libmemcached Examples — libmemcached-awesome 1.1.3 documentation

# 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)