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

#include <sys/types.h>
#include <sys/wait.h>

volatile unsigned long loop = 10000000;

void
handler (int n)
{
  if (loop > 0)
    --loop;
}

static int
child (void)
{
  pid_t ppid = getppid ();

  sleep (1);
  while (1)
    kill (ppid, SIGUSR1);
  return 0;
}

int
main (int argc, char **argv)
{
  pid_t child_pid;
  int r;

  loop = argc > 1 ? strtoul (argv[1], NULL, 10) : 10000000;
  printf ("expecting to receive %lu signals\n", loop);

  if ((child_pid = fork ()) == 0)
    exit (child ());

  signal (SIGUSR1, handler);
  while (loop)
    sleep (1);
  r = kill (child_pid, SIGTERM);
  waitpid (child_pid, NULL, 0);
  return 0;
}