git.m6w6.name Git - awesomized/libmemcached/blob - docs/libmemcached_examples.rst

   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 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    memcached_server_st *servers;
  44    memcached_st *memc= memcached_create(NULL);
  45    char servername[]= "0.example.com";
  46
  47    servers= memcached_server_list_append(NULL, servername, 400, &rc);
  48
  49    for (x= 0; x < 20; x++)
  50    {
  51      char buffer[SMALL_STRING_LEN];
  52
  53      snprintf(buffer, SMALL_STRING_LEN, "%u.example.com", 400+x);
  54      servers= memcached_server_list_append(servers, buffer, 401, &rc);
  55    }
  56    rc= memcached_server_push(memc, servers);
  57    memcached_server_free(servers);
  58    memcached_free(memc);
  59
  60
  61 In the above code you create a \ ``memcached_st``\  object that you then feed in a
  62 single host into. In the for loop you build a \ ``memcached_server_st``\
  63 pointer that you then later feed via memcached_server_push() into the
  64 \ ``memcached_st``\  structure.
  65
  66 You can reuse the \ ``memcached_server_st``\  object with multile \ ``memcached_st``\
  67 structures.
  68
  69
  70 ----------------------------
  71 Adding a value to the server
  72 ----------------------------
  73
  74
  75
  76 .. code-block:: c
  77
  78    char *key= "foo";
  79    char *value;
  80    size_t value_length= 8191;
  81    unsigned int x;
  82
  83    value = (char*)malloc(value_length);
  84    assert(value);
  85
  86    for (x= 0; x < value_length; x++)
  87    value[x] = (char) (x % 127);
  88
  89    for (x= 0; x < 1; x++)
  90    {
  91      rc= memcached_set(memc, key, strlen(key),
  92      value, value_length,
  93      (time_t)0, (uint32_t)0);
  94      assert(rc == MEMCACHED_SUCCESS);
  95    }
  96
  97    free(value);
  98
  99
 100 It is best practice to always look at the return value of any operation.
 101
 102
 103 ------------------------
 104 Fetching multiple values
 105 ------------------------
 106
 107
 108
 109 .. code-block:: c
 110
 111    memcached_return_t rc;
 112    char *keys[]= {"fudge", "son", "food"};
 113    size_t key_length[]= {5, 3, 4};
 114    unsigned int x;
 115    uint32_t flags;
 116
 117    char return_key[MEMCACHED_MAX_KEY];
 118    size_t return_key_length;
 119    char *return_value;
 120    size_t return_value_length;
 121
 122    rc= memcached_mget(memc, keys, key_length, 3);
 123
 124    x= 0;
 125    while ((return_value= memcached_fetch(memc, return_key, &return_key_length,
 126                                          &return_value_length, &flags, &rc)))
 127    {
 128      free(return_value);
 129      x++;
 130    }
 131
 132
 133 Notice that you freed values returned from memcached_fetch(). The define
 134 \ ``MEMCACHED_MAX_KEY``\  is provided for usage.
 135
 136
 137
 138 ----
 139 HOME
 140 ----
 141
 142
 143 To find out more information please check:
 144 `https://launchpad.net/libmemcached <https://launchpad.net/libmemcached>`_
 145
 146
 147 --------
 148 SEE ALSO
 149 --------
 150
 151
 152 :manpage:`memcached(1)`
 153