__extern int sigprocmask(int, const sigset_t *, sigset_t *);
__extern int sigpending(sigset_t *);
__extern int sigsuspend(const sigset_t *);
-__extern int rt_sigaction(int, const struct sigaction *, struct sigaction *, size_t);
-__extern int rt_sigprocmask(int, const sigset_t *, sigset_t *, size_t);
-__extern int rt_sigpending(sigset_t *, size_t);
-__extern int rt_sigsuspend(const sigset_t *, size_t);
__extern int raise(int);
__extern int kill(pid_t, int);