How to open files on a system with nodejs code example

Example 1: node open file

const fs = require("fs");

// __dirname means relative to script. Use "./data.txt" if you want it relative to execution path.
fs.readFile(__dirname + "/data.txt", (error, data) => {
    if(error) {
        throw error;
    }
    console.log(data.toString());
});

Example 2: nodejs open file

fs = require('fs')
fs.readFile('/etc/hosts', 'utf8', function (err,data) {
  if (err) {
    return console.log(err);
  }
  console.log(data);
});