#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main(int argc, char *argv[]) {
  char buf[255];
  int s;
  FILE *f;
  pid_t pid;
  switch((pid = fork())) {
    case 0:
      sprintf(buf, "gdb %s %i", argv[0], getppid());
      f = popen(buf, "w");
      fprintf(f, "bt\n");
      fprintf(f, "quit\n");
      fflush(f);
      wait(&s);
      pclose(f);
      break;
    case -1:
      return 1;
    default:
      waitpid(pid, &s, 0);
  }
  return 0;
}