File Streams

Streams process data piece by piece — efficient for large files.

Syntax

NODEJS

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const fs = require('fs');

const readStream = fs.createReadStream('large.txt');
const writeStream = fs.createWriteStream('copy.txt');

readStream.pipe(writeStream);

File Streams

NODE

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const fs = require("fs");

fs.writeFileSync("large-file.txt", "Streaming data line by line");

// Read stream
const readStream = fs.createReadStream("large-file.txt", "utf-8");
readStream.on("data", (chunk) => {
    console.log("Received chunk:", chunk.length);
});
readStream.on("end", () => {
    console.log("Finished reading");
});

// Write stream
const writeStream = fs.createWriteStream("output.txt");
writeStream.write(`Line 1
`);
writeStream.write(`Line 2
`);
writeStream.end();

Try It Yourself

Practice

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Exercise

Practice this concept.

Answer

Write the code as shown above.

Quick Quiz

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What did you learn?

Concept A

Concept B

Concept C

Concept D

This covers the basics.

Retry Quiz

Interview Questions

Explain this concept.

It is a fundamental Node.js feature.

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Reading & Writing Files

Tutorial Complete

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