C Determine endianess

I wrote it and i edited wikipedias article which had a terrible code and added mine, but i'm still not sure about my code, is it SCALABLE ENOUGH?

#include <stdio.h>

int main() {

        union {
                int s;
                char c[sizeof(int)];
        } un;
        const char *endianess[[] = { "big endian", "little endian" };

        un.s = (~(int)0) ^ (~(char)0);
        puts(endianess[!un.c[0]]);

        return 0;
}

It still doesn't make any sense to do it at runtime, since the machine isn't going to change its endianness depending on whether it's executing the compiler or your program.