process.stdin and process.stdout in Node.js - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is process.stdin in Node.js?

process.stdin is a readable stream that lets your Node.js program receive input from the user through the terminal or command line.

beginner

What does process.stdout do in Node.js?

process.stdout is a writable stream that allows your program to send output to the terminal or command line, showing messages or results to the user.

intermediate

How do you listen for user input using process.stdin?

You attach a listener to the data event on process.stdin. This event fires whenever the user types something and presses enter.

process.stdin.on('data', (input) => { console.log(`You typed: ${input}`); });

beginner

How can you write a message to the terminal using process.stdout?

You use the write() method on process.stdout to send text to the terminal without adding a new line automatically.

process.stdout.write('Hello, user!');

intermediate

Why might you use process.stdin.setEncoding('utf8')?

This sets the input encoding so that the data you receive from process.stdin is a readable string instead of raw bytes, making it easier to work with text input.

What type of stream is process.stdin in Node.js?

A Writable stream

B Transform stream

C Duplex stream

D Readable stream

process.stdin is a readable stream because it reads input from the user.

Which method do you use to send output to the terminal with process.stdout?

A write()

B read()

C on()

D pipe()

write() sends data to the terminal through process.stdout.

How do you listen for user input from the terminal in Node.js?

A process.stdout.on('data', callback)

B process.stdin.on('data', callback)

C process.stdin.write('data')

D process.stdout.write('data')

You listen to the data event on process.stdin to get user input.

What does process.stdin.setEncoding('utf8') do?

A Converts input to a string

B Converts output to uppercase

C Stops input from being read

D Changes output color

It sets the input encoding so data is received as a string, not raw bytes.

Which of these is true about process.stdout.write()?

A It automatically adds a new line

B It never outputs to the terminal

C It writes text to the terminal without a new line

D It reads user input

write() outputs text but does not add a new line automatically.

Explain how process.stdin and process.stdout work together in a Node.js program.

Think about how your program talks and listens in the terminal.

Describe how to set up a simple Node.js program that asks the user for their name and then greets them.

Imagine a friendly chat with the user in the terminal.