Listing 2.  Same as listing 1, but with sigaction.


#include <signal.h>
#include <stdio.h>

void my_handler (int sig); /* function prototype */

int main ( void ) {

    struct sigaction my_action;

/* Part I: Catch SIGINT */

    my_action.sa_handler = my_handler;
    my_action.sa_flags = SA_RESTART;
    sigaction (SIGINT, &my_action, NULL);
    printf ("Catching SIGINT\n");
    sleep(3);
    printf (" No SIGINT within 3 seconds\n");


/* Part II: Ignore SIGINT */

   my_action.sa_handler = SIG_IGN;
   my_action.sa_flags = SA_RESTART;
   sigaction (SIGINT, &my_action, NULL);
   printf ("Ignoring SIGINT\n");
   sleep(3);
   printf (" Sleep is over\n");


/* Part III: Default action for  SIGINT */

  my_action.sa_handler = SIG_DFL;
  my_action.sa_flags = SA_RESTART;
  sigaction (SIGINT, &my_action, NULL);
  sleep(3);
  printf ("No SIGINT within 3 seconds\n");
}

void my_handler (int sig) {
    printf ("I got SIGINT, number %d\n", sig);
    exit(0);
}