double app_tminterval(int stop,int usertime)
	{
	double		ret=0;
	static clock_t	tmstart;
	static int	warning=1;

	if (usertime && warning)
		{
		BIO_printf(bio_err,"To get meaningful results, run "
				   "this program on idle system.\n");
		warning=0;
		}

	if (stop==TM_START)	tmstart = clock();
	else			ret     = (clock()-tmstart)/(double)CLOCKS_PER_SEC;

	return (ret);
	}
double app_tminterval(int stop,int usertime)
	{
	double		ret=0;
	static clock_t	tmstart;
	static int	warning=1;

	if (usertime && warning)
		{
		BIO_printf(bio_err,"To get meaningful results, run "
				   "this program on idle system.\n");
		warning=0;
		}

	if (stop==TM_START)	tmstart = clock();
	else			ret     = (clock()-tmstart)/(double)CLOCKS_PER_SEC;

	return (ret);
	}