how to choose struct's endianness cpp
#include <stdio.h>
#include <stdint.h>
//The line bellow does the trick:
//__attribute__((packed, scalar_storage_order("big-endian")))
struct __attribute__((packed, scalar_storage_order("big-endian"))) mystruct {
uint16_t a;
uint32_t b;
uint64_t c;
};
int main(int argc, char** argv) {
struct mystruct bar = {.a = 0xaabb, .b = 0xff0000aa, .c = 0xabcdefaabbccddee};
FILE *f = fopen("out.bin", "wb");
size_t written = fwrite(&bar, sizeof(struct mystruct), 1, f);
fclose(f);
}