Calling Drupal functions in external PHP file

Question

How can I call a Drupal function or get the global variable in a PHP file which is located under the drupal installation folder. I doing it for the first time. Are there any

Answer 1

define('DRUPAL_ROOT', getcwd());
require_once './includes/bootstrap.inc';
drupal_bootstrap(DRUPAL_BOOTSTRAP_FULL);

The above code works for me, when the script is in my Drupal root directory. This loads absolutely everything, not just Drupal core, including contributed module hooks.