Couldn’t find actual release notes that point out the exact difference between QNX 6.5.1 and 6.6.0. I know that Photon’s not supported anymore.
So far, I’ve got SDP 6.6.0 but it might be that I need my software also to run on 6.5.0. So what is the actual backward compatibility level to 6.5.0? Some state that “6.6 is binary compatible with 6.5” or that they “created with 6.6, use[d] it on [their] 6.5 custom distribution and it worked”  - can anyone support this with official documents?
Since QNX follows the POSIX standard, I suppose that the APIs are the same and should be indeed provide backwards compatibility. So the programs created for 6.6.0 should basically also run on 6.5.0, right?
P.S.: You’ll find the same question posted by my friend on StackOverflow again.