:” input_file=”in.txt” generate_password() password=$(generate_password)<\/p>\n\n\n\n directory=”$1″<\/p>\n\n\n\n if [ -z “$directory” ]; then if [ ! -d “$directory” ]; then host=”$1″ if [ $? -eq 0 ]; then a=0<\/p>\n\n\n\n until [ $a -gt 10 ] done<\/p>\n\n\n\n \/\/was multiplication table<\/p>\n\n\n\n echo “Enter a Number” while [ $i -le 10 ] rows=5 clear echo “enter the year”<\/p>\n\n\n\n read a<\/p>\n\n\n\n year= $a<\/p>\n\n\n\n a=$(( $a %4 ))<\/p>\n\n\n\n if [ $a -eq 0 ];<\/p>\n\n\n\n then else echo “Enter any number” if [[ ( $n -eq 15 || $n -eq 45 ) ]] echo “Enter your lucky number” if [ $n -eq 101 ]; else ========================================<\/p>\n\n\n\n echo “enter file name” function F1() echo “Enter directory name” Creating Functions Hello () Hello<\/p>\n\n\n\n Hello () Hello Zara Ali<\/p>\n\n\n\n Hello () { Hello Zara Ali<\/p>\n\n\n\n ret=$?<\/p>\n\n\n\n number_one () number_two () echo -n “Enter Left-End: “ is_prime() is_odd() add() add 3 4<\/p>\n\n\n\n multiply 3 4<\/p>\n\n\n\n add 5 4<\/p>\n\n\n\n ans=$?<\/p>\n\n\n\n math() math 5 10<\/p>\n\n\n\n Test for empty arguments: Use the -z operator to check if an argument is empty<\/p>\n\n\n\n function check_empty() check_empty “apple”<\/p>\n\n\n\n find_avg() function digital_clock compare() file1 = $1<\/p>\n\n\n\n file2 = $2<\/p>\n\n\n\n cmp $file1 $file2<\/p>\n\n\n\n if [ $file1 -eq $file2 ] which nano<\/p>\n\n\n\n undo -> mu ->alt->u variables type1)shell2)system\/environment3) userdefine variable Arithmetic calculationArithmetic Expansion ($((\u2026)))Using expr Command Using let Command !\/bin\/bash echo “File Name: $0”echo “First Parameter : $1”echo “Second Parameter : $2”echo “Quoted Values: $@”echo “Quoted Values: $*”echo “Total Number of Parameters : $#” !\/bin\/sh for TOKEN in $*doecho $TOKENdone echo $1 !\/bin\/bash echo “Enter first number”read xecho “Enter second number”read […]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-77","page","type-page","status-publish","hentry"],"aioseo_notices":[],"_hostinger_reach_plugin_has_subscription_block":false,"_hostinger_reach_plugin_is_elementor":false,"_links":{"self":[{"href":"https:\/\/mitalgoswami.in\/index.php?rest_route=\/wp\/v2\/pages\/77","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mitalgoswami.in\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/mitalgoswami.in\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/mitalgoswami.in\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/mitalgoswami.in\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=77"}],"version-history":[{"count":3,"href":"https:\/\/mitalgoswami.in\/index.php?rest_route=\/wp\/v2\/pages\/77\/revisions"}],"predecessor-version":[{"id":81,"href":"https:\/\/mitalgoswami.in\/index.php?rest_route=\/wp\/v2\/pages\/77\/revisions\/81"}],"wp:attachment":[{"href":"https:\/\/mitalgoswami.in\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=77"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}expr $a % 2<\/code> == 0 -a $a -gt 10 ]
then
echo “$a is even and greater than 10.”
