Chapter 2: Handling I/O

Prior to Node.js, JavaScript was predominantly used in the browser. Node.js brought JavaScript to the server and has enabled us to interact with the operating system with JavaScript. Today, Node.js is one of the most popular technologies for building server-side applications.

Node.js interacts with the operating system at a fundamental level: input and output. This chapter will explore the core APIs provided by Node.js that allow us to interact with the standard I/O, the file system, and the network stack.

This chapter will show you how to read and write files both synchronously and asynchronously. Node.js was built to handle asynchronous code and enable a non-blocking model. Understanding how to read and write asynchronous code is key learning, and it will show how to leverage the capabilities of Node.js.

We will also learn about the core modules provided by Node.js. We'll be focusing on the File System module, which enables you to interact with the file system and files.

This chapter will cover the following recipes:

• Handling standard I/O
• Managing files with fs module
• Inspecting file metadata
• Watching for file updates
• Creating TCP server and client communication