mediumLow-Level Design

Explain the differences between fork(), spawn(), and exec() in the child_process module.

Q: Explain the differences between fork(), spawn(), and exec() in the child_process module.

**TL;DR.** All three create **child processes** but differ in I/O and intent. spawn launches a process and **streams** its output (great for large/long output). exec runs a command **in a shell** and **buffers** the whole output to a callback (good for short commands). fork is a specialized spawn for **Node modules**, adding an **IPC channel** for message passing. spawn streams stdout no shell exec <text class='

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Contrast the three primary ways to spawn child processes in Node.js.

child-processconcurrencyperformance

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All three

import { spawn, exec, fork } from 'node:child_process';

// spawn: stream output
const ls = spawn('ls', ['-la']);
ls.stdout.on('data', d => process.stdout.write(d));

// exec: buffer to callback (beware maxBuffer + shell injection)
exec('git rev-parse HEAD', (err, stdout) => console.log(stdout.trim()));

// fork: run a Node script with IPC
const child = fork('./worker.js');
child.send({ task: 'crunch' });
child.on('message', (msg) => console.log('from child:', msg));

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