libmemcached Examples

Examples for libmemcached

DESCRIPTION

For full examples, test cases are found in tests/*.c in the main distribution. These are always up to date, and are used for each test run of the library.

Connecting to servers

const char *config_string =
  "--SERVER=host10.example.com "
  "--SERVER=host11.example.com "
  "--SERVER=host10.example.com";
memcached_st *memc= memcached(config_string, strlen(config_string));
{
  // ...
}
 memcached_free(memc);

In the above code you create a memcached_st object with three server by making use of memcached_create().

Creating a pool of servers

const char *config_string =
  "--SERVER=host10.example.com "
  "--SERVER=host11.example.com "
  "--SERVER=host10.example.com";

memcached_pool_st* pool= memcached_pool(config_string, strlen(config_string));

memcached_return_t rc;

memcached_st *memc= memcached_pool_pop(pool, false, &rc);

// .... do work

/*
  Release the memc_ptr that was pulled from the pool
*/
memcached_pool_push(pool, memc);

/*
  Destroy the pool.
*/
memcached_pool_destroy(pool);

In the above code you create a memcached_pool_st object with three server by making use of memcached_pool().

When memcached_pool_destroy() all memory will be released that is associated with the pool.

Adding a value to the server

char *key= "foo";
char *value= "value";
time_t expires = 0;
uint32_t flags = 0;

memcached_return_t rc = memcached_set(memc,
                                     key, strlen(key),
                                     value, value_length,
                                     expires, flags);

if (rc != MEMCACHED_SUCCESS)
{
    // handle failure
}

It is best practice to always look at the return value of any operation.

Fetching multiple values

memcached_return_t rc;
char *keys[]= {"fudge", "son", "food"};
size_t key_length[]= {5, 3, 4};
unsigned int x;
uint32_t flags;

char return_key[MEMCACHED_MAX_KEY];
size_t return_key_length;
char *return_value;
size_t return_value_length;

rc= memcached_mget(memc, keys, key_length, 3);

x= 0;
while ((return_value= memcached_fetch(memc, return_key, &return_key_length,
                                 &return_value_length, &flags, &rc)))
{
    free(return_value);
    x++;
}

Notice that you freed values returned from memcached_fetch(). The define MEMCACHED_MAX_KEY is provided for usage.

SEE ALSO

memcached(1)