Linux shell script read file line by line All In One

Linux shell 脚本逐行读取文件

I just want to replace thegrep command, and filter out the real IP address 192.168.18.195 with native shell syntax.

#!/usr/bin/env bash

IPs=$(ifconfig | grep -oE '192\.168\.(1?[0-9][0-9]?|2[0-4][0-9]|25[0-5])\.([2-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-4])\b')
echo $IPs
# 192.168.18.195

en1: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 1500
        options=6463<RXCSUM,TXCSUM,TSO4,TSO6,CHANNEL_IO,PARTIAL_CSUM,ZEROINVERT_CSUM>
        ether a4:83:e7:91:62:79 
        inet6 fe80::1ca2:3b0a:df9d:465f%en1 prefixlen 64 secured scopeid 0x7 
        inet 192.168.18.195 netmask 0xffffff00 broadcast 192.168.18.255
        inet6 fd80:eae6:1258:0:37:7544:1d1:7b08 prefixlen 64 autoconf secured 
        nd6 options=201<PERFORMNUD,DAD>
        media: autoselect
        status: active

https://gist.github.com/xgqfrms/a9e98b17835ddbffab07dde84bd3caa5

IP

while..do..done bash loop

# 多个命令写在同一行上，需要使用 `;` 符号分割
while read -r line; do COMMAND; done < input.file

ip-filter.sh

#!/usr/bin/env bash

# 写死文件的绝对路径 

标签：shell,script,read,ip,filter,file,line	

From： https://www.cnblogs.com/xgqfrms/p/17362135.html