+/**
+ * Iterate over all elements in the given set.
+ * Note that this operation involves transferring every element of the set
+ * from the service to the client, and is thus costly.
+ * Only one iteration per set may be active at the same time.
+ *
+ * @param set the set to iterate over
+ * @param iter the iterator to call for each element
+ * @param iter_cls closure for @a iter
+ * @return #GNUNET_YES if the iteration started successfuly,
+ * #GNUNET_NO if another iteration was still active,
+ * #GNUNET_SYSERR if the set is invalid (e.g. the server crashed, disconnected)
+ */
+int
+GNUNET_SET_iterate (struct GNUNET_SET_Handle *set,
+ GNUNET_SET_ElementIterator iter,
+ void *iter_cls);
+
+
+/**
+ * Stop iteration over all elements in the given set. Can only
+ * be called before the iteration has "naturally" completed its
+ * turn.
+ *
+ * @param set the set to stop iterating over
+ */
+void
+GNUNET_SET_iterate_cancel (struct GNUNET_SET_Handle *set);
+
+
+/**
+ * Create a copy of an element. The copy
+ * must be GNUNET_free-d by the caller.
+ *
+ * @param element the element to copy
+ * @return the copied element
+ */
+struct GNUNET_SET_Element *
+GNUNET_SET_element_dup (const struct GNUNET_SET_Element *element);
+
+
+/**
+ * Hash a set element.
+ *
+ * @param element the element that should be hashed
+ * @param ret_hash a pointer to where the hash of @a element
+ * should be stored
+ */
+void
+GNUNET_SET_element_hash (const struct GNUNET_SET_Element *element,
+ struct GNUNET_HashCode *ret_hash);
+
+