Demonstrating properties of hexadecimal floating-point literals

fphex.c

#include <stdlib.h>
#include <stdio.h>

int main(int argc, char *argv[]) {
	double one = 0x100p-8;
	printf("one: %f\n", one);
	printf("0x100p-8 == 0x1p+0: %d\n", 0x100p-8 == 0x1p+0);
	printf("0x100p-8 == 1.0: %d\n", 0x100p-8 == 1.0);

	double n = 0xe5p-8, d = 0xffp-8;
	printf("%f/%f = %f\n", n, d, n/d);

	return EXIT_SUCCESS;
}