I have access to the code. There is no more reliable reference. The source code is remarkably well organized and clearly coded and has massive amounts of unit tests.
The biggest difference between 6.6 and 7.0 in the kernel is mostly that SMP is always enabled and 64-bit targets are first-class citizens. There are plenty of minor changes, but the kernel itself is very, very small.
There are plenty of changes to the userspace runtime, but the question was about the kernel.
Oh, also, 7.0 has an ISO 26262 certified variant. Not a technical difference, but an important one.
Hi! I have a couple questions I've been wondering about for years. Appreciate any insight/answers you can provide.
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QNX was momentarily open for a little while until the license change with BlackBerry et al. My question: did this license change only apply to future QNX versions, or did it also retroactively apply to the "open"-sourced code as well?
My primary current interest in QNX stems from being fascinated with old and/or unusual operating systems. I'd love to be able to go fishing for 6.4 et al, maybe even compile what I find from source (or maybe not), and basically just play with the system to see how it works. If it's fine for me to go and find 6.4 and poke at it for noncommercial purposes - well, that'd be awesome to know. Obviously such a usage model would not incorporate any official agreement or warranty, and I understand that.
In a somewhat related vein, at some point I may find it useful to observe how QNX handles certain technical minutiae as part of my own (hopeful) OS development work. Obviously sourcing the latest versions of the QNX source for this purpose would offer support options, not to mention a more relevant codebase; but it would be great to know that I'd be able to safely make do with the older releases as long as I don't seek/expect any form of support.
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I was unfortunately out of the loop with the QNX scene during the period it was open so I never got a chance to grab any of the repos. (And a quick search turned up what appears to be some QNX 6.4 bits and pieces on GitHub (as the previous comment hinted at) but it doesn't look very official, so I don't want to sift through it in case I waste my time.) Of course official repo access has since been closed, so I can't check that. So: I figure why not ask, what can it hurt.
When the repo was opened, did it include full commit history, or a large portion of it?
QNX 4.x is really cool. I managed to get an old copy working in a VM some time ago (took a bit of thinking; there's so little documentation out there). 6.x is nicer, but 4.x feels faster (which kind of makes sense).
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I've been fascinated with QNX for years, and to be honest I want to say I find the "closed > yay open!! > closed" timeline incredibly frustrating; but besides wistfulness, this has also generated a fair bit of confusion regarding the current status quo.
I can tell you some of that. We ported all our applications from QNX6.5 to QNX6.6 and then QNX7.0.
They deprecated some POSIX calls like posix_spawn_file_actions_addopen (at least in QNX6.6 documentation they mention it's not fully implemented and it is indeed broken).
They made the QNX7.0 kernel instrumented-only (there are no longer non-instrumented versions).
They changed lots of low level stuff that is outside the kernel, like throwing out photon and replacing it with screen library, completely replacing the PCI server, making changes to the console, security patches, and so on. But since it's a microkernel, this is mostly in userland.
