shell工具-cut

cut

cut的工作就是“剪”，具体说就是在文件中负责剪切数据用的。cut命令从文件的每一行剪切字节、字符、和字段并将这些字节、字符和字段输出

基本用法

cut [参数] filename
# 说明：默认分割符是制表符

参数说明

选项参数	功能
-f	列号，提取第几列
-d	分隔符，按照指定分隔符分割列

案例实操

数据准备

[root@slave2 testshell]# touch cut.txt
[root@slave2 testshell]# vim cut.txt
dong shen
guan zhen
wo wo
lai lai
le le

切割cut.txt第一列

[root@slave2 testshell]# cut -d " " -f  cut.txt
dong
guan
wo
lai
le

切割cut.txt第二、三列

[root@slave2 testshell]# vim cut.txt
dong shen si
guan zhen chuan
wo wo wo
lai lai lai
le le le
[root@slave2 testshell]# cut -d " " -f , cut.txt
shen si
zhen chuan
wo wo
lai lai
le le

在cut.txt文件中切割出guan

[root@slave2 testshell]# cat cut.txt | grep ^guan
guan zhen chuan
[root@slave2 testshell]# cat cut.txt | grep ^guan | cut -d " " -f
guan

选取系统PATH变量值，第二个“:”开始后的所有路径

[root@slave2 testshell]# echo $PATH
/usr/local/src/kafka_2.-0.10.2.1/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/usr/local/src/scala-2.11./bin:/usr/local/src/spark-2.1.-bin-hadoop2./bin:/usr/local/src/jdk1..0_171/bin:/usr/local/src/hadoop-2.6./bin:/usr/local/src/zookeeper-3.4./bin:/root/bin
[root@slave2 testshell]# echo $PATH | cut -d : -f -
/usr/local/bin:/usr/sbin:/usr/bin:/usr/local/src/scala-2.11./bin:/usr/local/src/spark-2.1.-bin-hadoop2./bin:/usr/local/src/jdk1..0_171/bin:/usr/local/src/hadoop-2.6./bin:/usr/local/src/zookeeper-3.4./bin:/root/bin

切割ipconfig后打印的IP地址

[root@slave2 testshell]# ifconfig
ens33: flags=<UP,BROADCAST,RUNNING,MULTICAST>  mtu
        inet 192.168.242.22  netmask 255.255.255.0  broadcast 192.168.242.255
        inet6 fe80::c2d4::9c7c:ca0b  prefixlen   scopeid 0x20<link>
        ether :0c:::af:c5  txqueuelen   (Ethernet)
        RX packets   bytes  (1.9 GiB)
        RX errors   dropped   overruns   frame
        TX packets   bytes  (282.1 MiB)
        TX errors   dropped  overruns   carrier   collisions 

lo: flags=<UP,LOOPBACK,RUNNING>  mtu
        inet 127.0.0.1  netmask 255.0.0.0
        inet6 ::  prefixlen   scopeid 0x10<host>
        loop  txqueuelen   (Local Loopback)
        RX packets   bytes  (273.3 MiB)
        RX errors   dropped   overruns   frame
        TX packets   bytes  (273.3 MiB)
        TX errors   dropped  overruns   carrier   collisions
[root@slave2 testshell]# ifconfig ens33
ens33: flags=<UP,BROADCAST,RUNNING,MULTICAST>  mtu
        inet 192.168.242.22  netmask 255.255.255.0  broadcast 192.168.242.255
        inet6 fe80::c2d4::9c7c:ca0b  prefixlen   scopeid 0x20<link>
        ether :0c:::af:c5  txqueuelen   (Ethernet)
        RX packets   bytes  (1.9 GiB)
        RX errors   dropped   overruns   frame
        TX packets   bytes  (282.2 MiB)
        TX errors   dropped  overruns   carrier   collisions 

[root@slave2 testshell]# ifconfig ens33 | grep "inet "
        inet 192.168.242.22  netmask 255.255.255.0  broadcast 192.168.242.255
[root@slave2 testshell]# ifconfig ens33 | grep "inet " | cut -d " " -f
192.168.242.2