grep (search text patterns) in Linux CLI - Mini Project: Build & Apply

Using grep to Search Text Patterns

📖 Scenario: You are working with a simple text file that contains a list of fruits and their colors. You want to find specific fruits by searching for text patterns inside this file.

🎯 Goal: Learn how to use the grep command to search for text patterns in a file and display matching lines.

📋 What You'll Learn

Create a text file named fruits.txt with exact content

Use a variable to store the search pattern

Use grep with the variable to find matching lines

Display the matching lines as output

💡 Why This Matters

🌍 Real World

Searching text files for specific words or patterns is common when working with logs, configuration files, or data files.

💼 Career

Knowing how to use grep helps in troubleshooting, data analysis, and automating tasks in many IT and software roles.

1

Create the text file fruits.txt

Create a file named fruits.txt with these exact lines:
apple red
banana yellow
cherry red
grape purple
lemon yellow

Linux CLI

# Create the file fruits.txt with the exact lines
# Your code here

Need a hint?

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

2

Set a variable for the search pattern

Create a variable called pattern and set it to the exact string red.

Linux CLI

echo -e "apple red\nbanana yellow\ncherry red\ngrape purple\nlemon yellow" > fruits.txt
# Set the variable pattern to 'red'
# Your code here

Need a hint?

Use pattern=red to assign the string.

3

Use grep with the variable to find matching lines

Use the grep command with the variable $pattern to search inside fruits.txt and show matching lines.

Linux CLI

echo -e "apple red\nbanana yellow\ncherry red\ngrape purple\nlemon yellow" > fruits.txt
pattern=red
# Use grep with $pattern to search fruits.txt
# Your code here

Need a hint?

Use grep "$pattern" fruits.txt to search using the variable.

4

Display the matching lines

Run the script to display all lines from fruits.txt that contain the word red.

Linux CLI

echo -e "apple red\nbanana yellow\ncherry red\ngrape purple\nlemon yellow" > fruits.txt
pattern=red
grep "$pattern" fruits.txt
# Run the command to show output

Need a hint?

The output should show only lines containing 'red'.