fails:Socket#getservbyname returns the port for service 'http'
fails:Socket#getservbyname returns the port for service 'http' with protocol 'tcp'
fails:Socket#getservbyname returns the port for service 'domain' with protocol 'udp'
fails:Socket#getservbyname returns the port for service 'daytime'
fails:Socket#getservbyname raises a SocketError when the service or port is invalid
