Bash & PowerShell Scripting Part-2

Script #1

Hello World Beginner

📝 Display a simple message to the screen

🎯

What You’ll Learn Basic output, running scripts

⏱️

Estimated Time 5 minutes

🔧

Tools Needed Terminal/PowerShell, text editor

🎓 Concepts Covered

How to create a script file
Basic output commands
Running your first script
Understanding script syntax

📋 Step-by-Step Instructions

Create a new file

Bash: Create a file called hello.sh

PowerShell: Create a file called hello.ps1

Use any text editor like Notepad, nano, vim, or VS Code.

Write the code

Type the script code shown below. The echo command (Bash) or Write-Host (PowerShell) displays text on the screen.

Save the file

Save your script in a location you can easily find, like your home directory or Desktop.

Make it executable (Bash only)

In terminal, run: chmod +x hello.sh

This gives the script permission to run.

Run the script

Bash: ./hello.sh

PowerShell: .\hello.ps1

💻 Complete Code

Bash (hello.sh)

#!/bin/bash
# My first Bash script

echo "Hello, World!"
echo "Welcome to scripting!"

PowerShell (hello.ps1)

# My first PowerShell script

Write-Host "Hello, World!"
Write-Host "Welcome to scripting!"

▶️ Sample Output

Expected output:

Hello, World! Welcome to scripting!

🎨 3 Ways to Customize

Add more messages: Add additional echo or Write-Host lines with different text
Use colors (PowerShell): Try Write-Host “Hello!” -ForegroundColor Green

Add ASCII art: Display fun text art like:

  _   _      _ _       
 | | | | ___| | | ___  
 | |_| |/ _ \ | |/ _ \ 
 |  _  |  __/ | | (_) |
 |_| |_|\___|_|_|\___/

⚠️ Common Mistakes

Forgetting the shebang (Bash): The #!/bin/bash line tells the system how to run the script
Wrong file extension: Use .sh for Bash and .ps1 for PowerShell
Not making executable (Bash): Must run chmod +x before running
Typos in commands: Commands must be spelled exactly right (case matters in Bash!)

✅ Success Criteria

You’ve succeeded if:

The script runs without errors
You see “Hello, World!” displayed on the screen
You can run the script multiple times

Script #2

Personal Greeting Beginner

📝 Greet yourself using variables to store your name

🎯

What You’ll Learn Variables, string manipulation

⏱️

Estimated Time 8 minutes

🔧

Tools Needed Terminal/PowerShell, text editor

🎓 Concepts Covered

Creating and using variables
Storing text (strings) in variables
Combining variables with text
Variable naming conventions

📋 Step-by-Step Instructions

Understand variables

Variables are like labeled boxes that store information. You can put a value in the box and use it later.

Bash syntax: name=”value” (no spaces around =)

PowerShell syntax: $name = “value” (spaces OK)

Create variables for personal info

Store your name, age, and city in separate variables.

Display the greeting

Use the variables in your echo/Write-Host statements. In Bash, use $variable to access the value. PowerShell is the same!

Run and test

Execute your script and verify it displays your personal information correctly.

💻 Complete Code

Bash (greeting.sh)

#!/bin/bash
# Personal greeting with variables

name="Sarah"
age=25
city="Portland"

echo "=============================="
echo "     PERSONAL PROFILE"
echo "=============================="
echo ""
echo "Name: $name"
echo "Age: $age years old"
echo "City: $city"
echo ""
echo "Hello, $name! Welcome to scripting from $city!"

PowerShell (greeting.ps1)

# Personal greeting with variables

$name = "Sarah"
$age = 25
$city = "Portland"

Write-Host "==============================" -ForegroundColor Cyan
Write-Host "     PERSONAL PROFILE" -ForegroundColor Cyan
Write-Host "==============================" -ForegroundColor Cyan
Write-Host ""
Write-Host "Name: $name"
Write-Host "Age: $age years old"
Write-Host "City: $city"
Write-Host ""
Write-Host "Hello, $name! Welcome to scripting from $city!" -ForegroundColor Green

▶️ Sample Output

Expected output:

============================== PERSONAL PROFILE ============================== Name: Sarah Age: 25 years old City: Portland Hello, Sarah! Welcome to scripting from Portland!

