[Discuss-gnuradio] UDP Sink Broadcast

Hi,

Does anybody know of a way to broadcast to a UDP Sink block?  A unicast works fine but setting the destination address to 172.168.255.255 always gives a permission denied error even when running as su.  The firewall zone for all adapters is set to "trusted."  Is there a way to set an SO_BROADCAST flag like you might do when creating a UDP socket from the Python socket module? 

Thanks,

Mark