readme.md

Day 04

Introduction

Building and running a shell script

Challenges

Challenge 1: Hello World and Basic Commands

Objective: Write your first shell script and learn basic commands.

Tasks:

1. Open your terminal.
2. Create a new directory called shell_scripting and navigate into it.
3. Create a file named hello_world.sh.
4. Use a text editor (like nano or vim) to add the following script to the file:

   #!/bin/bash
   echo "Hello, World!"

5. Make the script executable with the command chmod +x hello_world.sh.
6. Run the script using ./hello_world.sh.
7. Modify the script to also print the current date and time.

Challenge 2: Variables and User Input

Objective: Learn to use variables and take user input in a shell script.

Tasks:

1. Create a new file named greet_user.sh.
2. Write a script that asks the user for their name and greets them:

   #!/bin/bash
   echo "What is your name?"
   read name
   echo "Hello, $name! Nice to meet you."

3. Make the script executable and run it.
4. Extend the script to ask for the user's age and print it along with the greeting.

Challenge 3: Conditional Statements

Objective: Use conditional statements to control the flow of your script.

Tasks:

1. Create a new file named check_age.sh.
2. Write a script that asks the user for their age and checks if they are eligible to vote (age 18 or older):

   #!/bin/bash
   echo "How old are you?"
   read age
   if [ "$age" -ge 18 ]; then
       echo "You are eligible to vote."
   else
       echo "You are not eligible to vote yet."
   fi

3. Make the script executable and run it.
4. Modify the script to also check if the user is a teenager (age between 13 and 19).

Challenge 4

Loops and Functions

Objective: Learn to use loops and functions in your shell script.

Tasks:

1. Create a new file named countdown.sh.
2. Write a script that counts down from 5 to 1 and then prints "Blast off!":

   #!/bin/bash
   for ((i=5; i>=1; i--)); do
       echo $i
       sleep 1
   done
   echo "Blast off!"

3. Make the script executable and run it.
4. Add a function to the script that prints a custom message before the countdown starts. Call this function at the beginning of the script.

By completing these four parts, you'll have a good understanding of the basics of shell scripting, including writing scripts, using variables, taking user input, conditional statements, loops, and functions. Good luck!

Challenge 5

Come up with your own script and what would you like a script to do?
We are curious about what you like to run in a script!