#include <stdio.h>

template <typename T>
T swap_endian(T u)
{
    static_assert (CHAR_BIT == 8, "CHAR_BIT != 8");

    union
    {
        T u;
        unsigned char u8[sizeof(T)];
    } source, dest;

    source.u = u;

    for (T k = 0; k < sizeof(T); k++)
        dest.u8[k] = source.u8[sizeof(T) - k - 1];

    return dest.u;
}

int main(){
        int le = 0x00FF3200, be;
        be=swap_endian<int>(le);
        printf("LE: 0x%08x\nBE: 0x%08x\n", le, be);
        return 0;
}