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In this article, I will take you through 60 popular examples of sed command in Linux Part – 1. Sed is also known as Stream Editor and it can perform multiple operations on a file like searching, insertion and deletion. You will always see frequent use of sed and awk tool in Bash Scripting.
To know more about AWK Command, Check 60 Popular Examples of AWK Command in Linux Part – 1
Sed Command Examples
Also Read: How to Print Array in Bash Shell Script
1. Check Sed Command Version
If you want to check the Sed command version, then you need to use --version option with sed command in Linux as shown below. As you can check from the output, current installed version of sed is 4.2.2.
[root@localhost ~]# sed --version sed (GNU sed) 4.2.2 Copyright (C) 2012 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.
2. Print 1st Line of /etc/passwd
If you want to print only the 1st Line of /etc/passwd file, then you need to use 1p with -n option as shown in below sed command.
[root@localhost ~]# sed -n 1p /etc/passwd root:x:0:0:root:/root:/bin/bash
-n: Suppress automatic printing of pattern space
p: Print the current pattern space.
3. Print 6th Line of /etc/passwd
If you want to print only the 6th Line of /etc/passwd file, then you need to use 6p with -n option as shown below.
[root@localhost ~]# sed -n 6p /etc/passwd sync:x:5:0:sync:/sbin:/bin/sync
4. Print Line 1 to Line 6 of /etc/passwd
If you want to print Line 1 to Line 6 of /etc/passwd, then you need to use 1,6p with -n option as shown below.
[root@localhost ~]# sed -n '1,6p' /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
5. Print Line 1 and Line 6 only of /etc/passwd
If you want to print only Line 1 and Line 6 of /etc/passwd file, then you need to use 1p and 6p with -e option as shown below.
[root@localhost ~]# sed -n -e 1p -e 6p /etc/passwd root:x:0:0:root:/root:/bin/bash sync:x:5:0:sync:/sbin:/bin/sync
-e: add the script to the commands to be executed.
6. Print Last Line of /etc/passwd
Sometimes often the case that you don’t know how big the file is and what is the last line number of a file. In those scenarios, using this sed command would be very much helpful where you can print the last line of a file without using the line number.
[root@localhost ~]# sed -n '$p' /etc/passwd zookeeper:x:1000:1000::/home/zookeeper:/bin/bash
7. Print Last 2 Lines of /etc/passwd
If you want to print last two lines of /etc/passwd, then you need to use $!N;$!D with sed command as shown below.
[root@localhost ~]# sed '$!N;$!D' /etc/passwd opscode-pgsql:x:995:992::/var/opt/opscode/postgresql:/bin/sh zookeeper:x:1000:1000::/home/zookeeper:/bin/bash
N: Read/append the next line of input into the pattern space.
D: If pattern space contains no newline, start a normal new cycle as if the d command was issued. Otherwise, delete text in the pattern space up to the first newline, and restart cycle with the resultant pattern space, without reading a new line of input. For more information, visit Sed Man Page.
8. Print Every Alternate Line of /etc/passwd
If you want to print every alternate line of /etc/passwd file, then you need to use n;d with sed command as shown below.
[root@localhost ~]# sed 'n;d' /etc/passwd root:x:0:0:root:/root:/bin/bash daemon:x:2:2:daemon:/sbin:/sbin/nologin lp:x:4:7:lp:/var/spool/lpd:/sbin/nologin shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown mail:x:8:12:mail:/var/spool/mail:/sbin/nologin games:x:12:100:games:/usr/games:/sbin/nologin
n: Read/append the next line of input into the pattern space.
d: Delete pattern space. Start next cycle.
9. Print all Lines which contains ‘root’ keyword
If you want to print all the lines of /etc/passwd which contains keyword root, then you need to match the root keyword as shown below. Here, you can see three lines from /etc/passwd file which contains root keyword.
[root@localhost ~]# sed -n '/root/p' /etc/passwd root:x:0:0:root:/root:/bin/bash operator:x:11:0:operator:/root:/sbin/nologin dockerroot:x:997:994:Docker User:/var/lib/docker:/sbin/nologin
10. Print all Lines which does not contain ‘root’ keyword
If you want to print all Lines that does not contain root keyword, then you need to use exclamation(!) with p as shown below. As you can see from below output, there are multiple lines which does not have root keyword.
