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

static volatile int yup = 1; 

static void __sig_handler(int signo)
{
  yup = 0;
}

int main(int argc, char *argv[])
{
  signal(SIGTRAP, __sig_handler);
  raise(SIGTRAP);

  printf("traced = %d\n", yup);

  return 0;
}