Blocks until the server finishes, i.e. a serious problem occurred or the
cancellation request has been triggered.
Server implementations are expected to implement cancellation in a best-
effort way – usually, it should be possible to immediately stop accepting
connections and return after all currently active clients have been
processed, but this might not be the case for every conceivable
implementation.
Starts serving.
Blocks until the server finishes, i.e. a serious problem occurred or the cancellation request has been triggered.
Server implementations are expected to implement cancellation in a best- effort way – usually, it should be possible to immediately stop accepting connections and return after all currently active clients have been processed, but this might not be the case for every conceivable implementation.