+/* Structure for holding time-limited data such as DNS returns.
+We use this rather than extending tree_node to avoid wasting
+space for most tree use (variables...) at the cost of complexity
+for the lookups cache */
+
+typedef struct expiring_data {
+ time_t expiry; /* if nonzero, data invalid after this time */
+ void *ptr; /* pointer to data */
+} expiring_data;
+