Cheat Sheet #day59 - diff

diff Command Cheatsheet

The diff command in Unix-like systems is used to compare two files line by line and display the differences between them. Here’s a quick reference guide:

Basic Syntax

diff [OPTION]... FILE1 FILE2

Common Options

• -u, --unified: Show differences in a unified format. This is the most commonly used format.

    diff -u file1.txt file2.txt
  

• -c, --context: Show differences in a context format, which includes a few lines of context before and after each change.

    diff -c file1.txt file2.txt
  

• -i, --ignore-case: Ignore case differences.

    diff -i file1.txt file2.txt
  

• -w, --ignore-all-space: Ignore all white space.

    diff -w file1.txt file2.txt
  

• -B, --ignore-blank-lines: Ignore changes whose lines are all blank.

    diff -B file1.txt file2.txt
  

• -y: Display differences side by side.

    diff -y file1.txt file2.txt
  

• -Z, --ignore-trailing-space: Ignore whitespace at the end of lines.

    diff -Z file1.txt file2.txt
  

Examples

1. Basic difference between two files:

    diff file1.txt file2.txt
   

2. Unified format comparison:

    diff -u file1.txt file2.txt
   

3. Context format comparison:

    diff -c file1.txt file2.txt
   

4. Ignore case differences:

    diff -i file1.txt file2.txt
   

5. Ignore all white space:

    diff -w file1.txt file2.txt
   

6. Ignore blank lines:

    diff -B file1.txt file2.txt
   

7. Side-by-side comparison:

    diff -y file1.txt file2.txt
   

8. Ignore trailing spaces:

    diff -Z file1.txt file2.txt
   

Displaying Differences with Line Numbers

• Show line numbers in the output:

    diff -n file1.txt file2.txt
  

Additional Information

• Help option:

    diff --help
  

• View diff manual page:

    man diff
  

This cheatsheet covers the essential options and usage scenarios for the diff command. For more advanced features and details, refer to the man page or use diff --help.