Linux sort Command

The Linux sort command is used to sort the contents of a text file.

sort can sort the contents of a text file line by line.

sort [-bcdfimMnr][-o&lt;output file>][-t<delimiter>][+&lt;start field>-&lt;end field>][--help][--version][file][-k field1[,field2]]

Parameter Description:

-b Ignore leading blank spaces in each line.
-c Check if the file is already sorted in order.
-d Sort, considering only letters, numbers, and spaces, ignoring other characters.
-f Treat lowercase letters as uppercase during sorting.
-i Ignore characters outside the ASCII range 040 to 176 during sorting.
-m Merge several sorted files.
-M Sort by the first three letters as month abbreviations.
-n Sort by numerical value.
-u Ensures uniqueness, outputting the result after removing duplicates.
-o<output file> Save the sorted result to the specified file.
-r Sort in reverse order.
-t<delimiter> Specify the field delimiter for sorting.
+<start field>-<end field> Sort by the specified fields, ranging from the start field to the field before the end field.
--help Display help.
--version Display version information.
[-k field1[,field2]] Sort by the specified columns.

To sort the lines of a file using the default method with the sort command, use the following command:

sort testfile

The sort command will sort the first column of the text file in ASCII order by default and output the result to the standard output.

Using the cat command to display the testfile file shows the original order as follows:

$ cat testfile      # Original order of testfile  
test 30  
Hello 95  
Linux 85

The result after using the sort command is as follows:

$ sort testfile # Rearranged result  
Hello 95  
Linux 85  
test 30

Using the -k parameter to sort by the second column, the result is as follows:

$ sort testfile -k 2
test 30  
Linux 85 
Hello 95