Checking variables - actions for VBO and other modules

If you are creating some actions for VBO module, so you can do some operations on fields over view. You would probably first check what is there to fetch in object you are using. So for example to get a listing of user objects variables you make this submodule

function profilecopy_action_info() {
  return array('profilecopy_action' => array(
    'type' => 'user',
    'description' => t('Get profile data'),
    'configurable' => FALSE,
  ));
}

function profilecopy_action(&$user, $context) {
 drupal_set_message('
'.print_r($user, TRUE).'
');

}

And this will list all the variables there are for user you select in VBO list and then you can code further what ever you need.