Hello Marcel, On Wed, 2006-03-22 at 18:55 +0100, Marcel Siegert wrote: > chose to have ioctls numbered NOT with the __FE_[GET|SET]_FRONTEND_OLD numbers, > after discussion with andreas oberritter. (think this needs more investigation/discussion) my last words during our conversation were that I agree with Felix that this will break compatibility for old apps which were compiled with new headers but are running on old kernels. So this is probably not an option. But I think you should write the word "HACK" next to it in large letters with flashing lights, because this style of backwards compatibility must not be copied blindly in the future. It only works in this case because the old and new structs happen to have different sizes which makes the ioctl macro create a different magic number. But the size of a structure depends on the architecture (e.g. 32 vs. 64 bit longs) and maybe on alignment restrictions. I guess there will be cases where such a change will work on an 32 bit x86 system, but won't on some other arch, let's say 64 bit alpha/sparc/ppc/mips. Maybe this has already been discussed, but in case it didn't: Why don't we leave the ioctl as it is now and introduce a new one additionally, e.g. FE_SET_FRONTEND2, and mark the old one as deprecated? Regards, Andreas _______________________________________________ linux-dvb@xxxxxxxxxxx http://www.linuxtv.org/cgi-bin/mailman/listinfo/linux-dvb
