Facebook SDK example : saving user data to file

facebook.php

<?php
function facebooklog(){
 require('/PATH_TO_FACEBOOK_PHP_SDK/src/facebook.php');

  $facebook = new Facebook(array(
   'appId' => 'YOUR_APP_ID',
   'secret' => 'YOUR_APP_SECRET',
  ));
// Get User ID
 $user = $facebook->getUser();
 if ($user) {
  try {
  $user_profile = $facebook->api('/me');
  $url = $_SERVER['REQUEST_URI'];
  $file = 'b_facebook.txt';
  $current = file_get_contents($file);
  $current .= date(r) . ";" . $user_profile[name] . ";" . $url . "\n";
  file_put_contents($file, $current);
  } catch (FacebookApiException $e) {
  $user = null;
  }
  } else {
 }
}
?>