sed
命令
p 打印匹配行
[root@teacher test]# sed '/north/p' datafile
northwest NW Charles Main 3.0 .98 3 34
northwest NW Charles Main 3.0 .98 3 34
western WE Sharon Gray 5.3 .97 5 23
southwest SW Lewis Dalsass 2.7 .8 2 18
southern SO Suan Chin 5.1 .95 4 15
southeast SE Patricia Hemenway 4.0 .7 4 17
eastern EA TB Savage 4.4 .84 5 20
northeast NE AM Main Jr. 5.1 .94 3 13
northeast NE AM Main Jr. 5.1 .94 3 13
western WE Sharon Gray 5.3 .97 5 23
north NO Margot Weber 4.5 .89 5 9
north NO Margot Weber 4.5 .89 5 9
central CT Ann Stephens 5.7 .94 5 13
[root@teacher test]# sed -n '/north/p' datafile
northwest NW Charles Main 3.0 .98 3 34
northeast NE AM Main Jr. 5.1 .94 3 13
north NO Margot Weber 4.5 .89 5 9
[root@teacher test]# sed -n '/west/,/east/p' datafile
[root@teacher test]# sed -n '1p' datafile
northwest NW Charles Main 3.0 .98 3 34
[root@teacher test]# head -n 1 datafile
northwest NW Charles Main 3.0 .98 3 34
[root@teacher test]# sed -n '$p' datafile
central CT Ann Stephens 5.7 .94 5 13
[root@teacher test]# tail -n 1 datafile
central CT Ann Stephens 5.7 .94 5 13
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d 删除匹配行
[root@teacher test]# sed '/north/d' datafile
western WE Sharon Gray 5.3 .97 5 23
southwest SW Lewis Dalsass 2.7 .8 2 18
southern SO Suan Chin 5.1 .95 4 15
southeast SE Patricia Hemenway 4.0 .7 4 17
eastern EA TB Savage 4.4 .84 5 20
western WE Sharon Gray 5.3 .97 5 23
central CT Ann Stephens 5.7 .94 5 13
[root@teacher test]# sed '1d' datafile
western WE Sharon Gray 5.3 .97 5 23
southwest SW Lewis Dalsass 2.7 .8 2 18
southern SO Suan Chin 5.1 .95 4 15
southeast SE Patricia Hemenway 4.0 .7 4 17
eastern EA TB Savage 4.4 .84 5 20
northeast NE AM Main Jr. 5.1 .94 3 13
western WE Sharon Gray 5.3 .97 5 23
north NO Margot Weber 4.5 .89 5 9
central CT Ann Stephens 5.7 .94 5 13
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s 查找替换
/定址/s/匹配模式/替换内容/标记
匹配模式： 正则表达式
标记： num 替换第几次出现的模式
p 打印替换内容
w 另存
g 全局替换
[root@teacher test]# sed 's/root/ROOT/g' passwd
[root@teacher test]# sed -n 's/root/ROOT/gp' passwd
ROOT:x:0:0:ROOT:/ROOT:/bin/bash
roooot:x:0:0:ROOT:/ROOT:/bin/bash
ROOTooo:x:0:0:/bin/bash:arooootbc
ro:x:0:0:ROOT:/ROOT:/bin/bash
operator:x:11:0:operator:/ROOT:/sbin/nologin
[root@teacher test]# sed -n '1s/root/ROOT/gp' passwd
ROOT:x:0:0:ROOT:/ROOT:/bin/bash
[root@teacher test]# sed -n '/roooot:/s/root/ROOT/gp' passwd
roooot:x:0:0:ROOT:/ROOT:/bin/bash
[root@teacher test]# sed -n '/r\(o\)\1\1\1t:/s/root/ROOT/gp' passwd
roooot:x:0:0:ROOT:/ROOT:/bin/bash
[root@teacher test]# sed -n '/NW/s/west/north/p' datafile
[root@teacher test]# sed -n 's/root/**&**/p' passwd
**root**:x:0:0:root:/root:/bin/bash
roooot:x:0:0:**root**:/root:/bin/bash
[root@teacher test]# sed -n 's/root/hello&/gp' passwd
[root@teacher test]# sed -n 's/root/hello&/gp' passwd
helloroot:x:0:0:helloroot:/helloroot:/bin/bash
roooot:x:0:0:helloroot:/helloroot:/bin/bash
[root@teacher test]# sed -n 's/root/ROOT/2p' passwd
root:x:0:0:ROOT:/root:/bin/bash
roooot:x:0:0:root:/ROOT:/bin/bash
[root@teacher test]# sed -n 's/root/ROOT/w /test/file2' passwd
You have new mail in /var/spool/mail/root
[root@teacher test]# cat /test/file2
ROOT:x:0:0:root:/root:/bin/bash
roooot:x:0:0:ROOT:/root:/bin/bash
练习： 把/etc/vsftpd/vsftpd.conf 里面的 #anon_upload_enable=YES 注释去掉
