int ewah_serialize_native(struct ewah_bitmap *self, int fd);
int ewah_serialize_strbuf(struct ewah_bitmap *self, struct strbuf *);
-int ewah_deserialize(struct ewah_bitmap *self, int fd);
ssize_t ewah_read_mmap(struct ewah_bitmap *self, const void *map, size_t len);
uint32_t ewah_checksum(struct ewah_bitmap *self);