[pjmlp]

Except contrary to urban myths that isn't exclusive to UNIX and precedes it.

[monocasa]

I never said that was exclusive to unix likes, only that it being a microkernel doesn't preclude it from being a unix like.

[pjmlp]

"kernel provided abstraction is very "unix style" reads otherwise.

[monocasa]

Providing _a posix filesystem_ as a kernel abstraction is what I said. Which is not very standard for microkernels, and makes it (redox) pretty unix like at the kernel level.

The overall point being that both, microkernels can be unix likes, and redox particularly and at the kernel level leans in to being a unix like.

[pjmlp]

IBM and Unisys mainframes also support POSIX filesystems, as does Windows, so now they are UNIXes?

[monocasa]

z/OS is a full blown, certified UNIX. WSL1 makes NT a unix kernel if they wanted to get the certification.

And redox goes beyond them in that the only user mode env it supports is posix with some extensions.

But how is this line germane to the original point again? That somehow being a microkernel means that it can't be a unix like design OS?

[pjmlp]

Certified UNIX means having a userspace POSIX library, completely unrelated to kernel architectures.

So if Microsoft bothers to certify WSL2 then Windows is now UNIX?!?