sigprocmask (2), sigqueue (3), sigsetops (3), sigwait (3), timespec (3), signal (7), timesigprocmask (2), sigqueue (3), sigsetops (3), sigwait (3), timespec (3), signal (7), timesigprocmask (2), sigqueue (3), sigsetops (3), sigwait (3), timespec (3), signal (7), timesigprocmask (2), sigwaitinfo (2), sigsetops (3), sigwait (3), signalsigwaitinfo (2), timerfd_create (2), sigsetops (3), sigwait (3), epoll (7), signalsigwaitinfo (2), timerfd_create (2), sigsetops (3), sigwait (3), epoll (7), signalunblocked or is waiting for it in sigwait (3), at least one unblocked signal must