head and tail in Linux CLI - Mini Project: Build & Apply

Using head and tail Commands in Linux CLI

📖 Scenario: You are working with a text file that contains a list of daily sales records for a small shop. You want to quickly check the first few and last few lines of this file to understand the data without opening the entire file.

🎯 Goal: Learn how to use the head and tail commands to view the beginning and end of a text file in the Linux command line.

📋 What You'll Learn

Create a text file named sales.txt with specific lines

Use head command to view the first 3 lines

Use tail command to view the last 2 lines

Print the outputs of both commands

💡 Why This Matters

🌍 Real World

Checking the start and end of log files or data files quickly without opening the entire file saves time and helps find important information fast.

💼 Career

System administrators, developers, and data analysts often use head and tail commands to inspect files and troubleshoot issues efficiently.

1

Create the sales.txt file

Create a file named sales.txt with these exact lines, each on its own line:
Monday: 150
Tuesday: 200
Wednesday: 180
Thursday: 220
Friday: 170

Linux CLI

# Create the sales.txt file with the specified lines
# Your code here

Need a hint?

Use echo -e with newline characters \n and redirect output to sales.txt.

2

Set the number of lines to view

Create two variables: head_lines set to 3 and tail_lines set to 2 to specify how many lines to view from the start and end of the file.

Linux CLI

echo -e "Monday: 150\nTuesday: 200\nWednesday: 180\nThursday: 220\nFriday: 170" > sales.txt
# Set head_lines to 3 and tail_lines to 2
# Your code here

Need a hint?

Use simple variable assignment like head_lines=3.

3

Use head and tail commands with variables

Use the head command with -n option and the variable head_lines to show the first 3 lines of sales.txt. Then use the tail command with -n and tail_lines to show the last 2 lines.

Linux CLI

echo -e "Monday: 150\nTuesday: 200\nWednesday: 180\nThursday: 220\nFriday: 170" > sales.txt
head_lines=3
tail_lines=2
# Use head and tail commands with the variables
# Your code here

Need a hint?

Use head -n $head_lines sales.txt and tail -n $tail_lines sales.txt.

4

Print the outputs of head and tail

Print the output of the head command first, then print a blank line, then print the output of the tail command. Use the variables head_lines and tail_lines in the commands.

Linux CLI

echo -e "Monday: 150\nTuesday: 200\nWednesday: 180\nThursday: 220\nFriday: 170" > sales.txt
head_lines=3
tail_lines=2
# Print head output, then a blank line, then tail output
# Your code here

Need a hint?

Use an empty echo between the two commands to separate outputs.