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static void print_double(double d, size_t precision) 
{
	double di, df, pr, tmp;
   
	/* if it's zero, just print the '0' and exit */
	if(d == 0.0)
	{ print_char('0'); return; }
	/* if it's a negative integer, print '-' and make the integer absolute */
	else if (d < 0) 
	{
		print_char('-');
		d = fabs(d);
	}
   
	/* break the double into fraction (df) and integer (di) parts */
	df = modf(d, &di);

	/* print the integer portion */
	print_int((size_t)floor(di));

	/* round up if necessary */
	if (df != 0) 
	{ 
		print_char('.');

		pr = df * pow(10, precision+1);
		modf(pr, &pr);
		
		/* we need to extract the last+1 decimal place and see if we should round up */
		while(pr > 10.0){ pr /= 10; }
		/* if it's 4, we should check the next decimal place to see if it's >= 5 */
		if(pr == 4)
		{
			pr = df * pow(10, precision+2);
			modf(pr, &pr);
			while(pr > 10.0){ pr /= 10; }
			if(pr >= 5){ df = df + (0.1 / pow(10, precision)); }
		}
		if(pr >= 5){ df = df + (0.1 / pow(10, precision)); }
	}

	/* calculate the fractional portion to print */
	while (df != 0 && precision--) 
	{
		df = df * 10;
		df = modf(df, &di);

		print_int((int)di);
	}
}