Struct casting example with IP address (little-endian)

gistfile1.txt

#include <stdio.h>
#include <stdint.h>

struct ip4 {
    uint8_t first;
    uint8_t second;
    uint8_t third;
    uint8_t fourth;
};

int main() {
    uint32_t whole_ip = -2; // IP address 255.255.255.254
    struct ip4* split_ip = (struct ip4*)(&whole_ip);
    printf("%d.%d.%d.%d\n", split_ip->fourth, split_ip->third, split_ip->second, split_ip->first);
    return 0;
}