Class kevent

src/bthread/fd.cpp:185–185

                      closing_epoll_pipe[1], &evt) < 0) {
#elif defined(OS_MACOSX)
        struct kevent kqueue_event;
        EV_SET(&kqueue_event, closing_epoll_pipe[1], EVFILT_WRITE, EV_ADD | EV_ENABLE,
                0, 0, NULL);
        if (kevent(saved_epfd, &kqueue_event, 1, NULL, 0, NULL) < 0) {