Shell Programming and Scripting

file=/etc/hosts
n=0
while IFS= read -r line
do
echo $n
n=$((n+1))
if [ $n == 3 ]
then
        echo $line
fi
done < "$file"

0
1
2
127.0.0.1 localhost.localdomain localhost
3

file=/etc/hosts
n=1
echo "enter which line you want to print"
read lin
while IFS= read -r line
do
if [[ $lin == $n ]];
then
echo $line
fi
n=$((n+1))
done < "$file"

sed -n 3p $file

awk NR==3 $file

if [ $n -eq 3 ]; then
  printf "%s\n" "$line"
fi

$ read -p "Enter line to read: " lNo; awk NR==$lNo /etc/hosts
Enter line to read: 3
127.0.0.1    localhost.localdomain        localhost