实现自己的ip命令

#!/bin/bash#--------------------------------------#本脚本可以显示PC的ip地址，还可以配置ip和mask#日期：2016/7/24#作者：齐豪#--------------------------------------Usage(){    echo "usage: ./3.myip.sh [] or [-ip IP ADDR] [-mask MASK]"    exit}printIp(){    echo "NIC       IP Address"    echo "eth0      $(ifconfig eth0 | grep 'inet addr' | awk '{print $2}' | awk -F ":" '{print $2}')"    exit}changeIp(){    eval "ifconfig eth0 $1 netmask $2" #配置信息    echo "Setup completed"    exit}if [ -z $1 ]; then    printIp;elif [[ $1 = "-ip" && $3 = "-mask" ]]; then    changeIp $2 $4;else    Usage;fi