memcached_execute_function callbacks[1]= { [0]= &callback_counter };
rc= memcached_mget_execute(memc, (const char**)keys, key_length,
(size_t)max_keys, callbacks, &counter, 1);
memcached_execute_function callbacks[1]= { [0]= &callback_counter };
rc= memcached_mget_execute(memc, (const char**)keys, key_length,
(size_t)max_keys, callbacks, &counter, 1);