Symfony\Component\EventDispatcher\EventDispatcher::removeListener PHP Method

    public function removeListener($eventName, $listener)
    {
        if (!isset($this->listeners[$eventName])) {
            return;
        }

        foreach ($this->listeners[$eventName] as $priority => $listeners) {
            if (false !== ($key = array_search($listener, $listeners))) {
                unset($this->listeners[$eventName][$priority][$key], $this->sorted[$eventName]);
            }
        }
    }

 public function removeSignalListener($signal, $callable)
 {
     $this->dispatcher->removeListener('morker.signal.' . $signal, $callable);
     if (!$this->dispatcher->hasListeners('morker.signal.' . $signal)) {
         pcntl_signal($signal, SIG_DFL);
     }
 }