🎨 3 Ways to Customize

Add more fields: Include favorite color, hobby, or occupation
Calculate birth year: Add birth_year=$((2025 – age)) and display it
Create a bio paragraph: Combine all variables into one personalized story

⚠️ Common Mistakes

Spaces around = (Bash): name = “Sarah” won’t work—must be name=”Sarah”
Forgetting $ when using variable: echo name prints “name” literally, not the value
Quotes matter: Use quotes for text values to avoid issues with spaces
Case sensitivity (Bash): $Name and $name are different variables!

✅ Success Criteria

You’ve succeeded if:

Your script displays all three pieces of information
Variables are correctly inserted into sentences
You can change variable values and see updated output

Script #3

Interactive Echo Beginner

📝 Ask the user for input and echo it back

🎯

What You’ll Learn User input, interactive scripts

⏱️

Estimated Time 10 minutes

🔧

Tools Needed Terminal/PowerShell

🎓 Concepts Covered

Reading user input
Storing input in variables
Making scripts interactive
Prompting users effectively

📋 Step-by-Step Instructions

Learn the input commands

Bash: read variable_name waits for user input

PowerShell: Read-Host “prompt” asks and stores input

Ask multiple questions

Prompt the user for their name, favorite color, and a number. Store each response in a variable.

Echo back the responses

Display all the information the user provided in a friendly format.

💻 Complete Code

Bash (echo_input.sh)

#!/bin/bash
# Interactive input and echo

echo "===== Interactive Echo Program ====="
echo ""

echo "What is your name?"
read name

echo "What is your favorite color?"
read color

echo "Pick a number between 1 and 100:"
read number

echo ""
echo "===== Here's what you told me ====="
echo "Name: $name"
echo "Favorite Color: $color"
echo "Lucky Number: $number"
echo ""
echo "Nice to meet you, $name! $color is a great color!"

PowerShell (echo_input.ps1)

# Interactive input and echo

Write-Host "===== Interactive Echo Program =====" -ForegroundColor Cyan
Write-Host ""

$name = Read-Host "What is your name?"
$color = Read-Host "What is your favorite color?"
$number = Read-Host "Pick a number between 1 and 100"

Write-Host ""
Write-Host "===== Here's what you told me =====" -ForegroundColor Yellow
Write-Host "Name: $name"
Write-Host "Favorite Color: $color"
Write-Host "Lucky Number: $number"
Write-Host ""
Write-Host "Nice to meet you, $name! $color is a great color!" -ForegroundColor Green

▶️ Sample Output

Example interaction:

===== Interactive Echo Program ===== What is your name? John What is your favorite color? Blue Pick a number between 1 and 100: 42 ===== Here’s what you told me ===== Name: John Favorite Color: Blue Lucky Number: 42 Nice to meet you, John! Blue is a great color!

🎨 3 Ways to Customize

Add more questions: Ask about age, city, hobby, or favorite food
Do math with the number: Multiply their number by 2 and show the result
Hidden input (Bash): Use read -s password for secret input (like passwords)

⚠️ Common Mistakes

Not waiting for input: Make sure your script pauses for the user to type
Empty inputs: Users might press Enter without typing anything
Spelling variable names: If you store in $name, you must use $name (not $username)

✅ Success Criteria

You’ve succeeded if:

Script asks questions and waits for answers
All inputs are correctly echoed back
The conversation feels natural and friendly

Script #4

Simple Calculator Easy

📝 Perform basic math operations on user-provided numbers

🎯

What You’ll Learn Arithmetic operations, number handling

⏱️

Estimated Time 12 minutes

🔧

Tools Needed Terminal/PowerShell

🎓 Concepts Covered

Mathematical operations (+, -, *, /)
Working with numbers in scripts
Converting string input to numbers
Displaying calculated results

📋 Step-by-Step Instructions

Understand arithmetic syntax

Bash: Use $((expression)) for math, e.g., $((5 + 3))

PowerShell: Math works directly, but convert input with [int]$variable

Get two numbers from user

Prompt for two numbers and store them in variables.

