memcached_return_t rc;
char *out_value= memcached_get(memc, keys.key_at(which_key), keys.length_at(which_key),
&value_length, &flags, &rc);
memcached_return_t rc;
char *out_value= memcached_get(memc, keys.key_at(which_key), keys.length_at(which_key),
&value_length, &flags, &rc);