public function writeTo($fd, string $data): int
    {
        return $this->server->send($fd, $data) ? 0 : 1;
    }
public function writeTo($fd, string $data): int
    {
        return $this->server->send($fd, $data) ? 0 : 1;
    }
public function writeTo ( $ fd , string $ data ) : int { return $ this -> server -> send ( $ fd , $ data ) ? 0 : 1 ; }
response data to client by socket connection
@param int $fd
@param string $data
param int $length
@return int   Return error number code. gt 0 on failure, eq 0 on success
response data to client by socket connection