FYI, Apple platforms have had futexes since iOS 17.4 and macOS 14.4: https://developer.apple.com/documentation/os/synchronization?language=objc https://develope

FYI, Apple platforms have had futexes since iOS 17.4 and macOS 14.4: https://developer.apple.com/documentation/os/synchronization?language=objc https://developer.apple.com/documentation/os/synchronization... Unfortunately, you sacrifice the priority inversion avoidance you would otherwise get with os_unfair_lock.