Perform all operations

Calculate sum, difference, product, and quotient. Store each result in its own variable.

Display results

Show all calculated results in a clear, formatted way.

💻 Complete Code

Bash (calculator.sh)

#!/bin/bash
# Simple calculator

echo "====== Simple Calculator ======"
echo ""

read -p "Enter first number: " num1
read -p "Enter second number: " num2

# Perform calculations
sum=$((num1 + num2))
difference=$((num1 - num2))
product=$((num1 * num2))
quotient=$((num1 / num2))

# Display results
echo ""
echo "====== Results ======"
echo "$num1 + $num2 = $sum"
echo "$num1 - $num2 = $difference"
echo "$num1 × $num2 = $product"
echo "$num1 ÷ $num2 = $quotient"
echo ""
echo "Thanks for calculating!"

PowerShell (calculator.ps1)

# Simple calculator

Write-Host "====== Simple Calculator ======" -ForegroundColor Cyan
Write-Host ""

$num1 = Read-Host "Enter first number"
$num2 = Read-Host "Enter second number"

# Convert to integers and perform calculations
$num1 = [int]$num1
$num2 = [int]$num2

$sum = $num1 + $num2
$difference = $num1 - $num2
$product = $num1 * $num2
$quotient = $num1 / $num2

# Display results
Write-Host ""
Write-Host "====== Results ======" -ForegroundColor Yellow
Write-Host "$num1 + $num2 = $sum" -ForegroundColor Green
Write-Host "$num1 - $num2 = $difference" -ForegroundColor Green
Write-Host "$num1 × $num2 = $product" -ForegroundColor Green
Write-Host "$num1 ÷ $num2 = $quotient" -ForegroundColor Green
Write-Host ""
Write-Host "Thanks for calculating!" -ForegroundColor Cyan

▶️ Sample Output

Example with inputs 10 and 5:

====== Simple Calculator ====== Enter first number: 10 Enter second number: 5 ====== Results ====== 10 + 5 = 15 10 – 5 = 5 10 × 5 = 50 10 ÷ 5 = 2 Thanks for calculating!

🎨 3 Ways to Customize

Add modulo operation: Show remainder with $((num1 % num2))
Add exponentiation: Calculate $((num1 ** num2)) (num1 to the power of num2)
Check for division by zero: Add a warning if num2 is 0 before dividing

⚠️ Common Mistakes

Forgetting $(( )) in Bash: Math operations need double parentheses
Not converting to numbers (PowerShell): Input is text by default—convert with [int]
Division by zero: If user enters 0 as second number, division fails
Integer division: 10 / 3 = 3 (not 3.33) unless you handle decimals specially

✅ Success Criteria

You’ve succeeded if:

All four operations calculate correctly
Results match what you’d expect from a calculator
Script works with different number combinations

Script #5

File Creator Easy

📝 Create a new text file with user-provided content

🎯

What You’ll Learn File creation, writing to files

⏱️

Estimated Time 12 minutes

🔧

Tools Needed Terminal/PowerShell

🎓 Concepts Covered

Creating files from scripts
Writing text to files
File redirection (>, >>)
Working with file paths

💻 Complete Code

Bash (file_creator.sh)

#!/bin/bash
# Create a file with user content

echo "====== File Creator ======"
echo ""

read -p "Enter filename (e.g., mynotes.txt): " filename
read -p "Enter file content: " content

