#!/bin/bash #provide one word/sentence as an argument to the script. #If in that sentence will be ip addresss, find out, if that #ip address is reachable or not. #argument check if [ $# -ne 1 ]; then echo "Provide exactly one argument e.g. $0 argument" exit 1 fi VAR1=$1 #ip address regex REGEX="[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[[:digit:]]{1,3}" #regex check if ! [[ $VAR1 =~ $REGEX ]]; then echo "No IP address provided" exit 2 fi IP=${BASH_REMATCH[0]} #find if ip address is reachable or not ping -c4 $IP 1>/dev/null #1>/dev/null #It will redirect standard output and prevent #any output to print on screen. if [ $? -eq 0 ]; then STATUS="ALIVE" else STATUS="DEAD" fi echo "IP found: $IP ($STATUS)"