else
echo “$a failed the test.”<\/p>\n\n\n\nfi<\/h2>\n\n\n\n
Pattern_Case_1)
STATEMENTS
;;
Pattern_Case_1)
STATEMENTS
;;
Pattern_Case_N)
STATEMENTS
;;
*)
STATEMENTS
;;<\/p>\n\n\n\nesac<\/h2>\n\n\n\n
filename:aa.sh<\/h2>\n\n\n\n
!\/bin\/bash<\/h1>\n\n\n\n
read mycase
case $mycase in
1) echo “You selected unix”;;
2) echo “You selected php”;;
3) echo “You selected java”;;
4) echo “You selected c++”;;
5) exit
esac<\/p>\n\n\n\nSave the script and make it executable.<\/h1>\n\n\n\n
$.\/aa.sh<\/h2>\n\n\n\n
!\/bin\/bash<\/h1>\n\n\n\n
read mycase
case $mycase in
‘a’) echo “vowel”;;
‘e’) echo “vowel”;;
‘i’) echo “vowel”;;
‘o’) echo “vowel”;;
‘u’) echo “vowel”;;
*) echo “consonent” ;;<\/p>\n\n\n\nesac<\/h2>\n\n\n\n
!\/bin\/bash<\/h1>\n\n\n\n
read response
case $response in<\/p>\n\n\n\n \"Y\" | \"y\" | \"YES\" | \"Yes\" | \"yes\")\n echo -n \"Yes, I am a student.\"\n ;;\n\n \"N\" | \"n\" | \"No\" | \"NO\" | \"no\" | \"nO\")\n echo -n \"No, I am not a student.\";\n\n ;;\n *) echo -n \"Invalid input\"\n ;;<\/code><\/pre>\n\n\n\nesac<\/h2>\n\n\n\n
!\/bin\/bash<\/h1>\n\n\n\n
read n
case $n in
101)
echo echo “You got 1stprize” ;;
510)
echo “You got 2nd prize” ;;
999)
echo “You got 3rd prize” ;;
*)
echo “Sorry,tryfor the next time” ;;
esac<\/p>\n\n\n\n
\n\n\n\n!\/bin\/bash<\/h1>\n\n\n\n
do
sleep $i &
done
echo “Background processes started\u2026”
wait
echo “All processes have completed!”
~<\/p>\n\n\n\n
\n\n\n\ntest 1 -lt 2 && echo “Yes”<\/h2>\n\n\n\n
do
Statement(s) to be executed for every word.
done<\/p>\n\n\n\nThe C-style Bash for loop<\/h2>\n\n\n\n
do
shell_COMMANDS
done<\/p>\n\n\n\n\/bin\/bash<\/h1>\n\n\n\n
do
done<\/p>\n\n\n\n\/bin\/bash<\/h1>\n\n\n\n
do
<\/p>\n\n\n\ndone<\/h2>\n\n\n\n
display all the files starting with .bash and available in your home<\/h1>\n\n\n\n
!\/bin\/sh<\/h1>\n\n\n\n
do
echo $FILE<\/p>\n\n\n\ndone<\/h2>\n\n\n\n
!\/bin\/sh<\/h1>\n\n\n\n
do
echo $var
done<\/p>\n\n\n\n
\n\n\n\n!\/bin\/bash<\/h1>\n\n\n\n
do
for (( j=1 ; j<=i ; j++ ))
do
echo -n “*”
done
echo ” “<\/p>\n\n\n\ndone<\/h2>\n\n\n\n
!\/bin\/bash<\/h1>\n\n\n\n
do
for (( j=1 ; j<=i ; j++ ))
do
echo -n “$i”
done
echo ” “<\/p>\n\n\n\ndone<\/h2>\n\n\n\n
!\/bin\/bash<\/h1>\n\n\n\n
do
echo “Welcome $i times”<\/p>\n\n\n\ndone<\/h2>\n\n\n\n
!\/bin\/bash<\/h1>\n\n\n\n
for i in {0..10..2} #{START..END..INCREMENT}
do
echo “Welcome $i times”<\/p>\n\n\n\ndone<\/h2>\n\n\n\n
Write a shell script that calculates the sum of integers from 1 to N using a loop.<\/h1>\n\n\n\n
!\/bin\/bash<\/h1>\n\n\n\n
read N
sum=0
for (( i=1; i<=$N; i++ )); do
sum=$((sum + i))
done<\/p>\n\n\n\necho “Sum of integers from 1 to $N is: $sum”<\/h2>\n\n\n\n
Create a script that searches for a specific word in a file and counts its occurrences.<\/h1>\n\n\n\n
!\/bin\/bash<\/h1>\n\n\n\n
read target_word
echo “Enter the filename:”
read filename
count=$(grep -o -w “$target_word” “$filename” | wc -l)<\/p>\n\n\n\necho “The word ‘$target_word’ appears $count times in ‘$filename’.”<\/h2>\n\n\n\n
Create a script that checks for and removes duplicate lines in a text file.<\/h1>\n\n\n\n
!\/bin\/bash<\/h1>\n\n\n\n
output_file=”output.txt”
sort “$input_file” | uniq > “$output_file”<\/p>\n\n\n\necho “Duplicate lines removed successfully.”<\/h2>\n\n\n\n
Write a script that generates a secure random password.<\/h1>\n\n\n\n
!\/bin\/bash<\/h1>\n\n\n\n
Function to generate a random password<\/h1>\n\n\n\n
{
tr -dc ‘A-Za-z0-9!@#$%^&*()_+{}[]’ < \/dev\/urandom | fold -w 12 | head -n 1
}<\/p>\n\n\n\nCall the function and store the generated password<\/h1>\n\n\n\n
echo “Generated password: $password”<\/h2>\n\n\n\n
Create a shell script that finds and lists all empty files in a directory.<\/h1>\n\n\n\n
!\/bin\/bash<\/h1>\n\n\n\n
echo “Usage: $0 “
exit 1
fi<\/p>\n\n\n\n
echo “Error: ‘$directory’ is not a valid directory.”
