有几种选项可以设置消息发送模式，优先级和存活时间值。

There are options to set message delivery mode, priority and time-to-live value.

youdao

设置套接字的IP _TTL选项，TTL表示“存活时间”，但是在这个上下文环境中，特指一个数据包允许经过的IP跳数。

Sets the IP_TTL socket option. TTL stands for "Time to Live," but in this context it specifies the number of IP hops that a packet is allowed to go through.

youdao

设置在此多播套接字发出的多播包的默认存活时间以便控制多播的作用域。

Set the default time-to-live for multicast packets sent out on this MulticastSocket in order to control the scope of the multicasts.

youdao

设置在此多播套接字发出的多播包的默认存活时间以便控制多播的作用域。

Set the default time-to-live for multicast packets sent out on this MulticastSocket in order to control the scope of the multicasts.

youdao