const char *master_key, size_t master_key_length,
const char *key, size_t key_length,
uint64_t offset,
uint64_t *value);
LIBMEMCACHED_API
const char *master_key, size_t master_key_length,
const char *key, size_t key_length,
uint64_t offset,
uint64_t *value);
LIBMEMCACHED_API