方法1 # sed -n 's/#anon_upload_enable=YES/anon_upload_enable=YES/p' /etc/vsftpd/vsftpd.conf
anon_upload_enable=YES
方法2 [root@teacher test]# sed -n '/#anon_upload_enable=YES/s/^#//p' /etc/vsftpd/vsftpd.conf
anon_upload_enable=YES
方法3 [root@teacher test]# sed -n 's/#\(anon_upload_enable=YES\)/\1/p' /etc/vsftpd/vsftpd.conf
anon_upload_enable=YES
方法4 [root@teacher test]# sed -n 's/\(#\)\(anon_upload_enable=YES\)/\2/p' /etc/vsftpd/vsftpd.conf
anon_upload_enable=YES
[root@teacher test]#
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r 读入文件的内容
[root@teacher test]# cat a1
hello
hello2
# cat a2
tom
mike
[root@teacher test]# sed 'r a2' a1
hello
tom
mike
hello2
tom
mike
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w 另存为
# sed '1,3w file2' passwd
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a 在匹配行的下面添加内容
[root@teacher test]# sed '1a hello all' passwd
root:x:0:0:root:/root:/bin/bash
hello all
# sed -n '/#anon_upload_enable=YES/a anon_upload_enable=YES' /etc/vsftpd/vsftpd.conf
# sed '/^north/a the north has moved' datafile
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i 在匹配行的上面添加内容
[root@teacher test]# sed '1i hello all' passwd
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c 本行替换
# sed '1c dajihao' passwd|less
# sed '/^north/c he has gone' datafile
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y 按照位置替换
# sed 'y/abcdefghijklmnopqrstuvwxyz/zyxwvutsrqponmlkjihgfedcba/' s1
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；；； 多点编辑
-e '' -e ''
# sed -e 'p' -e 'p' s1
# sed 'p;p;p' s1
练习： 把/etc/ssh/sshd_config 87行注释去掉，88行加上注释
# vim /etc/ssh/sshd_config
87 #UsePAM no
88 UsePAM yes
[root@teacher test]# sed -e 's/#\(UsePAM no\)/\1/' -e 's/\(UsePAM yes\)/#\1/' /etc/ssh/sshd_config
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-r 扩展正则
# sed 's/^\(.\)\(.\)/\1/' s1
# sed -r 's/^(.)(.)/\1/' s1
# cat -n passwd | sed -n '5~5p'
5 bin:x:1:1:bin:/bin:/sbin/nologin
10 shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown
15 operator:x:11:0:operator:/root:/sbin/nologin
20 nscd:x:28:28:NSCD Daemon:/:/sbin/nologin
25 pcap:x:77:77::/var/arpwatch:/sbin/nologin
30 rpcuser:x:29:29:RPC Service User:/var/lib/nfs:/sbin/nologin
35 gdm:x:42:42::/var/gdm:/sbin/nologin
40 tomson:x:503:500::/home/tomson:/bin/bash
45 u3:x:1001:1001::/home/u3:/bin/bash
50 tom:x:1006:1007::/home/tom:/bin/bash
55 s1:x:1008:1009::/rhome/s1:/bin/bash
60 s6:x:1013:1014::/rhome/s6:/bin/bash
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n 处理匹配的下一行
# vim a3
1
2
3
4
5
6
7
8
[root@teacher test]# sed '3n; s/[0-9]/A/' a3
A
A
3
A
A
A
A
A
[root@teacher test]# sed '5n; s/[0-9]/A/' a3
A
A
A
A
5
A
A
A
[root@teacher test]# sed '2n;5n; s/[0-9]/A/' a3
A
2
A
A
5
A
A
A
[root@teacher test]# sed 's/[0-9]/A/;2n;5n;s/A/B/' a3
B
A
3
B
A
6
B
B
[root@teacher test]# sed 's/[0-9]/A/;2n;5n;s/[0-9]/B/' a3
A
A
B
A
A
B
A
A
------------------------------------
模式空间：PATT，处理文件的内容，对输入行使用命令进行处理
保留空间：HOLD，默认有一个空行，保存已经处理过的输入行的空间，也在内存上。
h：将模式空间的内容，复制到保留空间，覆盖原来的内容
H：将模式空间的内容，追加到保留空间，原内容保留
g：将保留空间的内容，复制到模式空间，覆盖原来的内容
G：将保留空间的内容，追加到模式空间，原内容保留
x：交换模式空间和保留空间的内容
# vim a5
this is a good idea.
no, it is'nt.
good day.
# sed -e '1h' -e '$G' a5
this is a good idea.
no, it is'nt.
good day.
this is a good idea.
# sed -e '1h' -e '$g' a5
this is a good idea.
no, it is'nt.
this is a good idea.
