Ifacepos ()

   Synopsis:
      Returns the position of the current interface notification

   Notes:
      The interface notification list contains all the notifications received,
         and not yet processed, as the result of an earlier SETTRIG, SETALIAS,
         SETMACRO, SETTIMER or SETHOOK statement.
      The first notification in the list is at position 1 in the list, the
         second at position 2, and so on.
      If the list is empty, 0 is returned.
