Sort Command in Linux with Examples
Sort Command
In this article we will cover about various Sort command used in Linux. It is used to print lines of input text files in sorted order.
To create a text file
Options
-e enables interpretation of backslash
/n tells echo to write each string to new line
[user1@linuxhelp Desktop]$ echo -e " centos
redhat
debian
linuxmint
arch
ubuntu
fedora
opensuse
mageia
manjaro" > os.txt
To look at the contents of file
[user1@linuxhelp Desktop]$ cat os.txt
centos
redhat
debian
linuxmint
arch
ubuntu
fedora
opensuse
mageia
manjaro
To sort contents of file
The following sort command is used to sort contents of file.
[user1@linuxhelp Desktop]$ sort os.txt
arch
centos
debian
fedora
linuxmint
mageia
manjaro
opensuse
redhat
ubuntu
It shows the sorted output of the file in the terminal.
To verify the Contents
Redirect the os.txt file to sorted.txt file. Now use cat command to verify the Contents of file.
[user1@linuxhelp Desktop]$ sort os.txt > sorted.txt
[user1@linuxhelp Desktop]$ cat sorted.txt
arch
centos
debian
fedora
linuxmint
mageia
manjaro
opensuse
redhat
ubuntu
To sort in reverse order
The following sort command is used to sort in reverse order. -r switch is used to redirect output of a file in reverse order.
[user1@linuxhelp Desktop]$ sort -r os.txt > rsorted.txt
[user1@linuxhelp Desktop]$ cat rsorted.txt
ubuntu
redhat
opensuse
manjaro
mageia
linuxmint
fedora
debian
centos
arch
To create new file in same location
To list
ls -l is used to list the output in the home directory.
[user1@linuxhelp Desktop]$ ls -l /home/user1/Documents/ > /home/user1/Desktop/new.txt
[user1@linuxhelp Desktop]$ cat new.txt
total 24
drwxrwxr-x 2 user1 user1 4096 Mar 9 15:52 dir5
drwxrwxr-x 2 user1 user1 4096 Mar 9 15:52 dir6
drwxrwxr-x 2 user1 user1 4096 Mar 9 15:52 dir7
-rw-rw-r-- 1 user1 user1 0 Mar 9 15:52 file1
-rw-rw-r-- 1 user1 user1 62 Mar 9 15:53 file2
-rw-rw-r-- 1 user1 user1 0 Mar 9 15:52 file3
-rw-rw-r-- 1 user1 user1 23 Mar 9 15:53 file4
drwxrwxr-x 2 user1 user1 4096 Mar 9 15:53 test
To sort contents of file ‘ new.txt‘ on the basis of 2nd column
The following sort command -k is used to sort a file on basis of the column.
Example
Based on 2nd column
[user1@linuxhelp Desktop]$ sort -nk2 new.txt
-rw-rw-r-- 1 user1 user1 0 Mar 9 15:52 file1
-rw-rw-r-- 1 user1 user1 0 Mar 9 15:52 file3
-rw-rw-r-- 1 user1 user1 23 Mar 9 15:53 file4
-rw-rw-r-- 1 user1 user1 62 Mar 9 15:53 file2
drwxrwxr-x 2 user1 user1 4096 Mar 9 15:52 dir5
drwxrwxr-x 2 user1 user1 4096 Mar 9 15:52 dir6
drwxrwxr-x 2 user1 user1 4096 Mar 9 15:52 dir7
drwxrwxr-x 2 user1 user1 4096 Mar 9 15:53 test
total 24
-n option is used to specify the integers in the specified column.
Based on 9th column
[user1@linuxhelp Desktop]$ sort -k9 new.txt
total 24
drwxrwxr-x 2 user1 user1 4096 Mar 9 15:52 dir5
drwxrwxr-x 2 user1 user1 4096 Mar 9 15:52 dir6
drwxrwxr-x 2 user1 user1 4096 Mar 9 15:52 dir7
-rw-rw-r-- 1 user1 user1 0 Mar 9 15:52 file1
-rw-rw-r-- 1 user1 user1 62 Mar 9 15:53 file2
-rw-rw-r-- 1 user1 user1 0 Mar 9 15:52 file3
-rw-rw-r-- 1 user1 user1 23 Mar 9 15:53 file4
drwxrwxr-x 2 user1 user1 4096 Mar 9 15:53 test
To pipeline it directly on the terminal with actual command
To list the contents in the documents folder directly in sorted order follow the below command.
