🐚 Shell Scripting Exercises (Beginner → Advanced)

A progressive set of exercises to help you master shell scripting step by step.

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🟢 Beginner Level (Basics)

Focus: commands, variables, simple scripts

1. Hello Script

• Write a script that prints:

  • “Hello, World!”
  • Your username
  • Current date

2. Variables Practice

• Ask the user for their name and age
• Print: “You will be X years old in 5 years”

3. File Check

• Ask for a filename

• Check:

  • If it exists
  • If it’s readable
  • If it’s writable

4. Simple Calculator

• Take two numbers as arguments

• Output:

  • Sum
  • Difference
  • Product

5. Loop Practice

• Print numbers from 1 to 20
• Then print only even numbers

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🟡 Intermediate Level (Logic & Automation)

Focus: conditionals, loops, functions

6. Backup Script

• Copy all .txt files from one folder to another
• Add a timestamp to the backup folder name

7. Log Analyzer

• Given a log file:

  • Count number of lines
  • Count occurrences of the word “ERROR”

8. User Menu Script

Create a menu:

1. Show current directory
2. List files
3. Show disk usage
4. Exit

• Keep looping until user exits

9. Function Practice

• Write functions:

  • is_even
  • factorial

• Call them from the script

10. File Organizer

• Move files into folders based on extension:

  • .jpg → images/
  • .txt → text/
  • .sh → scripts/

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🔵 Upper-Intermediate (Real-world Tasks)

Focus: pipes, awk/sed, process handling

11. Process Monitor

• Show top 5 processes by CPU usage
• Refresh every 5 seconds

12. Disk Usage Reporter

• Show directories larger than a given size
• Sort them by size

13. Bulk Rename Tool

• Rename files:

  • Replace spaces with underscores
  • Add prefix or suffix

14. CSV Parser

• Given a CSV file:

  • Print a specific column
  • Filter rows based on a condition

15. Simple Deployment Script

• Pull latest code from a Git repo
• Restart a service
• Log the deployment

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🔴 Advanced Level (Scripting Mastery)

Focus: robustness, system tools, automation

16. Argument Parser

• Support flags like:

  • -f <file>
  • -v (verbose)

• Use getopts

17. Parallel Execution Script

• Run multiple commands in parallel
• Wait for all to finish
• Collect exit statuses

18. System Health Check Tool

• Report:

  • CPU usage
  • Memory usage
  • Disk usage

• Output a nicely formatted report

19. Cron Job Manager

• Script to:

  • Add cron jobs
  • List cron jobs
  • Remove cron jobs

20. Interactive CLI Tool

• Build a full CLI utility with:

  • Help menu (--help)
  • Subcommands
  • Error handling

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⚫ Expert Challenges (Optional but Powerful)

21. Build Your Own grep

• Search for a pattern in a file

• Support flags like:

  • Case insensitive
  • Line numbers

22. Mini Shell

• Implement a basic shell:

  • Read command input
  • Execute commands
  • Handle cd, exit

23. Log Rotation System

• Archive logs when they exceed a size
• Compress old logs
• Keep only the last N logs

24. API Data Fetcher

• Use curl to fetch data from an API
• Parse JSON (using jq)
• Display formatted output

25. Automated Backup System

• Incremental backups
• Compression
• Remote sync (e.g., rsync)

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💡 Tips

• Try solving exercises without looking up solutions first

• Practice using:

  • grep, awk, sed
  • cron, systemctl, ps

• Add error handling:

  • set -e
  • trap

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Happy scripting! 🚀