src/Listener.php
public function notify() {
			declare(ticks=1);
			if (is_array($this->_caller) && !empty($this->_caller)) {
				// array
				return call_user_func_array($this->_caller, [$this->_interrupt]);
			} else if ($this->_caller instanceof Closure) {
				// closure
				return $this->_caller->call($this, $this->_interrupt);
			} else if (is_callable($this->_caller)) {
				// callable
				$cl = Closure::fromCallable($this->_caller);
				return $cl->call($this,$this->_interrupt);
			}
			return null;
		}
public function notify() {
			declare(ticks=1);
			if (is_array($this->_caller) && !empty($this->_caller)) {
				// array
				return call_user_func_array($this->_caller, [$this->_interrupt]);
			} else if ($this->_caller instanceof Closure) {
				// closure
				return $this->_caller->call($this, $this->_interrupt);
			} else if (is_callable($this->_caller)) {
				// callable
				$cl = Closure::fromCallable($this->_caller);
				return $cl->call($this,$this->_interrupt);
			}
			return null;
		}
Called on interruption
@return null|int