3 memcached_set, memcached_add, memcached_replace
7 C Client Library for memcached (libmemcached, -lmemcached)
11 #include <memcached.h>
14 memcached_set (memcached_st *ptr,
15 char *key, size_t key_length,
16 char *value, size_t value_length,
21 memcached_add (memcached_st *ptr,
22 char *key, size_t key_length,
23 char *value, size_t value_length,
28 memcached_replace (memcached_st *ptr,
29 char *key, size_t key_length,
30 char *value, size_t value_length,
35 memcached_prepend(memcached_st *ptr,
36 char *key, size_t key_length,
37 char *value, size_t value_length,
42 memcached_append(memcached_st *ptr,
43 char *key, size_t key_length,
44 char *value, size_t value_length,
48 memcached_cas(memcached_st *ptr,
49 char *key, size_t key_length,
50 char *value, size_t value_length,
57 memcached_set(), memcached_add(), and memcached_replace() are all used to
58 store information on the server. All methods take a key, and its length to
59 store the object. Keys are currently limited to 250 characters by the
60 memcached(1) server. You must also supply a value and a length. Optionally you
61 may support an expiration time for the object and a 16 byte value (it is
62 meant to be used as a bitmap).
64 memcached_set() will write an object to the server. If an object already
65 exists it will overwrite what is in the server. If the object does not exist
66 it will be written. If you are using the non-blocking mode this function
67 will always return true unless a network error occurs.
69 memcached_replace() replaces an object on the server. If the object is not
70 found on the server an error occurs.
72 memcached_add() adds an object to the server. If the object is found on the
73 server an error occurs, otherwise the value is stored.
75 memcached_prepend() places a segment of data before the last piece of data
76 stored. Currently expiration and key are not used in the server.
78 memcached_append() places a segment of data at the end of the last piece of
79 data stored. Currently expiration and key are not used in the server.
81 memcached_cas() overwrites data in the server as long as the "cas" value is
82 still the same in the server. You can get the cas value of a result by
83 calling memcached_result_cas() on a memcached_result_st(3) structure. At the point
84 that this note was written cas is still buggy in memached. Turning on support
85 for it in libmemcached(3) is optional. Please see memcached_set() for
86 information on how to do this.
88 If you are looking for performance, memcached_set() with non-blocking IO is
89 the fastest way to store data on the server.
93 All methods return a value of type C<memcached_return>.
94 On success the value will be C<MEMCACHED_SUCCESS>.
95 Use memcached_strerror() to translate this value to a printable string.
97 For memcached_replace() and memcached_add(), C<MEMCACHED_NOTSTORED> is a
98 legitmate error in the case of a collision.
102 To find out more information please check:
103 L<http://tangent.org/552/libmemcached.html>
107 Brian Aker, E<lt>brian@tangent.orgE<gt>
111 memcached(1) libmemached(3) memcached_strerror(3)