// display the data in a circular linked list;
// List points to its last node
if (List != NULL)
{  // list is not empty
   ptrType First = List->Next; // point to first node

   ptrType Cur = First;        // start at first node
   // Loop invariant: Cur points to next node to 
   // display
   do
   {  Display(Cur->Item);      // write data portion
      Cur = Cur->Next;         // point to next node 
   } while (Cur != First);     // list traversed?
}  // end if