[user1@linuxhelp Desktop]$ ls -l /home/user1/Documents | sort -nk5
-rw-rw-r-- 1 user1 user1 0 Mar 9 15:52 file1
-rw-rw-r-- 1 user1 user1 0 Mar 9 15:52 file3
total 24
-rw-rw-r-- 1 user1 user1 23 Mar 9 15:53 file4
-rw-rw-r-- 1 user1 user1 62 Mar 9 15:53 file2
drwxrwxr-x 2 user1 user1 4096 Mar 9 15:52 dir5
drwxrwxr-x 2 user1 user1 4096 Mar 9 15:52 dir6
drwxrwxr-x 2 user1 user1 4096 Mar 9 15:52 dir7
drwxrwxr-x 2 user1 user1 4096 Mar 9 15:53 test
To sort and remove duplicates
In os.txt file " arch" is repeated twice using -u option we can remove the duplicate one.
[user1@linuxhelp Desktop]$ cat os.txt centos arch redhat debian linuxmint arch ubuntu fedora opensuse mageia manjaro redhat [user1@linuxhelp Desktop]$ sort -u os.txt arch centos debian fedora linuxmint mageia manjaro opensuse redhat ubuntu
To sort contents of two files in single output
To sort and display the contents of os.txt file and new.txt file in single output.
[user1@linuxhelp Desktop]$ sort os.txt new.txt
arch
arch
centos
debian
drwxrwxr-x 2 user1 user1 4096 Mar 9 15:52 dir5
drwxrwxr-x 2 user1 user1 4096 Mar 9 15:52 dir6
drwxrwxr-x 2 user1 user1 4096 Mar 9 15:52 dir7
drwxrwxr-x 2 user1 user1 4096 Mar 9 15:53 test
fedora
linuxmint
mageia
manjaro
opensuse
redhat
-rw-rw-r-- 1 user1 user1 0 Mar 9 15:52 file1
-rw-rw-r-- 1 user1 user1 0 Mar 9 15:52 file3
-rw-rw-r-- 1 user1 user1 23 Mar 9 15:53 file4
-rw-rw-r-- 1 user1 user1 62 Mar 9 15:53 file2
total 24
ubuntu
To sort, merge and display the contents of os.txt file and new.txt file in single output.
[user1@linuxhelp Desktop]$ sort -u os.txt new.txt
arch
centos
debian
drwxrwxr-x 2 user1 user1 4096 Mar 9 15:52 dir5
drwxrwxr-x 2 user1 user1 4096 Mar 9 15:52 dir6
drwxrwxr-x 2 user1 user1 4096 Mar 9 15:52 dir7
drwxrwxr-x 2 user1 user1 4096 Mar 9 15:53 test
fedora
linuxmint
mageia
manjaro
opensuse
redhat
-rw-rw-r-- 1 user1 user1 0 Mar 9 15:52 file1
-rw-rw-r-- 1 user1 user1 0 Mar 9 15:52 file3
-rw-rw-r-- 1 user1 user1 23 Mar 9 15:53 file4
-rw-rw-r-- 1 user1 user1 62 Mar 9 15:53 file2
total 24
ubuntu
To create a text file ' month.txt'
[user1@linuxhelp Desktop]$ echo -e " march
april
july
june
jan
oct" > month.txt
[user1@linuxhelp Desktop]$ cat month.txt
march
april
july
june
jan
oct
To sort the file ‘ month.txt‘ on the basis of month order
Use switch -M to sort the file ‘ month.txt‘ on the basis of month order -month-sort
[user1@linuxhelp Desktop]$ sort -M month.txt
jan
march
april
june
july
oct
To check if files are sorted or not using sort command
Using -c option you can check if the file is sorted or not. If it is sorted it won’ t display any output
[user1@linuxhelp Desktop]$ sort -c sorted.txt
Or else it will display the disordered line number.
[user1@linuxhelp Desktop]$ sort -c os.txt
sort: os.txt:2: disorder: arch
To Sort on the basis of column
For contents separated by anything other than space like ‘ |’ or ‘ ’ or ‘ +’ or ‘ .’
