sed命令常见用法

sed -n 'num1p' file 选出行号为num1的行
sed -n 'num1,num2p' file 选出num1~num2行
sed -n 'num1,$p' file 选出num1行到文件末尾
grep -n '.*' file |sed 'num1p' -n 带行号的显示
sed  '/root/p' -n pp.txt 查找带root的行
/ /之间和grep 一样 有些正则 需加 -r 参数 类似 grep的 -E
-e 多个表达式 或的关系
sed -e '/pattern1/p' -e '/pattern2/p' -n
或者
sed '/pattern1/p;/pattern2/p' -n
sed '1,5d' 筛选除了1,5行的
cat -n pp.txt |sed -r '/mysql|root/d' 筛选出不含有 mysql或者 root的 行
sed 's/str1/str2/' file 在file里把 str1替换成str2 查找显示
sed 'num1,num2s/str1/str2/' file 在file的num1~num2把 str替换成str2
大小写转换
sed 's/[a-z]/u&/g' 1.txt         u ->upper
sed 's/[A-Z]/l&/g' 1.txt         l ->lower
-i 修改了重定向至文件

[root@bogon ~]# cat -n pp.txt 
     1  root:x:0:0:root:/root:/bin/bash
     2  #bin:x:1:1:bin:/bin:/sbin/nologin
     3  daemon:x:2:2:daemon:/sbin:/sbin/nologin
     4  #adm:x:3:4:adm:/var/adm:/sbin/nologin
     5  lp:x:4:7:lp:/var/spool/lpd:/sbin/nologin
     6  sync:x:5:0:sync:/sbin:/bin/sync
     7  #shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown
     8  halt:x:7:0:halt:/sbin:/sbin/halt
     9  mail:x:8:12:mail:/var/spool/mail:/sbin/nologin
    10  operator:x:11:0:#operator:/root:/sbin/nologin
    11  games:x:12:100:games:/usr/games:/sbin/nologin
    12  ftp:x:14:50:FTP User:/var/ftp:/sbin/nologin
    13  nobody:x:99:99:Nobody:/:/sbin/nologin
    14  avahi-autoipd:x:170:170:Avahi IPv4LL Stack:/var/lib/avahi-autoipd:/sbin/nologin
    15  dbus:x:81:81:System message bus:/:/sbin/nologin
    16  polkitd:x:999:998:User for polkitd:/:/sbin/nologin
    17  abrt:x:173:173::/etc/abrt:/sbin/nologin
    18  sssd:x:998:997:User for sssd:/:/sbin/nologin
    19  colord:x:997:995:User for colord:/var/lib/colord:/sbin/nologin
    20  ntp:x:38:38::/etc/ntp:/sbin/nologin

sed '2p' pp.txt

[root@bogon ~]# sed '2p' pp.txt 
root:x:0:0:root:/root:/bin/bash
#bin:x:1:1:bin:/bin:/sbin/nologin
#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
ftp:x:14:50:FTP User:/var/ftp:/sbin/nologin
nobody:x:99:99:Nobody:/:/sbin/nologin
avahi-autoipd:x:170:170:Avahi IPv4LL Stack:/var/lib/avahi-autoipd:/sbin/nologin
dbus:x:81:81:System message bus:/:/sbin/nologin
polkitd:x:999:998:User for polkitd:/:/sbin/nologin
abrt:x:173:173::/etc/abrt:/sbin/nologin
sssd:x:998:997:User for sssd:/:/sbin/nologin
colord:x:997:995:User for colord:/var/lib/colord:/sbin/nologin
ntp:x:38:38::/etc/ntp:/sbin/nologin

sed -n '2p' pp.txt

[root@bogon ~]# sed -n '2p' pp.txt 
#bin:x:1:1:bin:/bin:/sbin/nologin

sed不具有显示行号功能 配合grep
grep -n '.*' pp.txt |sed '2p' -n

[root@bogon ~]# grep -n '.*' pp.txt |sed '2p' -n
2:#bin:x:1:1:bin:/bin:/sbin/nologin
[root@bogon ~]# grep -n '.*' pp.txt |sed '2,5p' -n
2:#bin:x:1:1:bin:/bin:/sbin/nologin
3:daemon:x:2:2:daemon:/sbin:/sbin/nologin
4:#adm:x:3:4:adm:/var/adm:/sbin/nologin
5:lp:x:4:7:lp:/var/spool/lpd:/sbin/nologin

grep -n '.*' pp.txt|sed  -n '5,$p'

