Shell程序——全段IP扫描

#!/bin/bash

if [[ $1 == '' ]];then
    printf "用法：\n"
    printf "    sh test.sh {24位IP段}\n"
else
    IP=$1
    echo ${IP} > .ip
    cmd=$(cat .ip | awk -F '.' '{$NF="";print $0}')
    echo ${cmd} > .ip && sed -i "s/ /./g" .ip
    IPD=$(cat .ip)
    START=$(date +%d%M%S)
    printf "IP扫描开始: ${START} \n"
    for i in $(seq 255)
    do {
        ping -c 1 ${IPD}.$i >& /dev/null
        if [ $? -eq 0 ]; then
            echo "${IPD}.$i is Success!" >> Ping-Scan.log
        else
            echo "${IPD}.$i is Failed!" >> Ping-Scan.log
        fi
    } &
    done
    wait
    END=$(date +%d%M%S)
    TIME=$((${END}-${START}))
    printf "IP扫描结束：${END}\n"
    printf "程序执行结束,总耗时: ${TIME}s\n"
fi