exit 1
fi
echo “Empty files in $directory:”<\/p>\n\n\n\nfind “$directory” -type f -empty<\/h2>\n\n\n\n
Create a script that checks if a network host is reachable.<\/h1>\n\n\n\n
!\/bin\/bash<\/h1>\n\n\n\n
if [ -z “$host” ]; then
echo “Usage: $0 “
exit 1
fi
ping -c 4 “$host”<\/p>\n\n\n\n
echo “$host is reachable.”
else
echo “$host is not reachable.”
fi<\/p>\n\n\n\n
\n\n\n\n\/bin\/bash<\/h1>\n\n\n\n
-gt is greater than operator<\/h1>\n\n\n\n
Iterate the loop until a is greater than 10<\/h1>\n\n\n\n
do<\/p>\n\n\n\n# Print the values\necho $a\n\n\n# increment the value\na=`expr $a + 1`<\/code><\/pre>\n\n\n\n
\n\n\n\n!\/bin\/bash<\/h1>\n\n\n\n
read n
i=1<\/p>\n\n\n\n
do
echo ” $n x $i = $(( n * i ))”
i=$(( i + 1 ))
done<\/p>\n\n\n\n
\n\n\n\n!\/bin\/bash<\/h1>\n\n\n\n
for((i=rows; i>=1; i–))
do
for((j=1; j<=i; j++))
do
echo -n “* “
done
echo<\/p>\n\n\n\ndone<\/h2>\n\n\n\n
!\/bin\/bash<\/h1>\n\n\n\n
p=$1
r=$2
n=$3
let int=expr $p \\* $r \\* $n<\/code>
int=expr $int \/ 100<\/code><\/p>\n\n\n\necho “simple interest , $int”<\/h2>\n\n\n\n
!\/bin\/bash<\/h1>\n\n\n\n
echo “$year is leap”<\/p>\n\n\n\n
echo “$year is not a leap year”<\/p>\n\n\n\nfi<\/h1>\n\n\n\n
!\/bin\/bash<\/h1>\n\n\n\n
read n<\/p>\n\n\n\n
then
echo “You won the game”
else
echo “You lost the game”<\/p>\n\n\n\nfi<\/h1>\n\n\n\n
!\/bin\/bash<\/h1>\n\n\n\n
read n<\/p>\n\n\n\n
then
echo “You got 1st prize”
elif [ $n -eq 510 ];
then
echo “You got 2nd prize”
elif [ $n -eq 999 ];
then
echo “You got 3rd prize”<\/p>\n\n\n\n
echo “Sorry, try for the next time”
fi<\/p>\n\n\n\n!\/bin\/bash<\/h1>\n\n\n\n
read fname
if [ -f $fname ]; then
echo “$fname file exist”
else
echo “sorry, $fname file does not exist”<\/p>\n\n\n\nfi<\/h1>\n\n\n\n
!\/bin\/bash<\/h1>\n\n\n\n
{
echo ‘I like bash programming’
}<\/p>\n\n\n\nF1<\/h1>\n\n\n\n
!\/bin\/bash<\/h1>\n\n\n\n
read ndir
if [ -d “$ndir” ]
then
echo “Directory exist”
elsemkdir $ndir<\/code>
echo “Directory created”<\/p>\n\n\n\nfi<\/h1>\n\n\n\n
function_name ()
{
list of commands<\/p>\n\n\n\n}<\/h2>\n\n\n\n
!\/bin\/sh<\/h1>\n\n\n\n
Define your function here<\/h1>\n\n\n\n
{
echo “Hello World”
}<\/p>\n\n\n\nInvoke your function<\/h1>\n\n\n\n
\n\n\n\n!\/bin\/sh<\/h1>\n\n\n\n
Define your function here<\/h1>\n\n\n\n
{
echo “Hello World $1 $2”
}<\/p>\n\n\n\nInvoke your function<\/h1>\n\n\n\n
\n\n\n\n!\/bin\/sh<\/h1>\n\n\n\n
Define your function here<\/h1>\n\n\n\n
echo “Hello World $1 $2”
return 10
}<\/p>\n\n\n\nInvoke your function<\/h1>\n\n\n\n
Capture value returnd by last command<\/h1>\n\n\n\n
echo “Return value is $ret”<\/h2>\n\n\n\n
