#include <iostream>
#include <string>

struct S{
 int a;
 int b;
};



int main()
{
  S from;
  from.a = 10;
  from.b = 20;

  // to bytes
  char* s_bytes = reinterpret_cast<char*>(&from);

  // from bytes
  S *to;
  to = reinterpret_cast<S*>(s_bytes);
}