LIBMEMCACHED(3)libmemcachedLIBMEMCACHED(3)NAMElibmemcached - Introducing the C Client Library for memcached
SYNOPSIS
#include <libmemcached/memcached.h>
Compile and link with -lmemcached
----
libMemcached is an open source C/C++ client library and tools for the
memcached server (http://memcached.org/). It has been designed to be
light on memory usage, thread safe, and provide full access to server
side methods.
libMemcached was designed to provide the greatest number of options to
use Memcached. Some of the features provided:
1. Asynchronous and Synchronous Transport Support.
2. Consistent Hashing and Distribution.
3. Tunable Hashing algorithm to match keys.
4. Access to large object support.
5. Local replication.
6. A complete reference guide and documentation to the API.
7. Tools to Manage your Memcached networks.
DESCRIPTION
"Memcached is a high-performance, distributed memory object caching
system, generic in nature, but intended for use in speeding up dynamic
web applications by alleviating database load." http://memcached.org/
libmemcached is a small, thread-safe client library for the memcached
protocol. The code has all been written to allow for both web and
embedded usage. It handles the work behind routing individual keys to
specific servers specified by the developer (and values are matched
based on server order as supplied by the user). It implements a modular
and consistent method of object distribution.
There are multiple implemented routing and hashing methods. See the
memcached_behavior_set() manpage for more information.
All operations are performed against a memcached_st structure. These
structures can either be dynamically allocated or statically allocated
and then initialized by memcached_create(). Functions have been written
in order to encapsulate the memcached_st. It is not recommended that
you operate directly against the structure.
Nearly all functions return a memcached_return_t value. This value can
be translated to a printable string with memcached_strerror.
Objects are stored on servers by hashing keys. The hash value maps the
key to a particular server. All clients understand how this hashing
works, so it is possibly to reliably both push data to a server and
retrieve data from a server.
Group keys can be optionally used to group sets of objects with
servers.
Namespaces are supported, and can be used to partition caches so that
multiple applications can use the same memcached servers.
memcached_st structures are thread-safe, but each thread must contain
its own structure (that is, if you want to share these among threads
you must provide your own locking). No global variables are used in
this library.
If you are working with GNU autotools you will want to add the follow‐
ing to your COPYING to properly include libmemcached in your applica‐
tion.
PKG_CHECK_MODULES(DEPS, libmemcached >= 0.8.0) AC_SUBST(DEPS_CFLAGS)AC_SUBST(DEPS_LIBS)
Some features of the library must be enabled through memcached_behav‐
ior_set().
Hope you enjoy it!
CONSTANTS
A number of constants have been provided for in the library.
MEMCACHED_DEFAULT_PORT
The default port used by memcached(3).
MEMCACHED_MAX_KEY
Default maximum size of a key (which includes the null pointer).
Master keys have no limit, this only applies to keys used for
storage.
MEMCACHED_MAX_KEY
Default size of key (which includes the null pointer).
MEMCACHED_STRIDE
This is the "stride" used in the consistent hash used between
replicas.
MEMCACHED_MAX_HOST_LENGTH
Maximum allowed size of the hostname.
LIBMEMCACHED_VERSION_STRING
String value of libmemcached version such as "1.23.4"
LIBMEMCACHED_VERSION_HEX
Hex value of the version number. "0x00048000" This can be used
for comparing versions based on number.
MEMCACHED_PREFIX_KEY_MAX_SIZE
Maximum length allowed for namespacing of a key.
THREADS AND PROCESSES
When using threads or forked processes it is important to keep one
instance of memcached_st per process or thread. Without creating your
own locking structures you can not share a single memcached_st. How‐
ever, you can call memcached_quit() on a memcached_st and then use the
resulting cloned structure.
HOME
To find out more information please check: http://libmemcached.org/
SEE ALSOmemcached(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_exam‐
ples(3)memcached_clone(3)memcached_free(3)memcached_server_add(3)memcached_server_push(3)memcached_add(3)memcached_get(3) mem‐
cached_server_count(3)memcached_create(3)memcached_increment(3) mem‐
cached_server_list(3)memcached_set(3)memcached_decrement(3) mem‐
cached_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) mem‐
cached_result_create(3)memcached_result_free(3) mem‐
cached_result_key_value(3)memcached_result_key_length(3) mem‐
cached_result_value(3)memcached_result_length(3) mem‐
cached_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) mem‐
cached_delete_by_key(3)memcached_fetch_execute(3) memcached_call‐
back_get(3)memcached_callback_set(3)memcached_version(3) mem‐
cached_lib_version(3)memcached_result_set_value(3)memcached_dump(3)memdump(1)memcached_set_memory_allocators(3) memcached_get_mem‐
ory_allocators(3)memcached_get_user_data(3)memcached_set_user_data(3)AUTHOR
Brian Aker
COPYRIGHT
2011-2013, Brian Aker DataDifferential, http://datadifferential.com/
1.0.18 February 09, 2014 LIBMEMCACHED(3)
