SHELL

shell script loop while process running

#!/bin/bash
x=1
while [ $x -le 5 ]
do
  echo "Welcome $x times"
  x=$(( $x + 1 ))
done

shell script loop while process running

#!/bin/bash
counter=$1
factorial=1
while [ $counter -gt 0 ]
do
   factorial=$(( $factorial * $counter ))
   counter=$(( $counter - 1 ))
done
echo $factorial

shell script loop while process running

while [ condition ]; do commands; done
while control-command; do COMMANDS; done

shell script loop while process running

while [ condition ]
do
   command1
   command2
   command3
done

shell script loop while process running

#!/bin/bash
FILE=$1
# read $FILE using the file descriptors
exec 3<&0
exec 0<$FILE
while read line
do
	# use $line variable to process line
	echo $line
done
exec 0<&3