// filereader.js
// 2015 cloudbender


var fs = require('fs');


(function main() {

  console.log('main: started');


  // the second argument to readFile is a function, to be
  // called with an error or a data argument
  // when readFile is completed or has an error.

  // readFile will schedule the callback and arguments, onto the event loop
  // to be called when node can get to it.

  var myfile = fs.readFile('myfile.txt', function(err,data){

    // we are now inside the called-back function

    if (err) {
      console.log('error reading myfile.txt');
      return;
    }
    if (data) {
      console.log('myfile.txt contains data and had no error');
      return;
    }

  });

  console.log('main: completed');
  // main will complete before readFile completes.
})();