'If we\'re asked to disconnect (and we haven\'t already) shut down
the C{ProcessProtocol} with a 0 exit code.'

def loseConnection(self):

    if self.closed:
        return
    self.closed = 1
    self.proto.inConnectionLost()
    self.proto.outConnectionLost()
    self.proto.errConnectionLost()
    self.proto.processEnded(failure.Failure(error.ProcessTerminated(0, None, None)))