[root@localhost ~]# sed -n '/root/!p' /etc/passwd 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
11. Print all Lines which starts with ‘root’ Keyword
If you want to print only those lines which starts with root keyword, then you can use ^ operator in the matching pattern as shown below. As you can see, there is only one line which contains root keyword in the beginning.
[root@localhost ~]# sed -n '/^root/p' /etc/passwd root:x:0:0:root:/root:/bin/bash
12. Print all Lines which does not start with ‘root’ Keyword
If you want to print only those lines which does not start with root keyword, then you need to use exclamation mark(!) with print(p) as shown below.
[root@localhost ~]# sed -n '/^root/!p' /etc/passwd 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
13. Print all Lines which ends with ‘bash’ Keyword
If you want to print only those lines which ends with bash keyword, then you need to use $ operator at the end of bash keyword in the matching pattern as shown below. As you can see from the output, there are only two such lines which has bash keyword at the end of that line.
[root@localhost ~]# sed -n '/bash$/p' /etc/passwd root:x:0:0:root:/root:/bin/bash zookeeper:x:1000:1000::/home/zookeeper:/bin/bash
14. Print all Lines which does not end with ‘bash’ Keyword
If you want to print only those lines which does not end with bash keyword, then you need to use exclamation mark(!) with print(p) as shown below. You can see from below output that there are multiple lines in /etc/passwd file which does not end with bash keyword.
[root@localhost ~]# sed -n '/bash$/!p' /etc/passwd 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
15. Print all Lines which contain either ‘root’ or ‘bash’ keyword in /etc/passwd
If you want to print only those lines which contains either root or bash keyword, then you need to use /root\|bash/ in the matching pattern as shown below.
[root@localhost ~]# sed -n '/root\|bash/p' /etc/passwd root:x:0:0:root:/root:/bin/bash operator:x:11:0:operator:/root:/sbin/nologin dockerroot:x:997:994:Docker User:/var/lib/docker:/sbin/nologin zookeeper:x:1000:1000::/home/zookeeper:/bin/bash
16. Print all Lines which does not contain either ‘root’ or ‘bash’ keyword in /etc/passwd
If you want to print only those lines which does not contain either root or bash keyword, then you need to use exclamation mark(!) with print(p) as shown below.
[root@localhost ~]# sed -n '/root\|bash/!p' /etc/passwd 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
17. Print all Lines which contains digit ‘4’ or ‘5’
If you want to print only those lines which contains digit 4 or 5, then you need to use range /4-5/ in matching pattern as shown below.
[root@localhost ~]# sed -n '/[4-5]/p' /etc/passwd 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 ftp:x:14:50:FTP User:/var/ftp:/sbin/nologin sshd:x:74:74:Privilege-separated SSH:/var/empty/sshd:/sbin/nologin dockerroot:x:997:994:Docker User:/var/lib/docker:/sbin/nologin opscode-pgsql:x:995:992::/var/opt/opscode/postgresql:/bin/sh
18. Print all Lines which does not contain digit ‘4’ or ‘5’
If you want to print only those lines which does not contain digit 4 or 5, then you need to use exclamation mark(!) with print(p) as shown below.
[root@localhost ~]# sed -n '/[4-5]/!p' /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 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 nobody:x:99:99:Nobody:/:/sbin/nologin systemd-network:x:192:192:systemd Network Management:/:/sbin/nologin
19. Print all Lines which contains character ‘y’ or ‘z’
If you want to print only those lines from /etc/passwd file which contains character y or z, then you can use /[y-z]/ in the matching pattern as shown below.
[root@localhost ~]# sed -n '/[y-z]/p' /etc/passwd sync:x:5:0:sync:/sbin:/bin/sync nobody:x:99:99:Nobody:/:/sbin/nologin systemd-network:x:192:192:systemd Network Management:/:/sbin/nologin dbus:x:81:81:System message bus:/:/sbin/nologin sshd:x:74:74:Privilege-separated SSH:/var/empty/sshd:/sbin/nologin chrony:x:998:996::/var/lib/chrony:/sbin/nologin zookeeper:x:1000:1000::/home/zookeeper:/bin/bash
20. Print all Lines which does not contains character ‘y’ or ‘z’
If you want to print all the lines from /etc/passwd file which does not contains character y and z, then you need to use exclamation mark(!) with p to achieve that as shown below.
[root@localhost ~]# sed -n '/[y-z]/!p' /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 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
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