linux三剑客实战

拼搏现实的明天。 2021-11-11 13:48 348阅读 0赞

## 1.sed取ip地址 ##

①传统写法

[root@localhost cs]# ifconfig eth0 | sed -n '2p'
              inet addr:192.168.197.150  Bcast:192.168.197.255  Mask:255.255.255.0
    [root@localhost cs]# ifconfig eth0 | sed -n '2p'|sed 's/^.*dr://g'
    192.168.197.150  Bcast:192.168.197.255  Mask:255.255.255.0
    [root@localhost cs]# ifconfig eth0 | sed -n '2p'|sed 's/^.*dr://g'|sed 's/ Bcast.*$//g' 
    192.168.197.150
    [root@localhost cs]#

②  
sed -rn ：  
\-r代表拓展正则，后面不需要转义字符 \\ 来对有歧义的特殊符号进行转义，后面可以接拓展正则表达式  
\-n 取消默认输出  
^.*dr以任意字符开头匹配到dr结束  
Bcast.*$ 以Bcast起始一直到最后结束  
\\1 固定写法，代表（.\*）的内容

[root@localhost cs]# ifconfig|sed -rn 's/^.*dr:(.*) Bcast.*$/\1/gp'
    192.168.197.150 
    [root@localhost cs]#

③利用ifconfig eth0|sed -n '/inet addr:19/p’过滤出来这一行，然后再用/s\#\#\#g/进行替换

[root@localhost ~]# ifconfig eth0
    eth0      Link encap:Ethernet  HWaddr 00:0C:29:7C:5B:79  
              inet addr:192.168.197.150  Bcast:192.168.197.255  Mask:255.255.255.0
              inet6 addr: fe80::20c:29ff:fe7c:5b79/64 Scope:Link
              UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
              RX packets:87822 errors:0 dropped:0 overruns:0 frame:0
              TX packets:63769 errors:0 dropped:0 overruns:0 carrier:0
              collisions:0 txqueuelen:1000 
              RX bytes:72874461 (69.4 MiB)  TX bytes:27158178 (25.9 MiB)
    
    [root@localhost ~]# ifconfig eth0|sed -nr '/inet addr:19/s#^.*:(.*) Bca.*$#\1#p'
    192.168.197.150 
    [root@localhost ~]#

## 2.awk ##

注意：print外面的’\{ \}’ 必须存在

[root@localhost ~]# ifconfig eth0
    eth0      Link encap:Ethernet  HWaddr 00:0C:29:7C:5B:79  
              inet addr:192.168.197.150  Bcast:192.168.197.255  Mask:255.255.255.0
              inet6 addr: fe80::20c:29ff:fe7c:5b79/64 Scope:Link
              UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
              RX packets:87353 errors:0 dropped:0 overruns:0 frame:0
              TX packets:63516 errors:0 dropped:0 overruns:0 carrier:0
              collisions:0 txqueuelen:1000 
              RX bytes:72824853 (69.4 MiB)  TX bytes:27110624 (25.8 MiB)
    [root@localhost ~]# ifconfig eth0| awk -F '[:]' 'NR==2{print$2}'|awk -F'[ ]' '{print$1}'  
    192.168.197.150
    [root@localhost ~]# ifconfig eth0| awk -F '[ :]+' 'NR==2{print$4}'                      
    192.168.197.150

![在这里插入图片描述][20190807201516904.png]  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MjE5MzQ4OQ_size_16_color_FFFFFF_t_70]  
[图片链接地址文章][Link 1]

[20190807201516904.png]: /images/20211109/e6f9a2bbecbb42c6a9f0e1b36727d87f.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MjE5MzQ4OQ_size_16_color_FFFFFF_t_70]: /images/20211109/0800a13a640645da9e937cbc9c01539e.png
[Link 1]: https://blog.oldboyedu.com/swordsman-awk/