'Init.
name: name for the switch
dpopts: additional arguments to ofdatapath (--no-slicing)'

def __init__(self, name, dpopts='--no-slicing', **kwargs):

    Switch.__init__(self, name, **kwargs)
    pathCheck('ofdatapath', 'ofprotocol', moduleName=('the    OpenFlow    reference    user    switch' + '(openflow.org)'))
    if self.listenPort:
        self.opts += ('    --listen=ptcp:%i    ' % self.listenPort)
    else:
        self.opts += ('    --listen=punix:/tmp/%s.listen' % self.name)
    self.dpopts = dpopts
