On Mon, May 22, 2006, Manu Abraham wrote: > Johannes Stezenbach wrote: > >Anyway, one last try. Let's go back to the very beginning: > > > >- we need to extend frontend API for DVB-S2, DVB-H etc. > > > >- we cannot do so without breaking backward compatibility > > because of mistakes made when defining the current API > >- so now that we define new API, we don't want to repeat > > the same mistake, but design in a way that make future > > extensions possible without too much pain for > > driver and application developers > > > >- right from the beginning my position was to do the > > *minimal* work necessary to support the *current* > > requirements -- keep it simple and stupid > >- and add other stuff later when the need arises > >- and all along you totally ignored this and instead > > want to cram every last detail into the API that > > you think *might* be necessary > >- wrt requirements: you need to think through how > > an application will work (how does dvbscan discover > > DVB-S2 transmission? where do the tuning parameters > > come from?) > > currently the tuning parameters come from the > s2_satellite_delivery_system_descriptor > what i have in there is the sis-mis flag and the transport stream > identifier to select the streams Anyone seen a s2_satellite_delivery_system_descriptor in any broadcast? There are DVB-S2 braodcasts on Astra 19.2E, do they have s2_satellite_delivery_system_descriptors? > >Remember: You cannot remove anything from the API > >once it is in there. But you can always add stuff later. > > > >Please ask yourself who are doing this API design for, and > >how people are going to benefit from your work. > >IMHO: > >- users just expect to be able to buy a DVB-S2 card and > > watch the services broadcast *today* via DVB-S2 > >- application developers want to support DVB-S2 with > > as little hassle as possible > > > >With the new API "as little hassle as possible" for > >apps already means: > >- testing for support for the new API > >- fallback to using the old API for backwards compatibility > > > >:-( > > > >IMHO it is of no use to further complicate the matter by > >adding lots of unnecessary stuff to the API. > > Johannes, you are just accusing me with blunt statements like that. I > really don't know what to say on your accusations. There isn't any accusation or "blunt statement" in my writing. I just wanted to give you stuff to think about. I asked myself those questions and reached some conclusions (which I think were reflected in my postings already). Those questions should show you how I reached my conclusions, so you can folloow them. > I too agree with not adding unwanted stuff into the API. Good. > >BTW, I don't claim to be right on my interpretation of the > >DVB-S2 spec, however as long as we can't agree (i.e. > >no one can give a good explanation why his version > >of the DVB-S2 API is the correct one, and *everyone* > >can agree on it), I think the while DVB-S2 API is useless. > > Are there any other versions ? There are few different versions of your proposal, and my proposal, and Felix' or Mws' original proposal. Johannes _______________________________________________ linux-dvb@xxxxxxxxxxx http://www.linuxtv.org/cgi-bin/mailman/listinfo/linux-dvb