[root@bogon ~]# grep -n '.*' pp.txt|sed  -n '5,$p'
5:lp:x:4:7:lp:/var/spool/lpd:/sbin/nologin
6:sync:x:5:0:sync:/sbin:/bin/sync
7:#shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown
8:halt:x:7:0:halt:/sbin:/sbin/halt
9:mail:x:8:12:mail:/var/spool/mail:/sbin/nologin
10:operator:x:11:0:#operator:/root:/sbin/nologin
11:games:x:12:100:games:/usr/games:/sbin/nologin
12:ftp:x:14:50:FTP User:/var/ftp:/sbin/nologin
13:nobody:x:99:99:Nobody:/:/sbin/nologin
14:avahi-autoipd:x:170:170:Avahi IPv4LL Stack:/var/lib/avahi-autoipd:/sbin/nologin
15:dbus:x:81:81:System message bus:/:/sbin/nologin
16:polkitd:x:999:998:User for polkitd:/:/sbin/nologin
17:abrt:x:173:173::/etc/abrt:/sbin/nologin
18:sssd:x:998:997:User for sssd:/:/sbin/nologin
19:colord:x:997:995:User for colord:/var/lib/colord:/sbin/nologin
20:ntp:x:38:38::/etc/ntp:/sbin/nologin

grep -n '.*' pp.txt |sed '/root/p' -n

[root@bogon ~]# grep -n '.*' pp.txt |sed '/root/p' -n
1:root:x:0:0:root:/root:/bin/bash
10:operator:x:11:0:#operator:/root:/sbin/nologin

[root@bogon ~]# cat 1.txt 
rt
rot
root
ro t
[root@bogon ~]# sed '/ro{1,}t/p' -n -E 1.txt 
rot
root

查找含有 root或者ftp的行
grep '.*' -n pp.txt |sed -e '/root/p' -e '/ftp/p' -n

[root@bogon ~]# grep '.*' -n pp.txt |sed -e '/root/p' -e '/ftp/p' -n
1:root:x:0:0:root:/root:/bin/bash
10:operator:x:11:0:#operator:/root:/sbin/nologin
12:ftp:x:14:50:FTP User:/var/ftp:/sbin/nologin

[root@bogon ~]# cat 1.txt 
php
php js
js
python
[root@bogon ~]# sed -e '/php/p' -e '/js/p' -n 1.txt 
php
php js
php js
js
[root@bogon ~]# sed -e '/php/p' -e '/js/p'  1.txt 
php
php
php js
php js
php js
js
js
python
[root@bogon ~]# sed  '/php/p;/js/p'  1.txt -n
php
php js
php js
js

cat -n pp.txt |sed '1,5d'

[root@bogon ~]# cat -n pp.txt |sed '1,5d'
     6  sync:x:5:0:sync:/sbin:/bin/sync
     7  #shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown
     8  halt:x:7:0:halt:/sbin:/sbin/halt
     9  mail:x:8:12:mail:/var/spool/mail:/sbin/nologin
    10  operator:x:11:0:#operator:/root:/sbin/nologin
    11  games:x:12:100:games:/usr/games:/sbin/nologin
    12  ftp:x:14:50:FTP User:/var/ftp:/sbin/nologin
    13  nobody:x:99:99:Nobody:/:/sbin/nologin
    14  avahi-autoipd:x:170:170:Avahi IPv4LL Stack:/var/lib/avahi-autoipd:/sbin/nologin
    15  dbus:x:81:81:System message bus:/:/sbin/nologin
    16  polkitd:x:999:998:User for polkitd:/:/sbin/nologin
    17  abrt:x:173:173::/etc/abrt:/sbin/nologin
    18  sssd:x:998:997:User for sssd:/:/sbin/nologin
    19  colord:x:997:995:User for colord:/var/lib/colord:/sbin/nologin
    20  ntp:x:38:38::/etc/ntp:/sbin/nologin

不看#开头的注释
cat pp.txt |sed '/^#/d'

sed 's/php/python/' 1.txt
sed '1,3s/php/python/' 1.txt

[root@bogon ~]# cat 1.txt 
11111111
123php456
123456js
123456php
[root@bogon ~]# sed 's/php/python/' 1.txt 
11111111
123python456
123456js
123456python
[root@bogon ~]# sed '1,3s/php/python/' 1.txt 
11111111
123python456
123456js
123456php

如果字符串里有/，可使用别的分隔符

/mnt/hgfs/ 替换为 /usr/local/nginx/html

sed 's#/mnt/hgfs/#/usr/local/nginx/html/#' www.conf>www.conf

大小写转换
小写转大写
sed 's/[a-z]/u&/g' 1.txt
sed 's/[A-Z]/l&/g' 1.txt

[root@bogon ~]# cat 1.txt 
11111111
123php456
123456js
123456pHp

[root@bogon ~]# sed 's/[a-z]/u&/' 1.txt 
11111111
123Php456
123456Js
123456PHp
[root@bogon ~]# sed 's/[a-z]/u&/g' 1.txt 
11111111
123PHP456
123456JS
123456PHP
[root@bogon ~]# sed 's/[A-Z]/l&/g' 1.txt 
11111111
123php456
123456js
123456php

字符串位置替换

[root@bogon ~]# cat 1.txt 
a:b:c:d
a1:b1:c1:d1
a2:b2:c2:d2
a_: :c:dddd
[root@bogon ~]# sed -r 's/([^:]+)(:.*:)([^:]+$)/321/' 1.txt
d:b:c:a
d1:b1:c1:a1
d2:b2:c2:a2
dddd: :c:a_