Re: kevent ext member?

[Taylor R Campbell <campbell+netbsd-tech-kern%mumble.net@localhost>]

> Date: Wed, 9 Aug 2023 13:11:13 -0400
> From: Theodore Preduta <theo%pta.gg@localhost>
> 
> On 2023-08-09 04:58, Taylor R Campbell wrote:
> >> Date: Tue, 8 Aug 2023 11:47:17 -0400
> >> From: Theodore Preduta <theo%pta.gg@localhost>
> >>
> >> The semantics come from MacOS (and are the same in FreeBSD).
> > 
> > OK, thanks!  What do they use it for?
> 
> MacOS uses it for their EVFILT_MACHPORT (which is EVFILT_READ but for
> MacOS's IPC primitive) to return a pointer to the received message,
> which I doubt can be ported.
> 
> I don't think that FreeBSD currently makes use of it outside of Linux
> epoll compat.

Cool, thanks!  Seems like kind of poor API design but not one we have
much control over if we want kqueue to remain compatible with FreeBSD
and macOS, which is generally good.