提示用戶輸入網卡的名字，然後我們用腳本輸出網卡的ip

#!/bin/bash/ read -p "請輸入網卡名稱：" a if [ -n "$a" ] then ifconfig $a &> /dev/null if [ $? -eq 0 ] then ifconfig $a | awk '{printf $2 "\n"}' | egrep "([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])\.(([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0 -9]|25[0-5])\.){2}([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])" else echo "該網卡不存在" fi else echo "網卡名稱不能爲空" fi