-memcached_return (*memcached_trigger_key)(memcached_st *ptr, char *key, size_t key_length, memcached_result_st *result);
+memcached_return_t (*memcached_trigger_key)(memcached_st *ptr, char *key, size_t key_length, memcached_result_st *result);
+
+=item MEMCACHED_CALLBACK_DELETE_TRIGGER
+
+This function implements a trigger upon successful deletion of a key. The memcached_st structure will need to be cloned
+in order to make use of it.
+
+The prototype for this is:
+typedef memcached_return_t (*memcached_trigger_delete_key)(memcached_st *ptr, char *key, size_t key_length);
+