> No, because this thing, darwin-xnu AKA the OSX/iOS microkernel, was already opensourced through https://opensource.apple.com/ for both iOS and OSX

This is not true. iOS components were always stripped out until now.

This, while probably seemingly unimportant to a lot of people, is extremely great news for a project I'm a part of!

We're working on a full iPhone emulator based on QEMU, and currently, while we are able to boot into early userspace from an unmodified iOS image, the release of the iOS-specific code will be quite helpful in speeding up bug elimination and the development of the virtual graphics hardware that can get us past a basic graphical framebuffer.

wow, interesting! Where can I find your project?

Probably this:

https://github.com/joshumax/QEMU-s5l89xx-port

Or this:

https://github.com/nvsio/qemu-ios

Found sort of via this:

https://www.reddit.com/r/jailbreak/comments/6crw5t/question_...

I assume they won't mind my sharing. They posted it publicly with the same username and have public Git pages.

Actually, you saved me a post! Thanks!

Although quick note, a lot of work is being done in a private repo until it passes the "clean room" test, after which it will be pushed to the public repos. :)

You've incredible search skills! Thank you very much =))

Minor correction: XNU is not a microkernel.

XNU is a hybrid kernel incorporating large elements of Mach (microkernel) as well as BSD (monolithic kernel).

The term "hybrid" is not a particularly useful concept, since the whole idea of a microkernel is to achieve stability and extensibility by placing only a minimal kernel in kernel space, and have everything else (drivers, file system, etc.) live in userland.

XNU is built on Mach (initially 2.x back when it was NeXTStep/OpenStep, later 3.0 for OS X), but everything runs in a single address space. Mach ports are retained throughout the OS as a communication mechanism, including userland, but all the core stuff is in the kernel, and Apple has transitioned many Mach port IPC responsibilites to more traditional syscalls to work around the fact that ports are comparatively slow. For example, all POSIX operations such as read and write are BSD syscalls that correspond to entrypoints in the kernel; they're not IPC messages.

That‘s true, but it‘s also important to note that most of the BSD subsystem is actually a shim over Mach. So once your BSD syscall has made it to the kernel, chances are you‘ll get a mach IPC call from the BSD shim.

The term "hybrid kernel" means it elegantly combines the disadvantage of a Mach microkernel (slow IPC based interfaces) with the disadvantage of a monolithic kernel (no fault tolerance due to single address space).

Apple using GitHub isn't new, they've been doing it for at least a couple of years. ResearchKit was their first GitHub repository I think.

Isn’t it Swift?