Anonymous union and a normal union

Question

Can anybody please mention the differences between a normal and an anonymous union(or struct)? I have just found one:
functions can't be defined in anonymous union.

Answer 1

You don't require dot operator "." to access anonymous union elements.

#include <iostream> 
using namespace std;
int main() {
   union {
      int d;
      char *f;
   };

   d = 4;
   cout << d << endl;

   f = "inside of union";
   cout << f << endl;
}

This will successfully compile in this case but "NO" for normal Union.

Also, Anonymous union can only have public members.

PS :Simply omitting the class-name portion of the syntax does not make a union an anonymous union. For a union to qualify as an anonymous union, the declaration must not declare an object.