Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.Prune svn:mergeinfo from the new branch, as nothing has been mergedhere.Additional commits post-branch will follow.Approved by: re (implicit)Sponsored by: The FreeBSD Foundation
Add missing header needed by sleep(3).
initialize mutex and cv.
Fix spelling.
Add a test for pthread's cv and cancellation.