float.c

/* Example code for Think OS.

Copyright 2014 Allen Downey
License: GNU GPLv3

*/

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


int main ()
{
    union {
        float f;
        unsigned int u;
    } p;

    p.f = -13.0;
    unsigned int sign = (p.u >> 31) & 1;
    unsigned int exp = (p.u >> 23) & 0xff;

    unsigned int coef_mask = (1 << 23) - 1;
    unsigned int coef = p.u & coef_mask;

    printf("%d\n", sign);
    printf("%d\n", exp);
    printf("0x%x\n", coef);
    
    return 0;
}