socket and DynDNS

["Martin v. Löwis"]

> My naive and ugly alternative is to periodically (e.g. every 5
> minutes) do a manual lookup and use the last address.

You should look at the TTL of the DNS record, and re-lookup when it
expires.

There will be *no* kind of protection for UDP messages. When
the machine loses its IP address, it will stop receiving your
messages, even if they are already in transit. If the provider
re-assigns the IP address to some other customer, that customer
will receive the UDP messages instead.

If you want safety, you need to implement it in your application,
e.g. by the receiver side sending heart beat messages, and the
sender side resending everything that might have been lost since
the last heart beat.

Regards,
Martin