(PECL swoole >= 1.9.0)
$force
$host
$port
$timeout
$flag
$event
$callback
$socket
$size
$data
$filename
$offset
$ip
$settings
Swoole\Client::MSG_OOB
Swoole\Client::MSG_PEEK
Swoole\Client::MSG_DONTWAIT
Swoole\Client::MSG_WAITALL