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   1 =====================
   2 libmemcached examples
   3 =====================
   4
   5
   6 Examples for libmemcached
   7
   8
   9 -----------
  10 DESCRIPTION
  11 -----------
  12
  13
  14 For full examples, test cases are found in tests/\*.c in the main
  15 distribution. These are always up to date, and are used for each test run of
  16 the library.
  17
  18 ------------------------------
  19 Creating and Freeing structure
  20 ------------------------------
  21
  22
  23 .. code-block:: perl
  24
  25    memcached_st *memc;
  26    memcached_return_t rc;
  27
  28    memc= memcached_create(NULL);
  29    ...do stuff...
  30    memcached_free(memc);
  31
  32
  33 The above code would create a connection and then free the connection when
  34 finished.
  35
  36
  37 ---------------------
  38 Connecting to servers
  39 ---------------------
  40
  41
  42
  43 .. code-block:: perl
  44
  45    memcached_server_st *servers;
  46    memcached_st *memc= memcached_create(NULL);
  47    char servername[]= "0.example.com";
  48
  49    servers= memcached_server_list_append(NULL, servername, 400, &rc);
  50
  51    for (x= 0; x < 20; x++)
  52    {
  53      char buffer[SMALL_STRING_LEN];
  54
  55      snprintf(buffer, SMALL_STRING_LEN, "%u.example.com", 400+x);
  56      servers= memcached_server_list_append(servers, buffer, 401, &rc);
  57    }
  58    rc= memcached_server_push(memc, servers);
  59    memcached_server_free(servers);
  60    memcached_free(memc);
  61
  62
  63 In the above code you create a \ ``memcached_st``\  object that you then feed in a
  64 single host into. In the for loop you build a \ ``memcached_server_st``\
  65 pointer that you then later feed via memcached_server_push() into the
  66 \ ``memcached_st``\  structure.
  67
  68 You can reuse the \ ``memcached_server_st``\  object with multile \ ``memcached_st``\
  69 structures.
  70
  71
  72 ----------------------------
  73 Adding a value to the server
  74 ----------------------------
  75
  76
  77
  78 .. code-block:: perl
  79
  80    char *key= "foo";
  81    char *value;
  82    size_t value_length= 8191;
  83    unsigned int x;
  84
  85    value = (char*)malloc(value_length);
  86    assert(value);
  87
  88    for (x= 0; x < value_length; x++)
  89    value[x] = (char) (x % 127);
  90
  91    for (x= 0; x < 1; x++)
  92    {
  93      rc= memcached_set(memc, key, strlen(key),
  94      value, value_length,
  95      (time_t)0, (uint32_t)0);
  96      assert(rc == MEMCACHED_SUCCESS);
  97    }
  98
  99    free(value);
 100
 101
 102 It is best practice to always look at the return value of any operation.
 103
 104
 105 ------------------------
 106 Fetching multiple values
 107 ------------------------
 108
 109
 110
 111 .. code-block:: perl
 112
 113    memcached_return_t rc;
 114    char *keys[]= {"fudge", "son", "food"};
 115    size_t key_length[]= {5, 3, 4};
 116    unsigned int x;
 117    uint32_t flags;
 118
 119    char return_key[MEMCACHED_MAX_KEY];
 120    size_t return_key_length;
 121    char *return_value;
 122    size_t return_value_length;
 123
 124    rc= memcached_mget(memc, keys, key_length, 3);
 125
 126    x= 0;
 127    while ((return_value= memcached_fetch(memc, return_key, &return_key_length,
 128                                          &return_value_length, &flags, &rc)))
 129    {
 130      free(return_value);
 131      x++;
 132    }
 133
 134
 135 Notice that you freed values returned from memcached_fetch(). The define
 136 \ ``MEMCACHED_MAX_KEY``\  is provided for usage.
 137
 138
 139
 140 ----
 141 HOME
 142 ----
 143
 144
 145 To find out more information please check:
 146 `https://launchpad.net/libmemcached <https://launchpad.net/libmemcached>`_
 147
 148
 149 --------
 150 SEE ALSO
 151 --------
 152
 153
 154 :manpage:`memcached(1)`
 155