screen VS xnu

All the open source code Apple is obligated to make available is listed at https://opensource.apple.com/releases/. screen for example is included based on the GPL2 license. There are a few other projects as well, though definitely less since the so-called GPL purge

> That said--in support of "not in a vacuum", and against myth-making.

Apple knows what they owe to open source software: https://opensource.apple.com/releases/

A lot of the core XNU and Darwin code is open source: https://opensource.apple.com/releases/

> When I'm seeing a weird network issue, I want to be able to peer into the kernel's tcp stack.

Uhh...

https://github.com/apple-oss-distributions/xnu/tree/xnu-8796...

I think NeXT might've written an HFS Standard reader or something, but they used the Apple code for HFS+ so it ended up as a hybrid.

https://github.com/apple-oss-distributions/xnu/blob/rel/xnu-...

Mach message passing and objc message passing have no relation. I don’t think xnu contains much if any objc.

Obviously not all of its, but they contribute quite a bit. https://opensource.apple.com/releases/

here is the kernel source (they have branches for each individual macos release with its darwin kernel ver, macos 13 is ver 8792.xx.x for instance): https://github.com/apple-oss-distributions/xnu

Apple does plenty of open source stuff. Safari's browser engine, Swift, libdispatch, the XNU kernel used by iOS and macOS, etc. And macOS is generally packed with open source things, like the default shell, zsh. Also, Metal actually predates Vulkan, so Vulkan was definitely not established when they started focusing on Metal. Yeah, they probably should consider supporting Vulkan now, but it's nothing to do with open source. The main beneficiaries of Apple supporting Vulkan would be people porting closed-source games.