Dns resolv exceptions

I am using the DNS::Resolv class to work with some dns data.

I am having a hard time understanding how the exception handling is
supposed to work and how certain situations should be handled.

For example, how are timeouts against the dns server handled? There are
several references to ResolvTimeout exception however when resolving
different names or addresses I have yet to see it be thrown. Even
against a dns server address that is clearly not resolving!

Any insight would be great. I would be happy to give more detail if
needed.

Thanks!