# Create the file with content
echo "$content" > "$filename"

if [ -f "$filename" ]; then
    echo ""
    echo "✓ File '$filename' created successfully!"
    echo "Content: $content"
    echo "Location: $(pwd)/$filename"
else
    echo "✗ Error: Failed to create file"
fi

PowerShell (file_creator.ps1)

# Create a file with user content

Write-Host "====== File Creator ======" -ForegroundColor Cyan
Write-Host ""

$filename = Read-Host "Enter filename (e.g., mynotes.txt)"
$content = Read-Host "Enter file content"

# Create the file with content
$content | Out-File $filename

if (Test-Path $filename) {
    Write-Host ""
    Write-Host "✓ File '$filename' created successfully!" -ForegroundColor Green
    Write-Host "Content: $content"
    Write-Host "Location: $(Get-Location)\$filename"
}
else {
    Write-Host "✗ Error: Failed to create file" -ForegroundColor Red
}

▶️ Sample Output

Example interaction:

====== File Creator ====== Enter filename (e.g., mynotes.txt): test.txt Enter file content: This is my first file! ✓ File ‘test.txt’ created successfully! Content: This is my first file! Location: /home/user/test.txt

🎨 3 Ways to Customize

Add timestamp: Include creation date/time in the file
Multiple lines: Allow user to enter multiple lines of content
Choose directory: Let user specify where to save the file

⚠️ Common Mistakes

Overwriting files: Using > replaces existing files—check if file exists first
Special characters in filename: Avoid spaces and symbols like /, \, :, *, ?
File permissions: Make sure you have write permission in the directory

✅ Success Criteria

You’ve succeeded if:

A new file appears in your directory
Opening the file shows the content you entered
Success message displays the correct file path

Script #6

File Info Display Easy

📝 Show detailed information about a file

🎯

What You’ll Learn File properties, conditionals

⏱️

Estimated Time 15 minutes

🔧

Tools Needed Terminal/PowerShell

🎓 Concepts Covered

Checking if files exist
Reading file properties (size, date)
Basic if-statements
File tests and conditions

💻 Complete Code

Bash (file_info.sh)

#!/bin/bash
# Display file information

echo "====== File Information Display ======"
echo ""

read -p "Enter filename: " filename

if [ -f "$filename" ]; then
    echo ""
    echo "File: $filename"
    echo "Size: $(wc -c < "$filename") bytes"
    echo "Lines: $(wc -l < "$filename")"
    echo "Words: $(wc -w < "$filename")"
    echo "Modified: $(stat -c %y "$filename" 2>/dev/null || stat -f %Sm "$filename")"
    echo ""
    echo "--- First 5 lines ---"
    head -5 "$filename"
else
    echo "✗ Error: File '$filename' not found"
fi

PowerShell (file_info.ps1)

# Display file information

Write-Host "====== File Information Display ======" -ForegroundColor Cyan
Write-Host ""

$filename = Read-Host "Enter filename"

if (Test-Path $filename) {
    $file = Get-Item $filename
    $content = Get-Content $filename
    
    Write-Host ""
    Write-Host "File: $($file.Name)" -ForegroundColor Yellow
    Write-Host "Size: $($file.Length) bytes"
    Write-Host "Lines: $($content.Count)"
    Write-Host "Modified: $($file.LastWriteTime)"
    Write-Host ""
    Write-Host "--- First 5 lines ---" -ForegroundColor Cyan
    $content | Select-Object -First 5
}
else {
    Write-Host "✗ Error: File '$filename' not found" -ForegroundColor Red
}

▶️ Sample Output

Example output:

====== File Information Display ====== Enter filename: test.txt File: test.txt Size: 245 bytes Lines: 8 Words: 42 Modified: 2025-10-13 14:30:22 — First 5 lines — This is line 1 This is line 2 This is line 3 This is line 4 This is line 5

🎨 3 Ways to Customize

Show last lines: Display the last 5 lines instead of first
Calculate MB/GB: Convert bytes to megabytes for large files
File type detection: Identify if it’s a text file, image, etc.

