IPC communication between processes in Node.js - Cheat Sheet & Quick Revision

Recall & Review

beginner

What does IPC stand for in Node.js?

IPC stands for Inter-Process Communication. It allows different processes to talk and share data with each other.

beginner

Name two common ways Node.js processes communicate using IPC.

1. Using child process's built-in messaging with process.send() and process.on('message').<br>2. Using sockets or named pipes for more complex communication.

beginner

How do you send a message from a parent process to a child process in Node.js?

Use child.send(message) where child is the child process object created by fork().

beginner

What event do you listen to in a child process to receive messages from the parent?

Listen to the 'message' event on process inside the child process, like process.on('message', (msg) => { ... }).

beginner

Why is IPC useful in Node.js applications?

IPC helps split work into multiple processes to improve performance and reliability. Processes can share data and coordinate tasks without blocking each other.

Which Node.js method sends a message from a child process to its parent?

A process.emit()

B process.send()

C child.send()

D child.emit()

In a child process, use process.send() to send messages to the parent.

What event should a parent process listen to receive messages from a child?

A 'message' event on process object

B 'data' event on process object

C 'send' event on child process

D 'message' event on child process object

The parent listens to the 'message' event on the child process object to get messages.

Which Node.js module is commonly used to create child processes for IPC?

A fs

B http

C child_process

D events

The child_process module provides methods like fork() to create child processes.

What does the fork() method do in Node.js?

A Creates a new child process with IPC channel

B Creates a new thread

C Starts a web server

D Reads a file asynchronously

fork() creates a child process with a communication channel for IPC.

Why might you use IPC instead of sharing variables directly between processes?

A Because processes do not share memory

B Because IPC is faster than variables

C Because variables are deprecated

D Because IPC uses global variables

Processes have separate memory, so IPC is needed to exchange data safely.

Explain how a parent and child process communicate using IPC in Node.js.

Think about how messages are sent and received between processes.

Describe why IPC is important when working with multiple Node.js processes.

Consider what happens when processes run independently but need to work together.