int main(int argc, char *argv[]) {
struct sigaction sa;
sigset_t blockingMask, prevMask, emptyMask;
printf("%s: PID: %d\n", argv[0], getpid());
sigemptyset(&emptyMask);
sigemptyset(&blockingMask);
sigaddset(&blockingMask, SIGALRM);
if (sigprocmask(SIG_SETMASK, &blockingMask, &prevMask) == -1)
errExit("sigprocmask error");
sa.sa_handler = sigHandler;
sigemptyset(&sa.sa_mask);
sa.sa_flags = 0;
if (sigaction(SIGALRM, &sa, NULL) == -1)
errExit("sigaction error");
my_alarm(1);
for (;;) {
if (sigsuspend(&emptyMask) == -1 && errno != EINTR)
errExit("sigsuspend issue");
}
if (sigprocmask(SIG_SETMASK, &prevMask, NULL) == -1)
errExit("sigprocmask error");
exit(EXIT_SUCCESS);
}
int
main(int argc, char *argv[]){
sigset_t mask;
sigemptyset(&mask);
sigaddset(&mask,SIGALRM); //block SIGALRM so it doesn't term proc
if(sigprocmask(SIG_SETMASK,&mask,NULL)!=0)
exit(EXIT_FAILURE);
my_alarm(5); //wait 5 seconds
siginfo_t info; //wait synchronously for SIGALRM
sigwaitinfo(&mask,&info);
if(info.si_signo == SIGALRM) //check signo
printf("ALARMED!\n");
exit(EXIT_SUCCESS);
}
