shell文本处理工具-shell三剑客1-编程知识

shell脚本常用基础命令2

shell脚本常用基础命令

shell脚本常用基础命令2
一、grep用法
二、sed用法
- 2.1p参数（显示）n参数（只显示处理过的行）

文本处理三剑客：grep sed awk

一、grep用法

grep -E = egrep (扩展搜索正文表达式)
grep格式
grep 匹配条件处理文件(很多正文表达式用不了) |表示或者

[root@docker3 mnt]# grep "bash|root" passwd 
[root@docker3 mnt]# egrep "bash|root" passwd 
root:x:0:0:root:/root:/bin/bash
test:root:test
operator:x:11:0:operator:/root:/sbin/nologin
yan:x:1000:1000::/home/yan:/bin/bash
[root@docker3 mnt]# grep -E "bash|root" passwd 
root:x:0:0:root:/root:/bin/bash
test:root:test
operator:x:11:0:operator:/root:/sbin/nologin
yan:x:1000:1000::/home/yan:/bin/bash
[root@docker3 mnt]# grep -e bash -e root passwd 
root:x:0:0:root:/root:/bin/bash
test:root:test
operator:x:11:0:operator:/root:/sbin/nologin
yan:x:1000:1000::/home/yan:/bin/bash

grep开启的是贪婪模式，要是不匹配前面的<,不匹配后面>

[root@docker3 mnt]# grep -E "root" passwd 
root:x:0:0:root:/root:/bin/bash
test:root:test
chroot
rootch

[root@docker3 mnt]# grep -E "\<root" passwd 
root:x:0:0:root:/root:/bin/bash
test:root:test
rootch
operator:x:11:0:operator:/root:/sbin/nologin

[root@docker3 mnt]# grep -E "\<root\>" passwd 
root:x:0:0:root:/root:/bin/bash
test:root:test
operator:x:11:0:operator:/root:/sbin/nologin

grep 前面加数字,表示该关键字前面后面几行都显示出来

[root@docker3 mnt]# grep chroot passwd 
chroot
[root@docker3 mnt]# grep -2 chroot passwd 
test:root:test
TEST:ROOT:TEST
chroot
rootch
operator:x:11:0:operator:/root:/sbin/nologin

[root@docker3 mnt]# grep -A2 chroot passwd 
chroot
rootch
operator:x:11:0:operator:/root:/sbin/nologin
[root@docker3 mnt]# grep -B2 chroot passwd 
test:root:test
TEST:ROOT:TEST
chroot

显示匹配的在第几行

[root@docker3 mnt]# grep -n chroot passwd 
12:chroot

反向过滤，除了chroot其它行都过滤出来，展示部分。

[root@docker3 mnt]# grep -v chroot passwd 
root:x:0:0:root:/root:/bin/bash
bin:x:1:1:bin:/bin:/sbin/nologin
postfix:x:89:89::/var/spool/postfix:/sbin/nologin
tss:x:59:59:Account used by the trousers package to sandbox the tcsd daemon:/dev/null:/sbin/nologin
yan:x:1000:1000::/home/yan:/bin/bash

以^…开头，…￥以…结尾

[root@docker3 mnt]# grep -E "^root" passwd 
root:x:0:0:root:/root:/bin/bash
rootch
[root@docker3 mnt]# grep -E "bash$" passwd 
root:x:0:0:root:/root:/bin/bash
yan:x:1000:1000::/home/yan:/bin/bash

[root@docker3 mnt]# grep -E "ws" yan
ws
[root@docker3 mnt]# grep -E "w.s" yan
was
[root@docker3 mnt]# grep -E "w...s" yan
waaas
[root@docker3 mnt]# grep -E "w.*s" yan
ws
was
waaas
waaaas
waaaaas
wabababs
[root@docker3 mnt]# grep -E "w.?s" yan
ws
was
[root@docker3 mnt]# grep -E "w.+s" yan
was
waaas
waaaas
waaaaas
wabababs
[root@docker3 mnt]# grep -E "w.{3}s" yan
waaas
[root@docker3 mnt]# grep -E "w.{2,3}s" yan
waaas
[root@docker3 mnt]# grep -E "w.{,3}s" yan
ws
was
waaas
[root@docker3 mnt]# grep -E "w.{3,}s" yan
waaas
waaaas
waaaaas
wabababs
[root@docker3 mnt]# grep -E "wab{1,}s" yan
[root@docker3 mnt]# grep -E "w(ab){1,}s" yan
wabababs

