How to use sigsuspend

Question

I have this code, and i have to make the program block repeatedly waiting for a signal. My teacher wants us to use the sigsuspend and masks instead of pause or sleep. I\'m not f

Answer 1

The simple way to get started is to just call sigsuspend with an empty mask (i.e., any signal can wake up the program):

sigset_t myset;
(void) sigemptyset(&myset);
while (1) {
    (void) printf("I'm running, waiting for a signal...\n");
    (void) sigsuspend(&myset);
}

The next step would be to use sigprocmask to disable your two handled signals (SIGINT and SIGQUIT) from occurring other than when you're waiting from them in sigsuspend. Then you would use the “old mask” obtained from sigprocmask instead of the empty mask when suspending.