last 'streaming' applications we wrote, some for audio processing, others for image processing, we used the source/processor/sink notion (didn't even think of u

last 'streaming' applications we wrote, some for audio processing, others for image processing, we used the source/processor/sink notion (didn't even think of using drain) - source = origin of data, sink = destination fordata, processor = data goes in and comes out again, so basically sink at input end and source at output end. But I don't think I ever saw sink to be used as a source of data.