git.m6w6.name Git - m6w6/libmemcached/blob - docs/memcached_auto.rst

   1 =========================================================
   2 Incrementing and Decrementing values stored in the server
   3 =========================================================
   4
   5
   6 Manipulate counters
   7
   8
   9 *******
  10 LIBRARY
  11 *******
  12
  13
  14 C Client Library for memcached (libmemcached, -lmemcached)
  15
  16
  17 --------
  18 SYNOPSIS
  19 --------
  20
  21
  22
  23 .. code-block:: perl
  24
  25    #include <libmemcached/memcached.h>
  26
  27    memcached_return_t
  28      memcached_increment (memcached_st *ptr,
  29                           const char *key, size_t key_length,
  30                           unsigned int offset,
  31                           uint64_t *value);
  32
  33    memcached_return_t
  34      memcached_decrement (memcached_st *ptr,
  35                           const char *key, size_t key_length,
  36                           unsigned int offset,
  37                           uint64_t *value);
  38
  39    memcached_return_t
  40      memcached_increment_with_initial (memcached_st *ptr,
  41                                        const char *key,
  42                                        size_t key_length,
  43                                        uint64_t offset,
  44                                        uint64_t initial,
  45                                        time_t expiration,
  46                                        uint64_t *value);
  47
  48    memcached_return_t
  49      memcached_decrement_with_initial (memcached_st *ptr,
  50                                        const char *key,
  51                                        size_t key_length,
  52                                        uint64_t offset,
  53                                        uint64_t initial,
  54                                        time_t expiration,
  55                                        uint64_t *value);
  56
  57    memcached_return_t
  58      memcached_increment_by_key (memcached_st *ptr,
  59                                  const char *master_key, size_t master_key_length,
  60                                  const char *key, size_t key_length,
  61                                  unsigned int offset,
  62                                  uint64_t *value);
  63
  64    memcached_return_t
  65      memcached_decrement_by_key (memcached_st *ptr,
  66                                  const char *master_key, size_t master_key_length,
  67                                  const char *key, size_t key_length,
  68                                  unsigned int offset,
  69                                  uint64_t *value);
  70
  71    memcached_return_t
  72      memcached_increment_with_initial_by_key (memcached_st *ptr,
  73                                               const char *master_key,
  74                                               size_t master_key_length,
  75                                               const char *key,
  76                                               size_t key_length,
  77                                               uint64_t offset,
  78                                               uint64_t initial,
  79                                               time_t expiration,
  80                                               uint64_t *value);
  81
  82    memcached_return_t
  83      memcached_decrement_with_initial_by_key (memcached_st *ptr,
  84                                               const char *master_key,
  85                                               size_t master_key_length,
  86                                               const char *key,
  87                                               size_t key_length,
  88                                               uint64_t offset,
  89                                               uint64_t initial,
  90                                               time_t expiration,
  91                                               uint64_t *value);
  92
  93
  94
  95 -----------
  96 DESCRIPTION
  97 -----------
  98
  99
 100 memcached(1) servers have the ability to increment and decrement keys
 101 (overflow and underflow are not detected). This gives you the ability to use
 102 memcached to generate shared sequences of values.
 103
 104 memcached_increment() takes a key and keylength and increments the value by
 105 the offset passed to it. The value is then returned via the unsigned int
 106 value pointer you pass to it.
 107
 108 memcached_decrement() takes a key and keylength and decrements the value by
 109 the offset passed to it. The value is then returned via the unsigned int
 110 value pointer you pass to it.
 111
 112 memcached_increment_with_initial() takes a key and keylength and increments
 113 the value by the offset passed to it. If the object specified by key does
 114 not exist, one of two things may happen: If the expiration value is
 115 MEMCACHED_EXPIRATION_NOT_ADD, the operation will fail. For all other
 116 expiration values, the operation will succeed by seeding the value for that
 117 key with a initial value to expire with the provided expiration time. The
 118 flags will be set to zero.The value is then returned via the unsigned int
 119 value pointer you pass to it.
 120
 121 memcached_decrement_with_initial() takes a key and keylength and decrements
 122 the value by the offset passed to it. If the object specified by key does
 123 not exist, one of two things may happen: If the expiration value is
 124 MEMCACHED_EXPIRATION_NOT_ADD, the operation will fail. For all other
 125 expiration values, the operation will succeed by seeding the value for that
 126 key with a initial value to expire with the provided expiration time. The
 127 flags will be set to zero.The value is then returned via the unsigned int
 128 value pointer you pass to it.
 129
 130 memcached_increment_by_key(), memcached_decrement_by_key(),
 131 memcached_increment_with_initial_by_key(), and
 132 memcached_decrement_with_initial_by_key() are master key equivalents of the
 133 above.
 134
 135
 136 ******
 137 RETURN
 138 ******
 139
 140
 141 A value of type \ ``memcached_return_t``\  is returned.
 142 On success that value will be \ ``MEMCACHED_SUCCESS``\ .
 143 Use memcached_strerror() to translate this value to a printable string.
 144
 145
 146 ****
 147 HOME
 148 ****
 149
 150
 151 To find out more information please check:
 152 `https://launchpad.net/libmemcached <https://launchpad.net/libmemcached>`_
 153
 154
 155 ******
 156 AUTHOR
 157 ******
 158
 159
 160 Brian Aker, <brian@tangent.org>
 161
 162
 163 --------
 164 SEE ALSO
 165 --------
 166
 167
 168 :manpage:`memcached(1)` :manpage:`libmemcached(3)` :manpage:`memcached_strerror(3)`