First Bash script in Bash Scripting - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the first line in a Bash script that tells the system which interpreter to use?

The first line is called the shebang. It looks like #!/bin/bash and tells the system to use the Bash shell to run the script.

beginner

How do you make a Bash script executable?

Use the command chmod +x scriptname.sh to give execute permission to your script.

beginner

What command runs a Bash script named hello.sh in the current directory?

Run the script with ./hello.sh if it has execute permission.

beginner

What does this simple Bash script do?

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

It prints the text Hello, world! to the screen.

beginner

Why is it important to save your Bash script with a .sh extension?

The .sh extension helps you and others recognize the file as a shell script, but it is not required for execution.

What does the shebang line #!/bin/bash do in a Bash script?

A Comments out the line

B Specifies the script interpreter

C Runs the script automatically

D Defines a variable

The shebang line tells the system which program to use to run the script.

Which command makes a Bash script executable?

A chmod +x script.sh

B run script.sh

C bash script.sh

D edit script.sh

The chmod +x command adds execute permission to the script.

How do you run a Bash script named myscript.sh in the current folder?

A myscript.sh

B execute myscript.sh

C bash run myscript.sh

D ./myscript.sh

Use ./myscript.sh to run the script if it has execute permission.

What does the command echo "Hello" do in a Bash script?

A Deletes Hello

B Creates a file named Hello

C Prints Hello to the screen

D Runs a program called Hello

The echo command prints text to the screen.

Is the .sh extension required to run a Bash script?

A No, but it helps identify the file

B Yes, it is required

C Only on Windows

D Only if the script is large

The extension is not required but is a helpful convention.

Describe the steps to create and run your first Bash script.

Think about writing, saving, permission, and running.

Explain the purpose of the shebang line in a Bash script and what happens if it is missing.

Focus on interpreter selection and script execution.