# sed -e '1h;1d' -e '$G' a5
no, it is'nt.
good day.
this is a good idea.
[root@teacher test]# sed -e '/northeast/H' -e '$G' datafile
northwest NW Charles Main 3.0 .98 3 34
western WE Sharon Gray 5.3 .97 5 23
southwest SW Lewis Dalsass 2.7 .8 2 18
southern SO Suan Chin 5.1 .95 4 15
southeast SE Patricia Hemenway 4.0 .7 4 17
eastern EA TB Savage 4.4 .84 5 20
northeast NE AM Main Jr. 5.1 .94 3 13
western WE Sharon Gray 5.3 .97 5 23
north NO Margot Weber 4.5 .89 5 9
central CT Ann Stephens 5.7 .94 5 13
northeast NE AM Main Jr. 5.1 .94 3 13
You have new mail in /var/spool/mail/root
[root@teacher test]# sed -e '/^north/H' -e '$G' datafile
northwest NW Charles Main 3.0 .98 3 34
western WE Sharon Gray 5.3 .97 5 23
southwest SW Lewis Dalsass 2.7 .8 2 18
southern SO Suan Chin 5.1 .95 4 15
southeast SE Patricia Hemenway 4.0 .7 4 17
eastern EA TB Savage 4.4 .84 5 20
northeast NE AM Main Jr. 5.1 .94 3 13
western WE Sharon Gray 5.3 .97 5 23
north NO Margot Weber 4.5 .89 5 9
central CT Ann Stephens 5.7 .94 5 13
northwest NW Charles Main 3.0 .98 3 34
northeast NE AM Main Jr. 5.1 .94 3 13
north NO Margot Weber 4.5 .89 5 9
[root@teacher test]# sed -e '/^north/h' -e '$G' datafile
northwest NW Charles Main 3.0 .98 3 34
western WE Sharon Gray 5.3 .97 5 23
southwest SW Lewis Dalsass 2.7 .8 2 18
southern SO Suan Chin 5.1 .95 4 15
southeast SE Patricia Hemenway 4.0 .7 4 17
eastern EA TB Savage 4.4 .84 5 20
northeast NE AM Main Jr. 5.1 .94 3 13
western WE Sharon Gray 5.3 .97 5 23
north NO Margot Weber 4.5 .89 5 9
central CT Ann Stephens 5.7 .94 5 13
north NO Margot Weber 4.5 .89 5
[root@teacher test]# sed -e '/WE/{h;d;}' -e '/CT/G' datafile
northwest NW Charles Main 3.0 .98 3 34
southwest SW Lewis Dalsass 2.7 .8 2 18
southern SO Suan Chin 5.1 .95 4 15
southeast SE Patricia Hemenway 4.0 .7 4 17
eastern EA TB Savage 4.4 .84 5 20
northeast NE AM Main Jr. 5.1 .94 3 13
north NO Margot Weber 4.5 .89 5 9
central CT Ann Stephens 5.7 .94 5 13
western WE Sharon Gray 5.3 .97 5
[root@teacher test]# sed -e '/WE/{h;d;}' -e '/CT/g' datafile
northwest NW Charles Main 3.0 .98 3 34
southwest SW Lewis Dalsass 2.7 .8 2 18
southern SO Suan Chin 5.1 .95 4 15
southeast SE Patricia Hemenway 4.0 .7 4 17
eastern EA TB Savage 4.4 .84 5 20
northeast NE AM Main Jr. 5.1 .94 3 13
north NO Margot Weber 4.5 .89 5 9
western WE Sharon Gray 5.3 .97 5
# sed -e '1h;2,3H' -e '5G' s3
----------------------------------
sedsed
# cd /test
# ./sedsed
ERROR: there's no SED script to parse! (try --help)
[root@teacher test]# ./sedsed --help
[root@teacher test]# cat a2
tom
mike
[root@teacher test]# ./sedsed -d '1h;2H;' a2
----------------------------------------
-i 修改源文件
[root@teacher test]# cp /etc/vsftpd/vsftpd.conf ./
练习：
把匿名用户禁止， 系统用户上传的文件权限为666，设置白名单。
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-f 调用sed脚本
12 #anonymous_enable=YES
22 local_umask=022
chroot_local_user is YES,
96 #chroot_list_enable=YES
97 # (default follows)
98 #chroot_list_file=/etc/vsftpd/chroot_list
# vim vsftp.s
s/#anonymous_enable=YES/anonymous_enable=NO/
s/local_umask=022/local_umask=000/
/chroot_local_user/a chroot_local_user=YES
s/#\(chroot_list_enable=YES\)/\1/
s/#chroot_list_file/chroot_list_file/
# sed -i -f vsftp.s vsftpd.conf
12 anonymous_enable=NO
22 local_umask=000
95 chroot_local_user=YES
97 chroot_list_enable=YES
99 chroot_list_file=/etc/vsftpd/chroot_list
