Shell Script Decision

#!/bin/sh

a=10
b=20

if [ $a == $b ]
then
echo "a is equal to b"
fi

if [ $a != $b ]
then
echo "a is not equal to b"
fi

---

#!/bin/sh

a=10
b=20

if [ $a == $b ]
then
echo "a is equal to b"
else
echo "a is not equal to b"
fi

---

#!/bin/sh

a=10
b=20

if [ $a == $b ]
then
echo "a is equal to b"
elif [ $a -gt $b ]
then
echo "a is greater than b"
elif [ $a -lt $b ]
then
echo "a is less than b"
else
echo "None of the condition met"
fi

---

#!/bin/sh

a=10
b=20

if [ $a == $b ]
then
echo "a is equal to b"
elif [ $a -gt $b ]
then
echo "a is greater than b"
elif [ $a -lt $b ]
then
echo "a is less than b"
else
echo "None of the condition met"
fi

#!/bin/sh

option="${1}" 
case ${option} in 
-f) FILE="${2}" 
    echo "File name is $FILE"
    ;; 
-d) DIR="${2}" 
    echo "Dir name is $DIR"
    ;; 
*)  
    echo "`basename ${0}`:usage: [-f file] | [-d directory]" 
    exit 1 # Command to come out of the program with status 1
    ;; 
esac