the data structure -- doubly linked chains:

[Bert]

(1)what is the order of nodes in the chains?
it is like the head, the first, the second, ..., 
the last, the tail or the head is also the first
and the tail is also the last?

(2)the function:

RTEMS_INLINE_ROUTINE Chain_Node *_Chain_Tail(
Chain_Control *the_chain 
)
{
  return (Chain_Node *) &the_chain->permanent_null;
}

is it necessary to use the operator "&" ?

is it right to implement the function as follows:

RTEMS_INLINE_ROUTINE Chain_Node *_Chain_Tail(
Chain_Control *the_chain 
)
{
  return (Chain_Node *) (the_chain->last)->next;
}

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