#include <signal.h>
#include <unistd.h>
#include <linux/unistd.h>
#include <stdlib.h>
#include <sched.h>
#include <stdio.h>
#include <time.h>

volatile int dummy;
volatile int child_run = 1;

/* #define DPRINTF(a...) fprintf(stderr, a) */
#define DPRINTF(a...) do { } while (0)

void child_signal_handler (int signum)
{
  child_run = 0;
}

int main (void)
{
  int child;
  struct timespec tp = { 5, 0 };
  struct sched_param param;
  param.sched_priority = 5;
  sched_setscheduler (0, SCHED_FIFO, &param);
  child = fork();
  switch (child)
  {
   case 0:
    DPRINTF("Child starts\n");
    signal (SIGTERM, child_signal_handler);
    param.sched_priority = 4;
    sched_setscheduler (0, SCHED_FIFO, &param);
    for (; child_run;)
      dummy = dummy + 1;
    DPRINTF("Child dies\n");
    break;
   case -1:
    perror ("fork failed");
    abort();
    break;    
   default:
/*     sleep (5); */
    syscall (__NR_nanosleep, &tp, NULL);
    kill (child, SIGTERM);
   break;
  }
  return 0;
}