3 libmemcached - Client library for memcached
7 C Client Library for memcached (libmemcached, -lmemcached)
11 #include <memcached.h>
15 "Memcached is a high-performance, distributed memory object caching
16 system, generic in nature, but intended for use in speeding up dynamic web
17 applications by alleviating database load." L<http://danga.com/memcached/>
19 B<libmemcached> is a small, thread-safe client library for the
20 memcached protocol. The code has all been written with an eye to allow
21 for both web and embedded usage. It handles the work behind routing
22 particular keys to specific servers that you specify (and values are
23 matched based on server order as supplied by you). It implements both
24 a modula and consistent method of object distribution.
26 There are multiple implemented routing and hashing methods. See the
27 memcached_behavior_set() manpage.
29 All operations are performed against a C<memcached_st> structure.
30 These structures can either be dynamically allocated or statically
31 allocated and then initialized by memcached_create(). Functions have been
32 written in order to encapsulate the C<memcached_st>. It is not
33 recommended that you operate directly against the structure.
35 Nearly all functions return a C<memcached_return> value.
36 This value can be translated to a printable string with memcached_strerr(3).
38 Partitioning based on keys is supported in the library. Using the key partioning
39 functions it is possible to group sets of object onto servers.
41 Replication can be done across multiple nodes. libmemcached(3) will spread
42 data out when consistent hashing has been enabled and replication has been
43 specified to send data to more then one node. This feature is considered
44 very experimental at this stage.
46 C<memcached_st> structures are thread-safe, but each thread must
47 contain its own structure (that is, if you want to share these among
48 threads you must provide your own locking). No global variables are
51 If you are working with GNU autotools you will want to add the following to
52 your configure.ac to properly include libmemcached in your application.
54 PKG_CHECK_MODULES(DEPS, libmemcached >= 0.8.0)
58 Some features of the library must be enabled through memcached_behavior_set().
64 A number of constants have been provided for in the library.
68 =item MEMCACHED_DEFAULT_PORT
70 The default port used by memcached(3).
72 =item MEMCACHED_MAX_KEY
74 Default maximum size of a key (which includes the null pointer). Master keys
75 have no limit, this only applies to keys used for storage.
77 =item MEMCACHED_MAX_KEY
79 Default size of key (which includes the null pointer).
81 =item MEMCACHED_STRIDE
83 This is the "stride" used in the consistent hash used between replicas.
85 =item MEMCACHED_MAX_HOST_LENGTH
87 Maximum allowed size of the hostname.
89 =item MEMCACHED_VERSION_STRING
91 String value of libmemcached version such as "1.23.4"
93 =item MEMCACHED_MAJOR_VERSION
95 Major version value. Such as 1.23.4, would be 1
97 =item MEMCACHED_MINOR_VERSION
99 Major version value. Such as 1.23.4, would be 23
101 =item MEMCACHED_MICRO_VERSION
103 Major version value. Such as 1.23.4, would be 4
110 =head1 THREADS AND PROCESSES
112 When using threads or forked processes it is important to keep an instance
113 of C<memcached_st> per process or thread. Without creating your own locking
114 structures you can no share a single C<memcached_st>. You can though call
115 memcached_close(3) on a C<memcached_st> and then use the resulting cloned
120 To find out more information please check:
121 L<http://tangent.org/552/libmemcached.html>
125 Brian Aker, E<lt>brian@tangent.orgE<gt>
129 memcached(1) libmemcached_examples(3) libmemcached(1) memcat(1) memcp(1) memflush(1) memrm(1) memslap(1) memstat(1) memcached_fetch(3) memcached_replace(3) memcached_server_list_free(3) libmemcached_examples(3) memcached_clone(3) memcached_free(3) memcached_server_add(3) memcached_server_push(3) memcached_add(3) memcached_get(3) memcached_server_count(3) memcached_servers_parse(3) memcached_create(3) memcached_increment(3) memcached_server_list(3) memcached_set(3) memcached_decrement(3) memcached_mget(3) memcached_server_list_append(3) memcached_strerror(3) memcached_delete(3) memcached_quit(3) memcached_server_list_count(3) memcached_verbosity(3) memcached_server_add_unix_socket(3) memcahed_result_create(3) memcached_result_free(3) memcached_result_key_value(3) memcached_result_key_length(3) memcached_result_value(3) memcached_result_length(3) memcached_result_flags(3) memcached_result_cas(3) memcached_result_st(3) memcached_append(3) memcached_prepend(3) memcached_fetch_result(3) memerror(1) memcached_get_by_key(3) memcached_mget_by_key(3) memcached_delete_by_key(3) memcached_fetch_execute(3) memcached_callback_get(3) memcached_callback_set(3) memcached_version(3) memcached_lib_version(3)