<?php Swoole\Server->protect(int $fd, bool $value = true)
The file descriptor ID that you want to protect from being closed from heartbeat checks.
true to stop the fd from being closed and set to
false to remove the protection from being closed.
true is returned, otherwise
$fd (file descriptor) from being closed by the heartbeat check interval. Use
$value to set or remove this protected state from a client connection.