illumos gate

Currently:

       The list_next() and list_prev() functions return the next or previous
       item in the list, relative to the named reference item which must be
       linked on the list.

It says nothing about returning NULL when reaching one or the other end of the list. Perhaps something like:

       The list_next() and list_prev() functions return the next or previous
       item in the list, relative to the named reference item which must be
       linked on the list. If the named reference item is at the end (for list_next())
       or beginning (for list_prev()) of the list, the function returns NULL.