linux sed

SED 替换功能：

1     sed -i ‘s#h#i#g‘ readme.txt

2      s  替换

g 全局替换

-i  修改文件

-n 取消默认输出

p 打印

[[email protected] cy]# ifconfig eth0| sed -n 2p
          inet addr:172.17.0.17  Bcast:172.17.15.255  Mask:255.255.240.0
[[email protected] cy]# ifconfig eth0| sed -n "2p"
          inet addr:172.17.0.17  Bcast:172.17.15.255  Mask:255.255.240.0

3     awk -F "[ :]+" ‘{print $3,$5,$7}‘ 3.txt |awk ‘{print $1}‘

172.17.0.17

2    [[email protected] cy]# ifconfig eth0 |grep "inet addr" |sed s#‘^.*r:##g‘|sed ‘s#Bc.*$##g‘