HS>   I thought I could just do a simple cast to the
HS>   structure + 1 (the extra byte is where the TYPE lies)
   You don't need the +1.
typedef struct { char type, name[16]; long stats[16]; } PERSON;
typedef struct { char type, label[16]; float status; } OBJECT;
void ShowStatus(void *Obj)
/*   Show object status or person hit points   */
{
   switch(*((char*)Obj))
   {
      case 'p':
         printf("Hit Points: %dl", ((PERSON*)Obj)->stats[0]);
         break;
      case 'o':
         printf("Status: %f", ((OBJECT*)Obj)->status);
         break;
      default: break;
   }
}
   Your structure, as defined, takes the extra char into account
   already, and relies on its being there when calculating the
   other members' positions within the data block and values.

> ] Happiness is a Porsche. LUNCH is a warm puppy...............

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