+
+/**
+ * \brief Get or create an IPv6 fib.
+ *
+ * Get or create an IPv6 fib with the provided fib ID or index.
+ * The fib ID is a possibly-sparse user-defined value while
+ * the fib index defines the position of the fib in the fib vector.
+ *
+ * \param im
+ * ip6_main pointer.
+ * \param table_index_or_id
+ * The table index if \c IP6_ROUTE_FLAG_FIB_INDEX bit is set in \p flags.
+ * Otherwise, when set to \c ~0, an arbitrary and unused fib ID is picked
+ * and can be retrieved with \c ret->table_id.
+ * Otherwise, it is the fib ID to be used to retrieve or create the desired fib.
+ * \param flags
+ * Indicates whether \p table_index_or_id is the fib index or ID.
+ * When the bit \c IP6_ROUTE_FLAG_FIB_INDEX is set, \p table_index_or_id
+ * is considered as the fib index, and the fib ID otherwise.
+ * \return A pointer to the retrieved or created fib.
+ *
+ * \remark When getting a fib with the fib index, the fib MUST already exist.
+ */