cut 命令

cut

-d 自定义分隔符，默认为制表符

-f 与-d一起使用，指定显示哪个区域

-

[root@salt-server-192 sh]# cat /etc/passwd
root:x:0:0:root:/root:/bin/bash
bin:x:1:1:bin:/bin:/sbin/nologin
daemon:x:2:2:daemon:/sbin:/sbin/nologin
adm:x:3:4:adm:/var/adm:/sbin/nologin
lp:x:4:7:lp:/var/spool/lpd:/sbin/nologin
sync:x:5:0:sync:/sbin:/bin/sync
shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown
halt:x:7:0:halt:/sbin:/sbin/halt
mail:x:8:12:mail:/var/spool/mail:/sbin/nologin
uucp:x:10:14:uucp:/var/spool/uucp:/sbin/nologin
operator:x:11:0:operator:/root:/sbin/nologin
games:x:12:100:games:/usr/games:/sbin/nologin
gopher:x:13:30:gopher:/var/gopher:/sbin/nologin
ftp:x:14:50:FTP User:/var/ftp:/sbin/nologin
nobody:x:99:99:Nobody:/:/sbin/nologin
vcsa:x:69:69:virtual console memory owner:/dev:/sbin/nologin
saslauth:x:499:76:Saslauthd user:/var/empty/saslauth:/sbin/nologin
postfix:x:89:89::/var/spool/postfix:/sbin/nologin
sshd:x:74:74:Privilege-separated SSH:/var/empty/sshd:/sbin/nologin
ntp:x:38:38::/etc/ntp:/sbin/nologin

[root@localhost sh]# cut -d: -f 3 /etc/passwd 
0
1
2
3
4
5
6
7
8
10
11
12
13
14
99
69
499
89
74
38

// 以冒号为分隔符，取第三段的字符

[root@localhost sh]# cat /etc/passwd | cut -d : -f 5
root
bin
daemon
adm
lp
sync
shutdown
halt
mail
uucp
operator
games
gopher
FTP User
Nobody
virtual console memory owner
Saslauthd user

Privilege-separated SSH

// 以冒号为分隔符，取第五段的字符

[root@localhost sh]# cat /etc/passwd | cut -d : -f 3,4,5  
0:0:root
1:1:bin
2:2:daemon
3:4:adm
4:7:lp
5:0:sync
6:0:shutdown
7:0:halt
8:12:mail
10:14:uucp
11:0:operator
12:100:games
13:30:gopher
14:50:FTP User
99:99:Nobody
69:69:virtual console memory owner
499:76:Saslauthd user
89:89:
74:74:Privilege-separated SSH
38:38:

[root@localhost sh]# cat /etc/passwd | cut -d : -f 3-5  
0:0:root
1:1:bin
2:2:daemon
3:4:adm
4:7:lp
5:0:sync
6:0:shutdown
7:0:halt
8:12:mail
10:14:uucp
11:0:operator
12:100:games
13:30:gopher
14:50:FTP User
99:99:Nobody
69:69:virtual console memory owner
499:76:Saslauthd user
89:89:
74:74:Privilege-separated SSH
38:38:

//以冒号为分隔符，取每一行第3-5段的字符

-c 按字符取

[root@localhost sh]# cut -c 1 /etc/passwd 
r
b
d
a
l
s
s
h
m
u
o
g
g
f
n
v
s
p
s
n

