'Internal parser function for L{_parseServer} to convert the string
arguments for a systemd server endpoint into structured arguments for
L{AdoptedStreamServerEndpoint}.
@param reactor: An L{IReactorSocket} provider.
@param domain: The domain (or address family) of the socket inherited
from systemd.  This is a string like C{"INET"} or C{"UNIX"}, ie the
name of an address family from the L{socket} module, without the
C{"AF_"} prefix.
@type domain: C{str}
@param index: An offset into the list of file descriptors inherited from
systemd.
@type index: C{str}
@return: A two-tuple of parsed positional arguments and parsed keyword
arguments (a tuple and a dictionary).  These can be used to
construct an L{AdoptedStreamServerEndpoint}.'

def _parseServer(self, reactor, domain, index):

    index = int(index)
    fileno = self._sddaemon.inheritedDescriptors()[index]
    addressFamily = getattr(socket, ('AF_' + domain))
    return AdoptedStreamServerEndpoint(reactor, fileno, addressFamily)
