Go
16 Sep 2026
4 min read
Go sync.Cond Wait Rechecks Shared State
sync.Cond.Wait resumes after a notification, but the notification does not assert that a caller-specific condition is still true when the goroutine reacquires the lock. The shared predicate remains the source of truth, so a waiter checks it again after every return from Wait. This boundary separates notification from state. Signal and Broadcast announce that relevant state may have changed; they do not transfer ownership of that state or reserve it for a particular waiter.