lsr: ls with io_uring

I am curious what would happen if ls and other commands were replaced using io_uring and kernel.io_uring_disabled was set to 1. Would it fall back to an older behavior or would the ability to disable it be removed?

You would have to write your IO to have a fallback. The Ghostty project uses `io_uring`, but on kernels where it isn't available it falls back to an `epoll` model. That's all handled at the library level by libxev.

I just realized that one could probably write a userspace io_uring emulator in a library that spawns a thread to read the ringbuffer and a worker pool of threads to do the blocking operations. You'd need to get the main software to make calls to your library instead of the io_uring syscalls, that's it; the app logic could remain the same.

Then all the software wanting to use io_uring wouldn't need to write their low-level things twice.

I'm about to start something like this targetting epoll, poll, dispatch_io and maybe kqueue this weekend.