Re: epoll exposure

[nia <nia%NetBSD.org@localhost>]

On Mon, Aug 14, 2023 at 07:39:11AM -0400, Greg Troxel wrote:
> Jonathan Perkin <jperkin%pkgsrc.org@localhost> writes:
> 
> > * On 2023-08-13 at 18:10 BST, Tobias Nygren wrote:
> >
> >>On Sat, 12 Aug 2023 19:21:06 -0400
> >>Christos Zoulas <christos%zoulas.com@localhost> wrote:
> >>
> >>> I really want to understand what's going on here (why do we think that
> >>> our epoll implementation is broken in a way that will affect applications).
> >>
> >>jperkin@ might be able to explain what the issues with Illumos are,
> >>but I guess the problems are of different nature than the NetBSD case.
> >
> > The problem is third-party software assumes epoll == Linux, and once
> 
> I see it that Linux was first with epoll and thus is the specification.
> In an ideal world, it would have gone through POSIX, but whatever.
> Once that exists, I think an epoll implementation in other operating
> systems has to have the exact same semantics, or it's asking for
> trouble, perhaps hard-to-find ways.
> 
> I don't really find it problematic that the world has assigned the word
> epoll to Linux's implementation.  To object to that one has to object to
> any non-POSIX feature in any OS.

It's about assuming every other Linuxism is available if epoll is,
not exact semantics.