[user1@linuxhelp Desktop]$ echo -e " 34+windows+linux+unix
45+mageia+opensuse+redhat
546+mongodb+tomcat+perl
5+python+java+php
368+zimbra+lotus+gmail" > linux.txt
[user1@linuxhelp Desktop]$ cat linux.txt
34+windows+linux+unix
45+mageia+opensuse+redhat
546+mongodb+tomcat+perl
5+python+java+php
368+zimbra+lotus+gmail
To sort file on the basis of 1st field
The following sort command is used to sort file on the basis of 1st field.
[user1@linuxhelp Desktop]$ sort -t ' +' -nk1 linux.txt
5+python+java+php
34+windows+linux+unix
45+mageia+opensuse+redhat
368+zimbra+lotus+gmail
546+mongodb+tomcat+perl
[user1@linuxhelp Desktop]$ sort -t ' +' -k4 linux.txt
368+zimbra+lotus+gmail
546+mongodb+tomcat+perl
5+python+java+php
45+mageia+opensuse+redhat
34+windows+linux+unix
To sort the contents of ' ls -l' command for your home directory
On basis of 5th column
It returns the values based on the amount of data in random order.
[user1@linuxhelp Desktop]$ ls -l /home/user1/Documents/ | sort -k5 -R
drwxrwxr-x 2 user1 user1 4096 Mar 9 15:52 dir5
total 24
-rw-rw-r-- 1 user1 user1 62 Mar 9 15:53 file2
-rw-rw-r-- 1 user1 user1 0 Mar 9 15:52 file1
drwxrwxr-x 2 user1 user1 4096 Mar 9 15:52 dir6
drwxrwxr-x 2 user1 user1 4096 Mar 9 15:53 test
-rw-rw-r-- 1 user1 user1 0 Mar 9 15:52 file3
-rw-rw-r-- 1 user1 user1 23 Mar 9 15:53 file4
drwxrwxr-x 2 user1 user1 4096 Mar 9 15:52 dir7
Whereas if you run the same command next time it won’ t return the same output
[user1@linuxhelp Desktop]$ ls -l /home/user1/Documents/ | sort -k5 -R
-rw-rw-r-- 1 user1 user1 62 Mar 9 15:53 file2
-rw-rw-r-- 1 user1 user1 0 Mar 9 15:52 file3
total 24
-rw-rw-r-- 1 user1 user1 0 Mar 9 15:52 file1
drwxrwxr-x 2 user1 user1 4096 Mar 9 15:52 dir5
-rw-rw-r-- 1 user1 user1 23 Mar 9 15:53 file4
drwxrwxr-x 2 user1 user1 4096 Mar 9 15:52 dir7
drwxrwxr-x 2 user1 user1 4096 Mar 9 15:53 test
drwxrwxr-x 2 user1 user1 4096 Mar 9 15:52 dir6
To override the default sorting preference
Before the override option is to be used we have to export the environment variable.
[user1@linuxhelp Desktop]$ export LC_ALL=C
[user1@linuxhelp Desktop]$ sort os.txt
Redhat
arch
centos
debian
fedora
linuxmint
mageia
manjaro
opensuse
ubuntu
Here, it overrides the uppercase letter as the first one.
Use option ‘ -f‘ aka ‘ &ndash ignore-case‘ to get organized output.
[user1@linuxhelp Desktop]$ sort -f os.txt
arch
centos
debian
fedora
linuxmint
mageia
manjaro
opensuse
Redhat
ubuntu
So it just sort and won’ t consider the lower and uppercase letters.
To run sort on two input file and merge
The following sort command is used to Create two text files and add some data and use cat command to check contents of the file.
[user1@linuxhelp Desktop]$ echo -e “ 1 redhat 3 centos 2 fedora” > file1.txt [user1@linuxhelp Desktop]$ cat file1.txt 1 redhat 3 centos 2 fedora
Add 2nd file with some data
[user1@linuxhelp Desktop]$ echo -e “ 3 debian 2 mageia 1 ubuntu” > file2.txt [user1@linuxhelp Desktop]$ cat file2.txt 3 debian 2 mageia 1 ubuntu
To merge output of both files
[user1@linuxhelp Desktop]$ join < (sort file1.txt) < (sort file2.txt)
1 redhat ubuntu
2 fedora mageia
3 centos debian