#!/bin/bash print_usage () { printf "please enter an inteper \n" } read -p "Please input first number:" firstnum while [ "echo "$firstnum" | sed -r 's#[^0-9]##g'" != "$firstnum" ] do print_usage read firstnum done read -p "Please input the operators:" operators while [ "$operators" != "+" ]&&[ "$operators" != "-" ]&&[ "$operators" != "*" ]&&[ "$operators" != "/" ] do read -p "please use + - * /" operators done read -p "Please input second number:" secondnum while [ "echo "$secondnum" | sed -r 's#[^0-9]##g'" != "$secondnum" ] do print_usage read secondnum done echo "${firstnum}${operators}${secondnum} =$((${firstnum}${operators}${secondnum}))" echo "$$" >/var/run/jsq.pid