c function that will count the number of bytes needed to store a value

bcount

/*
 * compile with:
 *   g++ -lm bcount.c -o bcount
 */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>

int main(int argc, char **argv) {
        long num = atol(argv[1]);
        long cnt = 0;
        long min = (num < 0) ? -1 : 0;
        
        while (num != min) {
                num >>= 1;
                cnt++;
        }
        
        printf("total bytes %lu\n", (long)ceil(cnt/8.0));

        return 0;
}