How to Use Sort Command in Linux: Syntax and Examples

Use the sort command in Linux to arrange lines of text alphabetically or numerically. The basic syntax is sort [options] filename, which outputs sorted lines to the terminal or a file.

Syntax

The basic syntax of the sort command is:

• sort [options] [file]

Here, file is the name of the text file to sort. If no file is given, sort reads from standard input.

Common options include:

• -r: reverse the sort order
• -n: sort numerically
• -k: sort by a specific column
• -o: write output to a file

bash

sort [options] [file]

Example

This example sorts a file named names.txt alphabetically and outputs the result:

bash

cat > names.txt <<EOF
Charlie
Alice
Bob
EOF

sort names.txt

Output

Alice
Bob
Charlie

Common Pitfalls

One common mistake is forgetting that sort outputs to the terminal by default and does not change the original file. Use -o filename to save sorted output back to a file.

Another pitfall is sorting numbers as text, which leads to incorrect order. Use -n to sort numerically.

bash

echo -e "10\n2\n1" > numbers.txt
sort numbers.txt
sort -n numbers.txt

Output

10
1
2
1
2
10

Quick Reference

Option	Description
-r	Sort in reverse order
-n	Sort numerically
-k	Sort by specific column (e.g., -k2)
-o	Write output to a file
-u	Output only unique lines

Key Takeaways

Use sort filename to sort lines alphabetically by default.

Add -n to sort numbers correctly instead of as text.

Use -r to reverse the sort order.

Use -o outputfile to save sorted results to a file.

Remember sort outputs to terminal unless redirected.