脚本
请显示系统中能被su命令切换的用户名称
在这里插入图片描述

[root@docker3 mnt]# sh user_check.sh 
root
yan

二、sed用法

用来对文本的内容进行处理,修改的是模式空间（内存），真实的（磁盘中）
sed 参数命令处理对象
sed 参数处理对象 -f 处理规则文件

对字符的处理
p 显示
d 删除
a 添加
n 取消默认输出，sed默认会输出所有文本内容，使用-n参数后只显示处理过的行
i 插入，直接修改文件内容
c 替换
w 写入
r 整合文件

2.1p参数（显示）n参数（只显示处理过的行）

[root@docker3 mnt]# sed -n 5p passwd 
lp:x:4:7:lp:/var/spool/lpd:/sbin/nologin
[root@docker3 mnt]# vim rule
[root@docker3 mnt]# cat rule 
5p
[root@docker3 mnt]# sed -n -f rule passwd 
lp:x:4:7:lp:/var/spool/lpd:/sbin/nologin

[root@docker3 mnt]# sed  '5p' fstab 
1
#2
# /etc/fstab3
# Created by anaconda on Sun Mar 28 10:44:35 2021 4
#5
#5
# Accessible filesystems, by reference, are maintained under '/dev/disk'6
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info7
#8
/dev/mapper/rhel-root   /                       xfs     defaults        0 09
UUID=cf9ffcaf-d595-4545-9fd9-3573d573976e /boot  xfs  defaults        0 010
/dev/mapper/rhel-swap   swap                    swap    defaults        0 011
[root@docker3 mnt]# sed  -n '5p' fstab 
#5

[root@docker3 mnt]# sed  -n '3,5p' fstab 
# /etc/fstab3
# Created by anaconda on Sun Mar 28 10:44:35 2021 4
#5

[root@docker3 mnt]# sed  -n '3p;5p' fstab 
# /etc/fstab3
#5

#开头的行以及不是#开头的行

[root@docker3 mnt]# sed -n '/^#/p' fstab 
#2
# /etc/fstab3
# Created by anaconda on Sun Mar 28 10:44:35 2021 4
#5
# Accessible filesystems, by reference, are maintained under '/dev/disk'6
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info7
#8
[root@docker3 mnt]# sed -n '/^#/!p' fstab 
1
/dev/mapper/rhel-root   /                       xfs     defaults        0 09
UUID=cf9ffcaf-d595-4545-9fd9-3573d573976e /boot  xfs  defaults        0 010
/dev/mapper/rhel-swap   swap                    swap    defaults        0 011

^$空行

[root@docker3 mnt]# sed -n '/^#/!p' fstab | sed -n '/^$/!p'
1
/dev/mapper/rhel-root   /                       xfs     defaults        0 09
UUID=cf9ffcaf-d595-4545-9fd9-3573d573976e /boot  xfs  defaults        0 010
/dev/mapper/rhel-swap   swap                    swap    defaults        0 011

最后一行$p

[root@docker3 mnt]# sed -n '$p' fstab
/dev/mapper/rhel-swap   swap                    swap    defaults        0 011
[root@docker3 mnt]# sed -n '5,$p' fstab
#5
# Accessible filesystems, by reference, are maintained under '/dev/disk'6
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info7
#8
/dev/mapper/rhel-root   /                       xfs     defaults        0 09
UUID=cf9ffcaf-d595-4545-9fd9-3573d573976e /boot  xfs  defaults        0 010
/dev/mapper/rhel-swap   swap                    swap    defaults        0 011

显示行号，‘=’, '$='最后一行的行号（可以统计文件有多少行）

[root@docker3 mnt]# sed -n '$=' fstab 
11

[root@docker3 mnt]# sed -n -e '3p' -e '5p' fstab 
# /etc/fstab3
#5

d参数删除

[root@docker3 mnt]# sed 5d fstab 
1
#2
# /etc/fstab3
# Created by anaconda on Sun Mar 28 10:44:35 2021 4
# Accessible filesystems, by reference, are maintained under '/dev/disk'6
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info7
#8
/dev/mapper/rhel-root   /                       xfs     defaults        0 09
UUID=cf9ffcaf-d595-4545-9fd9-3573d573976e /boot  xfs  defaults        0 010
/dev/mapper/rhel-swap   swap                    swap    defaults        0 011

[root@docker3 mnt]# sed '3,5d' fstab 
1
#2
# Accessible filesystems, by reference, are maintained under '/dev/disk'6
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info7
#8
/dev/mapper/rhel-root   /                       xfs     defaults        0 09
UUID=cf9ffcaf-d595-4545-9fd9-3573d573976e /boot  xfs  defaults        0 010
/dev/mapper/rhel-swap   swap                    swap    defaults        0 011

