diff for file comparison in Linux CLI - Mini Project: Build & Apply

Compare Two Text Files Using diff

📖 Scenario: You work as a system administrator. You often need to check if two configuration files are the same or if they have differences.Using the diff command helps you quickly find differences between two files.

🎯 Goal: Learn how to use the diff command to compare two text files and see their differences.

📋 What You'll Learn

Create two text files with specific content

Use the diff command to compare the two files

Understand the output of diff showing differences

💡 Why This Matters

🌍 Real World

System administrators and developers often need to check differences between configuration files or code versions to troubleshoot or review changes.

💼 Career

Knowing how to use diff is essential for tasks like code reviews, debugging, and managing system configurations.

1

Create the first file file1.txt

Create a file called file1.txt with these exact three lines:
apple
banana
cherry

Linux CLI

# Use a command to create file1.txt with the specified lines
# Your code here

Need a hint?

Use echo with -e to add new lines and redirect output to file1.txt.

2

Create the second file file2.txt

Create a file called file2.txt with these exact three lines:
apple
banana
date

Linux CLI

# Use a command to create file2.txt with the specified lines
# Your code here

Need a hint?

Use echo with -e and redirect output to file2.txt.

3

Use diff to compare the two files

Use the diff command with file1.txt and file2.txt to find differences between them.

Linux CLI

echo -e "apple\nbanana\ncherry" > file1.txt
echo -e "apple\nbanana\ndate" > file2.txt
# Use diff to compare file1.txt and file2.txt
# Your code here

Need a hint?

Simply run diff file1.txt file2.txt to see the differences.

4

View the output showing the difference

Run the script and observe the output. It should show the difference between file1.txt and file2.txt indicating that cherry was replaced by date.

Linux CLI

echo -e "apple\nbanana\ncherry" > file1.txt
echo -e "apple\nbanana\ndate" > file2.txt
diff file1.txt file2.txt
# Observe the output below
# Your code here

Need a hint?

The output shows line 3 changed from cherry to date.