+ // Assure that there are no tasks executed twice
+ $id = q("SELECT `id` FROM `workerqueue` WHERE `id` = %d AND `pid` = %d",
+ intval($r[0]["id"]),
+ intval(getmypid()));
+ if (!$id) {
+ logger("Queue item ".$r[0]["id"]." was executed multiple times - skip this execution", LOGGER_DEBUG);
+ continue;
+ }
+