//取出每一行的第一个字符

取出每一行第10个字符到每行结束

[root@localhost sh]# cut -c 10- /etc/passwd
0:root:/root:/bin/bash
:bin:/bin:/sbin/nologin
2:2:daemon:/sbin:/sbin/nologin
:adm:/var/adm:/sbin/nologin
lp:/var/spool/lpd:/sbin/nologin
0:sync:/sbin:/bin/sync
x:6:0:shutdown:/sbin:/sbin/shutdown
0:halt:/sbin:/sbin/halt
12:mail:/var/spool/mail:/sbin/nologin
:14:uucp:/var/spool/uucp:/sbin/nologin
x:11:0:operator:/root:/sbin/nologin
2:100:games:/usr/games:/sbin/nologin
13:30:gopher:/var/gopher:/sbin/nologin
50:FTP User:/var/ftp:/sbin/nologin
99:99:Nobody:/:/sbin/nologin
:69:virtual console memory owner:/dev:/sbin/nologin
x:499:76:Saslauthd user:/var/empty/saslauth:/sbin/nologin
:89:89::/var/spool/postfix:/sbin/nologin
:74:Privilege-separated SSH:/var/empty/sshd:/sbin/nologin
38::/etc/ntp:/sbin/nologin
[root@localhost sh]# cut -c 5- /etc/passwd  
:x:0:0:root:/root:/bin/bash
x:1:1:bin:/bin:/sbin/nologin
on:x:2:2:daemon:/sbin:/sbin/nologin
x:3:4:adm:/var/adm:/sbin/nologin
:4:7:lp:/var/spool/lpd:/sbin/nologin
:x:5:0:sync:/sbin:/bin/sync
down:x:6:0:shutdown:/sbin:/sbin/shutdown
:x:7:0:halt:/sbin:/sbin/halt
:x:8:12:mail:/var/spool/mail:/sbin/nologin
:x:10:14:uucp:/var/spool/uucp:/sbin/nologin
ator:x:11:0:operator:/root:/sbin/nologin
s:x:12:100:games:/usr/games:/sbin/nologin
er:x:13:30:gopher:/var/gopher:/sbin/nologin
x:14:50:FTP User:/var/ftp:/sbin/nologin
dy:x:99:99:Nobody:/:/sbin/nologin
:x:69:69:virtual console memory owner:/dev:/sbin/nologin
auth:x:499:76:Saslauthd user:/var/empty/saslauth:/sbin/nologin
fix:x:89:89::/var/spool/postfix:/sbin/nologin
:x:74:74:Privilege-separated SSH:/var/empty/sshd:/sbin/nologin
x:38:38::/etc/ntp:/sbin/nologin
[root@localhost sh]# cut -c 5- /etc/passwd 
:x:0:0:root:/root:/bin/bash
x:1:1:bin:/bin:/sbin/nologin
on:x:2:2:daemon:/sbin:/sbin/nologin
x:3:4:adm:/var/adm:/sbin/nologin
:4:7:lp:/var/spool/lpd:/sbin/nologin
:x:5:0:sync:/sbin:/bin/sync
down:x:6:0:shutdown:/sbin:/sbin/shutdown
:x:7:0:halt:/sbin:/sbin/halt
:x:8:12:mail:/var/spool/mail:/sbin/nologin
:x:10:14:uucp:/var/spool/uucp:/sbin/nologin
ator:x:11:0:operator:/root:/sbin/nologin
s:x:12:100:games:/usr/games:/sbin/nologin
er:x:13:30:gopher:/var/gopher:/sbin/nologin
x:14:50:FTP User:/var/ftp:/sbin/nologin
dy:x:99:99:Nobody:/:/sbin/nologin
:x:69:69:virtual console memory owner:/dev:/sbin/nologin
auth:x:499:76:Saslauthd user:/var/empty/saslauth:/sbin/nologin
fix:x:89:89::/var/spool/postfix:/sbin/nologin
:x:74:74:Privilege-separated SSH:/var/empty/sshd:/sbin/nologin
x:38:38::/etc/ntp:/sbin/nologin

 取每一行 第一个字符到第5个字符

[root@localhost sh]# cut -c -5 /etc/passwd
root:
bin:x
daemo
adm:x
lp:x:
sync:
shutd
halt:
mail:
uucp:
opera
games
gophe
ftp:x
nobod
vcsa:
sasla
postf
sshd:
ntp:x

[root@localhost sh]# cut -c 1-5 /etc/passwd 
root:
bin:x
daemo
adm:x
lp:x:
sync:
shutd
halt:
mail:
uucp:
opera
games
gophe
ftp:x
nobod
vcsa:
sasla
postf
sshd:
ntp:x

取第2行-第4行字符

[root@localhost sh]# cut -c 2-4 /etc/passwd
oot
in:
aem
dm:
p:x
ync
hut
alt
ail
ucp
per
ame
oph
tp:
obo
csa
asl
ost
shd
tp: