…which is still limited compared to IOCP. I’d love to be able to wait for locks, semaphores, etc. using uring. But no, even if you fall back to POSIX semaphores, the “everything is a file” paradigm has far too many asterisks to deliver on its promise.

Pop quiz: across all kinds of FDs (including block files, dirfds, sockets, signalfds, eventfds, lock descriptors, /proc files, tmpfs files, timerfds, and so on), which features of {select/epoll, io_uring, O_NOBLOCK, inotify/fanotify, etc.} are supported?