Rename a file by incrementing its number

rename.js

var fs = require('fs'),
  schedule = require('node-schedule'),
  currentfilename = '/Users/gabrielstuff/Desktop/default/iehg',
  newFilename = '/Users/gabrielstuff/Desktop/default/video',
  extension = 'mp4',
  number = 0;

function rename() {
  fs.rename(currentfilename+'.' + extension, newFilename + '_' + number + '.' + extension, function(err) {
    if (err) {
      console.log('error moving: ' + err);
    }
    currentfilename = newFilename + '_' + number;
    number++;
  });
}

var readline = require('readline');

var rl = readline.createInterface({
  input: process.stdin,
  output: process.stdout
});

// Just to keep the console open
rl.question("What do you think of node.js? ", function(answer) {
  console.log("Thank you for your valuable feedback:", answer);
  rl.close();
});

setInterval(function(){
  rename();
}, 120000);

rename();