#include <iostream>
#include <unistd.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <signal.h>

const int EX_RUNERR = 127;

int main(int argc, char* argv[]) {
  /* arguments */
  if (argc != 2) {
    std::cerr << "Usage: " << argv[0] << " WAIT_SECONDS" << std::endl;
    exit(EXIT_FAILURE);
  }
  int wait_time = atoi(argv[1]);

  /* fork */
  pid_t pid = fork();
  char* const program = const_cast<char*>("./forever");
  char* const program_argv[] = { NULL };

  /* parent */
  if (pid) {
    if (pid == -1) { exit(EXIT_FAILURE); }

    sleep(wait_time);
    if (kill(pid, SIGSTOP) == -1) { exit(EXIT_FAILURE); }

    sleep(wait_time);
    if (kill(pid, SIGCONT) == -1) { exit(EXIT_FAILURE); }

    sleep(wait_time);
    if (kill(pid, SIGKILL) == -1) { exit(EXIT_FAILURE); }

    waitpid(pid, NULL, 0);
  }
  /* child  */
  else {
    execv(program, program_argv);
    exit(EX_RUNERR);
  }
  exit(EXIT_SUCCESS);
}