-bool procedure (bool (*proc_func) (struct ccase *, void *aux), void *aux);
-bool procedure_with_splits (void (*begin_func) (void *aux),
- bool (*proc_func) (struct ccase *, void *aux),
- void (*end_func) (void *aux),
+bool procedure (bool (*proc_func) (struct ccase *, void *),
+ void *aux);
+bool procedure_with_splits (void (*begin_func) (const struct ccase *, void *),
+ bool (*proc_func) (const struct ccase *, void *),
+ void (*end_func) (void *),