src/Worker.php
public function start()
    {
    	if (!$this->simulation) {
			$sockets = [];
			socket_create_pair(AF_UNIX, SOCK_STREAM, 0, $sockets);
			$pid = getmypid();

			$this->pid = $this->forkThread([$this, 'onWorkerStart'], [$sockets[1], $pid]);
			$this->toChild = $sockets[0];
			socket_set_nonblock($this->toChild);
		}
    }
public function start()
    {
    	if (!$this->simulation) {
			$sockets = [];
			socket_create_pair(AF_UNIX, SOCK_STREAM, 0, $sockets);
			$pid = getmypid();

			$this->pid = $this->forkThread([$this, 'onWorkerStart'], [$sockets[1], $pid]);
			$this->toChild = $sockets[0];
			socket_set_nonblock($this->toChild);
		}
    }
Starts a worker and begins listening for incoming payload.
This method should not be invoked when new object is constructing
because a Worker can be cloned before starting working.
@throws \Exception