Unions within unions

Question

In C, is it possible to define a union within another union? If no, why is it not possible? Or if yes, where can it be used?

Answer 1

Yes, a union may contain another union:

union foo {
  int x;
  double y;
  union bar {
    char blah[10];
    char *blurga;
  } bletch;
};

I can't think of a situation where it would be useful (or even desirable), though.