src/Socket.php
public function listen($backlog = 4) {
		socket_bind($this->socket, $this->ip, $this->port);
		socket_listen($this->socket, $backlog); // 4条等待
        return $this;
	}
public function listen($backlog = 4) {
		socket_bind($this->socket, $this->ip, $this->port);
		socket_listen($this->socket, $backlog); // 4条等待
        return $this;
	}
服务端
@param int|number $backlog