public function add($key, $value, $ttl = 259200, $tags = NULL)
{
if (empty($key) || $value == NULL) {
$this->ReportError('empty keys and values are not allowed', __LINE__);
return false;
}
$key = (string) $key;
$auto_unlocker = NULL;
if (!$this->mutex->get_access_write($auto_unlocker)) {
return false;
}
$map = $this->mem_object->read('map');
if (isset($map[$key])) {
return false;
}
return $this->save($key, $value, $ttl, $tags);
}