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   1 ========
   2 Examples
   3 ========
   4
   5 Examples for libmemcached
   6
   7 -----------
   8 DESCRIPTION
   9 -----------
  10
  11
  12 For full examples, test cases are found in tests/\*.c in the main
  13 distribution. These are always up to date, and are used for each test run of
  14 the library.
  15
  16 -----------------------------------------------
  17 Creating and Freeing the memcached_st structure
  18 -----------------------------------------------
  19
  20
  21 .. code-block:: c
  22
  23    memcached_st *memc;
  24    memcached_return_t rc;
  25
  26    memc= memcached_create(NULL);
  27    ...do stuff...
  28    memcached_free(memc);
  29
  30
  31 The above code would create a connection and then free the connection when
  32 finished.
  33
  34
  35 ---------------------
  36 Connecting to servers
  37 ---------------------
  38
  39
  40
  41 .. code-block:: c
  42
  43    const char *config_string= "--SERVER=host10.example.com --SERVER=host11.example.com --SERVER=host10.example.com"
  44    memcached_st *memc= memcached_create_with_options(config_string, strlen(config_string);
  45    {
  46     ...
  47    }
  48    memcached_free(memc);
  49
  50
  51 In the above code you create a \ ``memcached_st``\  object with three server by making use of :manpage:`memcached_create_with_options(3)`.
  52
  53
  54 --------------------------
  55 Creating a pool of servers
  56 --------------------------
  57
  58
  59
  60 .. code-block:: c
  61
  62   const char *config_string= "--SERVER=host10.example.com --SERVER=host11.example.com --SERVER=host10.example.com";
  63
  64   memcached_pool_st* pool= memcached_pool(config_string, strlen(config_string));
  65
  66   memcached_return_t rc;
  67
  68   memcached_st *memc= memcached_pool_pop(pool, false, &rc);
  69
  70   .... do work
  71
  72   /*
  73     Release the memc_ptr that was pulled from the pool
  74   */
  75   memcached_pool_push(pool, memc);
  76
  77   /*
  78     Destroy the pool.
  79   */
  80   memcached_pool_destroy(pool);
  81
  82
  83
  84 In the above code you create a \ ``memcached_pool_st``\  object with three
  85 server by making use of :manpage:`memcached_pool(3)`.
  86
  87 When memcached_pool_destroy() all memory will be released that is associated
  88 with the pool.
  89
  90
  91 ----------------------------
  92 Adding a value to the server
  93 ----------------------------
  94
  95
  96
  97 .. code-block:: c
  98
  99    char *key= "foo";
 100    char *value;
 101    size_t value_length= 8191;
 102    unsigned int x;
 103
 104    value = (char*)malloc(value_length);
 105    assert(value);
 106
 107    for (x= 0; x < value_length; x++)
 108    value[x] = (char) (x % 127);
 109
 110    for (x= 0; x < 1; x++)
 111    {
 112      rc= memcached_set(memc, key, strlen(key),
 113      value, value_length,
 114      (time_t)0, (uint32_t)0);
 115      assert(rc == MEMCACHED_SUCCESS);
 116    }
 117
 118    free(value);
 119
 120
 121 It is best practice to always look at the return value of any operation.
 122
 123
 124 ------------------------
 125 Fetching multiple values
 126 ------------------------
 127
 128
 129
 130 .. code-block:: c
 131
 132    memcached_return_t rc;
 133    char *keys[]= {"fudge", "son", "food"};
 134    size_t key_length[]= {5, 3, 4};
 135    unsigned int x;
 136    uint32_t flags;
 137
 138    char return_key[MEMCACHED_MAX_KEY];
 139    size_t return_key_length;
 140    char *return_value;
 141    size_t return_value_length;
 142
 143    rc= memcached_mget(memc, keys, key_length, 3);
 144
 145    x= 0;
 146    while ((return_value= memcached_fetch(memc, return_key, &return_key_length,
 147                                          &return_value_length, &flags, &rc)))
 148    {
 149      free(return_value);
 150      x++;
 151    }
 152
 153
 154 Notice that you freed values returned from memcached_fetch(). The define
 155 \ ``MEMCACHED_MAX_KEY``\  is provided for usage.
 156
 157
 158
 159 ----
 160 HOME
 161 ----
 162
 163
 164 To find out more information please check:
 165 `https://launchpad.net/libmemcached <https://launchpad.net/libmemcached>`_
 166
 167
 168 --------
 169 SEE ALSO
 170 --------
 171
 172
 173 :manpage:`memcached(1)`
 174