Darwin kqueue

[ioquatix]

No description provided.

[ioquatix]

@tarcieri Running the sample code from https://daniel.haxx.se/blog/2016/10/11/poll-on-mac-10-12-is-broken/ seems to indicate that at least poll is working on 10.14 - and I've enabled this in the PR and run the entire async-* test suite and it all seems to pass. On 10.14.5.

Given that nio4r breaking on macOS isn't probably going to destroy any production environments, maybe this is an acceptable change. What do you think?

[ioquatix]

[2] pry(main)> NIO::Selector.new.backend
=> :poll

Need to make it use kqueue by default.

[tarcieri]

@ioquatix I know poll(2) seemed to be working for awhile then regressed on macOS 10.12 so the platform is not exactly known for getting these sorts of APIs right, especially compared to the implementations on e.g. FreeBSD (which also had plenty of their own brokenness at first but eventually got better).

Otherwise, I’d say check if there have been any upstream libev changes around this if you haven’t already.

[ioquatix]

I recently updated nio4r to the latest libev release. I also checked the example source code from the blog post you linked to and it seems to pass at least on macOS 14.x - and according to those sources it was fixed on 10.12.2

I'll do some more investigations, but I think it should be safe (ish). As you state, macOS has a pretty shitty track record, so good to be cautious, but I think I have a pretty big test suite now, testing lots of fairly real-world situations.

[ioquatix]

I decided to be a bit more conservative and only enable it for 10.14+ because that's what I can test easily.

[ioquatix]

I've merged it by hand.