'Any exception raised by the underlying write call, except for EINTR, is
propagated to the caller.'

def test_unhandledWriteError(self):

    self.port.startListening()
    tunnel = self.system.getTunnel(self.port)
    self.assertRaises(IOError, self.port.write, (('x' * tunnel.SEND_BUFFER_SIZE) + 'y'))