[root@docker3 mnt]# sed '3d;5d' fstab 
1
#2
# Created by anaconda on Sun Mar 28 10:44:35 2021 4
# Accessible filesystems, by reference, are maintained under '/dev/disk'6
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info7
#8
/dev/mapper/rhel-root   /                       xfs     defaults        0 09
UUID=cf9ffcaf-d595-4545-9fd9-3573d573976e /boot  xfs  defaults        0 010
/dev/mapper/rhel-swap   swap                    swap    defaults        0 011

[root@docker3 mnt]# sed '/^#/d' fstab 
1
/dev/mapper/rhel-root   /                       xfs     defaults        0 09
UUID=cf9ffcaf-d595-4545-9fd9-3573d573976e /boot  xfs  defaults        0 010
/dev/mapper/rhel-swap   swap                    swap    defaults        0 011

a参数添加

[root@docker3 mnt]# sed '/^#/ahello' fstab 
1
#2
hello
# /etc/fstab3
hello
# Created by anaconda on Sun Mar 28 10:44:35 2021 4
hello
#5
hello
# Accessible filesystems, by reference, are maintained under '/dev/disk'6
hello
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info7
hello
#8
hello
/dev/mapper/rhel-root   /                       xfs     defaults        0 09
UUID=cf9ffcaf-d595-4545-9fd9-3573d573976e /boot  xfs  defaults        0 010
/dev/mapper/rhel-swap   swap                    swap    defaults        0 011

最后一行后面添加

[root@docker3 mnt]# sed '$ahello' fstab 
1
#2
# /etc/fstab3
# Created by anaconda on Sun Mar 28 10:44:35 2021 4
#5
# Accessible filesystems, by reference, are maintained under '/dev/disk'6
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info7
#8
/dev/mapper/rhel-root   /                       xfs     defaults        0 09
UUID=cf9ffcaf-d595-4545-9fd9-3573d573976e /boot  xfs  defaults        0 010
/dev/mapper/rhel-swap   swap                    swap    defaults        0 011
hello

[root@docker3 mnt]# sed '$ahello\nyan' fstab 
1
#2
# /etc/fstab3
# Created by anaconda on Sun Mar 28 10:44:35 2021 4
#5
# Accessible filesystems, by reference, are maintained under '/dev/disk'6
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info7
#8
/dev/mapper/rhel-root   /                       xfs     defaults        0 09
UUID=cf9ffcaf-d595-4545-9fd9-3573d573976e /boot  xfs  defaults        0 010
/dev/mapper/rhel-swap   swap                    swap    defaults        0 011
hello
yan

i参数插入 i是在最后一行前面，a是添加到最后一行

[root@docker3 mnt]# sed '$ihello\nyan' fstab 
1
#2
# /etc/fstab3
# Created by anaconda on Sun Mar 28 10:44:35 2021 4
#5
# Accessible filesystems, by reference, are maintained under '/dev/disk'6
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info7
#8
/dev/mapper/rhel-root   /                       xfs     defaults        0 09
UUID=cf9ffcaf-d595-4545-9fd9-3573d573976e /boot  xfs  defaults        0 010
hello
yan
/dev/mapper/rhel-swap   swap                    swap    defaults        0 011

[root@docker3 mnt]# sed '1ihello\nyan' fstab 
hello
yan
1
#2
# /etc/fstab3
# Created by anaconda on Sun Mar 28 10:44:35 2021 4
#5
# Accessible filesystems, by reference, are maintained under '/dev/disk'6
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info7
#8
/dev/mapper/rhel-root   /                       xfs     defaults        0 09
UUID=cf9ffcaf-d595-4545-9fd9-3573d573976e /boot  xfs  defaults        0 010
/dev/mapper/rhel-swap   swap                    swap    defaults        0 011

c参数替换

[root@docker3 mnt]# sed '/^#/chello' fstab 
1
hello
hello
hello
hello
hello
hello
hello
/dev/mapper/rhel-root   /                       xfs     defaults        0 09
UUID=cf9ffcaf-d595-4545-9fd9-3573d573976e /boot  xfs  defaults        0 010
/dev/mapper/rhel-swap   swap                    swap    defaults        0 011

w参数写入

[root@docker3 mnt]# sed '/^#/w file ' fstab 
[root@docker3 mnt]# cat file\  
#2
# /etc/fstab3
# Created by anaconda on Sun Mar 28 10:44:35 2021 4
#5
# Accessible filesystems, by reference, are maintained under '/dev/disk'6
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info7
#8
就是
[root@docker3 mnt]# sed -n '/^#/p' fstab > file
[root@docker3 mnt]# cat file
#2
# /etc/fstab3
# Created by anaconda on Sun Mar 28 10:44:35 2021 4
#5
# Accessible filesystems, by reference, are maintained under '/dev/disk'6
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info7
#8