!\/bin\/sh<\/h1>\n\n\n\n
Calling one function from another<\/h1>\n\n\n\n
{
echo “This is the first function speaking\u2026”
number_two
}<\/p>\n\n\n\n
{
echo “This is now the second function speaking\u2026”
}<\/p>\n\n\n\nCalling function one.<\/h1>\n\n\n\n
number_one<\/h2>\n\n\n\n
!\/bin\/bash<\/h1>\n\n\n\n
read le
echo -n “Enter Right-End: “
read ri<\/p>\n\n\n\n
{
if [ $1 -lt 2 ]; then
return
fi
ctr=0
for((i=2;i<$1;i++))
{
if [ $(( $1 % i )) -eq 0 ]; then
ctr=$(( ctr +1 ))
fi
}
if [ $ctr -eq 0 ]; then
printf “%d ” “$1”
fi
}
printf “Prime Numbers between %d and %d are: ” “$le” “$ri”
for((i=le;i<=ri;i++))
{
is_prime $i
}<\/p>\n\n\n\nprintf “\\n”<\/h2>\n\n\n\n
!\/bin\/bash<\/h1>\n\n\n\n
{
x=$1
if [ $((x%2)) == 0 ]; then
echo “Invalid Input”
exit 1
else
echo “Number is Odd”
fi
}<\/p>\n\n\n\nis_odd 64<\/h2>\n\n\n\n
!\/bin\/bash<\/h1>\n\n\n\n
{
return $(($1+$2))
}
multiply()
{
return $(($1*$2))
}<\/p>\n\n\n\nCall Addition for 3 and 4 == 7<\/h1>\n\n\n\n
Call multiplication for 3 and 4 == 12<\/h1>\n\n\n\n
Call Addition for 5 and 4 == 9<\/h1>\n\n\n\n
Store answer (always stores final function call returned value)<\/h1>\n\n\n\n
echo “$ans”<\/h2>\n\n\n\n
!\/bin\/bash<\/h1>\n\n\n\n
Name – math.sh<\/h1>\n\n\n\n
Purpose – Demo return value<\/h1>\n\n\n\n
————————————<\/h1>\n\n\n\n
user define function<\/h2>\n\n\n\n
{
local a=$1
local b=$2
local sum=$(( a + b))
return $sum
}<\/p>\n\n\n\ncall the math function with 5 and 10 as arguments<\/h2>\n\n\n\n
display back result (returned value) using $?<\/h2>\n\n\n\n
echo “5 + 10 = $?”<\/h2>\n\n\n\n
!\/bin\/bash<\/h1>\n\n\n\n
{
if [ -z “$1” ]; then
echo “Error: Argument is empty!”
return 1
fi
echo “Argument: $1”
}<\/p>\n\n\n\ncheck_empty “”<\/h2>\n\n\n\n
The following is one such function used to calculate the average of the given numbers.<\/h1>\n\n\n\n
!\/bin\/bash<\/h1>\n\n\n\n
{
len=$#
sum=0
for x in “$@”
do
sum=$((sum + x))
done
avg=$((sum\/len))
return $avg
}
find_avg 30 40 50 60
printf “%f” “$?”<\/p>\n\n\n\nprintf “\\n”<\/h2>\n\n\n\n
Below function creates a simple digital clock on terminal<\/h1>\n\n\n\n
T Displays the 24-hour clock (00-23) in the format equivalent to HH:MM:SS<\/h1>\n\n\n\n
!\/bin\/bash<\/h1>\n\n\n\n
{
clear
while [ 1 ]
do
date +’%T’
sleep 1
clear
done
}<\/p>\n\n\n\ndigital_clock<\/h2>\n\n\n\n
This is the second function<\/h2>\n\n\n\n
!\/bin\/bash<\/h1>\n\n\n\n
{<\/p>\n\n\n\n
then
echo “comparison is possible”
else
echo “compariosn is not possible”
fi<\/p>\n\n\n\n}<\/h2>\n\n\n\n
clear alt->t
copy ctrl+shift+c
paste ctrl+shift+v<\/p>\n","protected":false},"excerpt":{"rendered":"