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

int alarm_seen = 0, user1_seen = 0;
void alarm_handler( int sig)
{
    alarm_seen = 1;
}
void user1_handler( int sig)
{
    user1_seen = 1;
}

main(int argc, char * argv[])
{
  int count = 0, idle = 0, period = 10;

  signal(SIGALRM, alarm_handler);
  signal(SIGUSR1, user1_handler);

  alarm(period);
  while (!alarm_seen) {
    count++;
    kill(getpid(), SIGUSR1);
    while (!user1_seen) {idle++;}
    user1_seen = 0;
  }
  printf("Handled %d signals in %d seconds, idle %d\n", count, period, idle);
}