illumos gate

#include <float.h>

#include <fenv.h>

#include <stdio.h>

#include <strings.h>

int main(void)

{

	const int size=100;

	int status, i, j, precision;

	char buffer[size], check[size];

	double val;

	fesetround(FE_TONEAREST);

	for (j=1; j<100; j++) 

	{

	for (i=2; i<100; i++)

	{

#ifndef __DBL_DECIMAL_DIG__

		for (precision = DBL_DIG-1; precision <= DECIMAL_DIG; precision++)

#else

		for (precision = DBL_DIG-1; precision <= __DBL_DECIMAL_DIG__; precision++)

#endif

		{

			val = (double)(0.0 + j) / i;

			// first get max precision for control check

			status = snprintf(check, size, "%+-.*f", DECIMAL_DIG, val);

   			if (status <0)

				return status;

			// then get specific precision

			status = snprintf(buffer,size,"%+-#.*f",precision,val);

   			if (status <0)

				return status;

			if (strlen(check)>strlen(buffer) && 

					strncmp(buffer, check, strlen(buffer)))

			{	//last check if correctly rounded up 

				if (check[strlen(buffer)] < '5' && 

					buffer[strlen(buffer)-1]> check[strlen(buffer)-1])

	   					printf("failure:f precision %d for %02d/%02d => %s (%s)\n",

							precision, j, i, buffer, check);

			}

		}

	}

	}

	return 0;

}