[root@docker3 mnt]# cat yan
1
2
3
[root@docker3 mnt]# cat yan1
4
5
6
[root@docker3 mnt]# cat yan yan1
1
2
3
4
5
6
[root@docker3 mnt]# cat yan yan1 > file

倒叙

[root@docker3 mnt]# tac yan
3
2
1
[root@docker3 mnt]# tac yan yan1
3
2
1
6
5
4
[root@docker3 mnt]# tac yan1 yan
6
5
4
3
2
1

cat tac无法把文件yan1整合到数字1后面，可以正序也可以倒序
1r第一行后面

[root@docker3 mnt]# sed '1ryan1' yan
1
4
5
6
2
3

整合到某关键字后面

[root@docker3 mnt]# sed '/2/ryan1' yan
1
2
4
5
6
3

更改到原文件

[root@docker3 mnt]# sed '/2/ryan1' -i yan
[root@docker3 mnt]# cat yan
1
2
4
5
6
3

脚本
Apache_port.sh
此脚本接入数字
http的端口就改为此数字
假设selinux为关闭状态
在这里插入图片描述

[root@docker3 mnt]# sh Apacha_port.sh 
Error: Please input port number following script!!!
[root@docker3 mnt]# sh Apacha_port.sh 80
Error:Apache is not installed!!

双引号不能被引用变量，单引号会注释变量，所以Listen注意是要双引号
在这里插入图片描述

[root@docker3 mnt]# sh Apacha_port.sh 8080
[root@docker3 mnt]# netstat -antlp | grep 8080
tcp6       0      0 :::8080                 :::*                    LISTEN      4140/httpd

[root@docker3 mnt]# sh Apacha_port.sh 80
[root@docker3 mnt]# netstat -antlp | grep 80
tcp6       0      0 :::80                   :::*                    LISTEN      4172/httpd

sed字符替换
s是全文的行，g全文的列
部分展示 /表示分割符

[root@docker3 mnt]# sed 's/sbin/hello/g' passwd 
root:x:0:0:root:/root:/bin/bash
bin:x:1:1:bin:/bin:/hello/nologin
daemon:x:2:2:daemon:/hello:/hello/nologin
adm:x:3:4:adm:/var/adm:/hello/nologin
lp:x:4:7:lp:/var/spool/lpd:/hello/nologin
sync:x:5:0:sync:/hello:/bin/sync
sshd:x:74:74:Privilege-separated SSH:/var/empty/sshd:/hello/nologin
postfix:x:89:89::/var/spool/postfix:/hello/nologin
tss:x:59:59:Account used by the trousers package to sandbox the tcsd daemon:/dev/null:/hello/nologin
yan:x:1000:1000::/home/yan:/bin/bash
apache:x:48:48:Apache:/usr/share/httpd:/hello/nologin

[root@docker3 mnt]# sed 's/:/  /g' 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
operator  x  11  0  operator  /root  /sbin/nologin
games  x  12  100  games  /usr/games  /sbin/nologin

[root@docker3 mnt]# sed 's/:/  /' 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

[root@docker3 mnt]# sed '1,5s/:/  /' 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

[root@docker3 mnt]# sed '/lp/,/halt/s/:/  /g' 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
operator:x:11:0:operator:/root:/sbin/nologin

最后一行

[root@docker3 mnt]# sed '$s/:/  /g' passwd 
tss:x:59:59:Account used by the trousers package to sandbox the tcsd daemon:/dev/null:/sbin/nologin
yan:x:1000:1000::/home/yan:/bin/bash
apache  x  48  48  Apache  /usr/share/httpd  /sbin/nologin

[root@docker3 mnt]# sed '$s/:/  /g;s/sbin/hello/g'  passwd 
root:x:0:0:root:/root:/bin/bash
bin:x:1:1:bin:/bin:/hello/nologin
daemon:x:2:2:daemon:/hello:/hello/nologin
adm:x:3:4:adm:/var/adm:/hello/nologin
lp:x:4:7:lp:/var/spool/lpd:/hello/nologin
sync:x:5:0:sync:/hello:/bin/sync
shutdown:x:6:0:shutdown:/hello:/hello/shutdown

替换/，/需要转义，因为它是分割符

[root@docker3 mnt]# sed 's/:/  /g;s/\//##/g'  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

/表示分割符，可以换成@

[root@docker3 mnt]# sed 's@:@ @g;s@/@##@g' 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