And you also want to prevent `while` loop in shell script. See http://unix.stackexchange.com/q/169716/38906 http://unix.stackexchange.com/q/169716/38906 for mor

And you also want to prevent `while` loop in shell script. See http://unix.stackexchange.com/q/169716/38906 http://unix.stackexchange.com/q/169716/38906 for more details.