⚠️ Common Mistakes

File doesn’t exist: Always check with -f (Bash) or Test-Path (PowerShell)
Binary files: Don’t try to read binary files as text (images, executables)
File paths with spaces: Always quote variables: “$filename”

✅ Success Criteria

Script correctly identifies when file exists or doesn’t
All file properties display accurately
First 5 lines show correctly for text files

📚 Complete Script Index

Your complete learning journey from beginner to confident scripter

🎯 Scripts 1-5: Fundamentals

Hello World – Basic output (5 min)
Personal Greeting – Variables (8 min)
Interactive Echo – User input (10 min)
Simple Calculator – Math operations (12 min)
File Creator – File writing (12 min)

🎯 Scripts 6-10: File Operations

File Info Display – Reading properties (15 min)
Multiple File Creator – Loops basics (18 min)
File Organizer – Loops + conditions (20 min)
Text Search – String searching (20 min)
Backup Script – Copying with timestamps (25 min)

🎯 Scripts 11-15: Intermediate Skills

Log File Cleaner – File deletion logic (25 min)
Disk Space Monitor – System info (30 min)
Process Lister – System processes (30 min)
Password Generator – Random data (25 min)
To-Do List Manager – File read/write/append (35 min)

🎯 Scripts 16-20: Advanced Integration

User Account Creator – Input validation (40 min)
System Health Report – Multiple checks (45 min)
Automated Backup – Combining concepts (50 min)
Log Analyzer – Text processing (50 min)
Multi-Tool Menu – Complete application (60 min)

🎓 Learning Path Summary

Total Time: ~9 hours of hands-on practice
Progression: Each script builds on previous concepts
By Script 20: You’ll have a complete toolset of reusable scripts
Skill Level: From absolute beginner to confident scripter

✅ What You’ll Achieve

After completing all 20 scripts, you will be able to:

Write scripts confidently in both Bash and PowerShell
Automate everyday tasks and save hours of work
Handle files, directories, and system operations
Create interactive tools with menus and user input
Debug common errors and customize existing scripts
Read and understand other people’s scripts
Build your own automation tools from scratch

Bash & PowerShell Scripting Part-2

📚 20 Scripts Every Beginner Should Write

Hello World Beginner

🎓 Concepts Covered

📋 Step-by-Step Instructions

💻 Complete Code

▶️ Sample Output

🎨 3 Ways to Customize

⚠️ Common Mistakes

✅ Success Criteria

Personal Greeting Beginner

🎓 Concepts Covered

📋 Step-by-Step Instructions

💻 Complete Code

▶️ Sample Output

🎨 3 Ways to Customize

⚠️ Common Mistakes

✅ Success Criteria

Interactive Echo Beginner

🎓 Concepts Covered

📋 Step-by-Step Instructions

💻 Complete Code

▶️ Sample Output

🎨 3 Ways to Customize

⚠️ Common Mistakes

✅ Success Criteria

Simple Calculator Easy

🎓 Concepts Covered

📋 Step-by-Step Instructions

💻 Complete Code

▶️ Sample Output

🎨 3 Ways to Customize

⚠️ Common Mistakes

✅ Success Criteria

File Creator Easy

🎓 Concepts Covered

💻 Complete Code

▶️ Sample Output

🎨 3 Ways to Customize

⚠️ Common Mistakes

✅ Success Criteria

File Info Display Easy

🎓 Concepts Covered

💻 Complete Code

▶️ Sample Output

🎨 3 Ways to Customize

⚠️ Common Mistakes

✅ Success Criteria

📚 Complete Script Index

🎯 Scripts 1-5: Fundamentals

🎯 Scripts 6-10: File Operations

🎯 Scripts 11-15: Intermediate Skills

🎯 Scripts 16-20: Advanced Integration

🎓 Learning Path Summary

✅ What You’ll Achieve

🎉 Congratulations on Your Learning Journey!