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Introducing the C Client Library for memcached¶

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C/C++ Client Library for memcached¶

SYNOPSIS¶

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#include <libmemcached/memcached.h>

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Compile and link with -lmemcached

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#include <libmemcached/memcached.h>
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Compile and link with -lmemcached
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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.

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libMemcached was designed to provide the greatest number of options to use Memcached. Some of the features provided:

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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.

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libmemcached was designed to provide the greatest number of options to use +Memcached. Some of the features provided:

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  1. Asynchronous and Synchronous Transport Support.

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  2. Consistent Hashing and Distribution.

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  3. Tunable Hashing algorithm to match keys.

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  4. Access to large object support.

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  5. Local replication.

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  6. A complete reference guide and documentation to the API.

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  7. Tools to Manage your Memcached networks.

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  8. Asynchronous and Synchronous Transport Support.
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  9. Consistent Hashing and Distribution.
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  10. Tunable Hashing algorithm to match keys.
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  11. Access to large object support.
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  12. Local replication.
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  13. A complete reference guide and documentation to the API.
    14. +
  14. Tools to Manage your Memcached networks.

DESCRIPTION¶

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“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/

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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.

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"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/

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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.

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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.

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Nearly all functions return a memcached_return_t value. -This value can be translated to a printable string with -memcached_strerror.

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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.

+memcached_behavior_set() manpage for more information.

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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.

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Nearly all functions return a memcached_return_t value. This value can be +translated to a printable string with memcached_strerror().

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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.

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Namespaces are supported, and can be used to partition caches so that multiple applications can use the same memcached servers.

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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.

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If you are working with GNU autotools you will want to add the following to -your COPYING to properly include libmemcached in your application.

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PKG_CHECK_MODULES(DEPS, libmemcached >= 0.8.0) -AC_SUBST(DEPS_CFLAGS) -AC_SUBST(DEPS_LIBS)

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Some features of the library must be enabled through memcached_behavior_set().

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Hope you enjoy it!

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CONSTANTS¶

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A number of constants have been provided for in the library.

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-MEMCACHED_DEFAULT_PORT¶
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The default port used by memcached(3).

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-MEMCACHED_MAX_KEY¶
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Default maximum size of a key (which includes the null pointer). Master keys -have no limit, this only applies to keys used for storage.

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-MEMCACHED_MAX_BUFFER¶
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Default size of read/write buffers (which includes the null pointer).

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-MEMCACHED_STRIDE¶
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This is the “stride” used in the consistent hash used between replicas.

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-MEMCACHED_MAX_HOST_LENGTH¶
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Maximum allowed size of the hostname.

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-LIBMEMCACHED_VERSION_STRING¶
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String value of libmemcached version such as “1.23.4”

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-LIBMEMCACHED_VERSION_HEX¶
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Hex value of the version number. “0x00048000” This can be used for comparing versions based on number.

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-MEMCACHED_PREFIX_KEY_MAX_SIZE¶
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Maximum length allowed for namespacing of a key.

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Namespaces are supported, and can be used to partition caches so that multiple +applications can use the same memcached servers.

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Some features of the library must be enabled through memcached_behavior_set().

THREADS AND PROCESSES¶

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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. However, -you can call memcached_quit() on a memcached_st and then use the resulting cloned structure.

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No global variables are used in this library.

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memcached_st structures are thread-safe, but 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. However, you can call memcached_quit() on a memcached_st and +then use the resulting cloned structure.

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HOME¶

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To find out more information please check: -http://libmemcached.org/

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SYSTEMTAP¶

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libmemcached can be built to support Systemtap on Linux when enabled at +compile time.

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Please see stap(1) and dtrace(1) for more information +about Systemtap.

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CLIENT PROGRAMS¶

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libmemcached comes with a few useful client programs:

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SEE ALSO¶

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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_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) -memcached_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) memcached_result_set_value(3) -memcached_dump(3) memdump(1) -memcached_set_memory_allocators(3) -memcached_get_memory_allocators(3) -memcached_get_user_data(3) memcached_set_user_data(3)

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@@ -850,10 +275,10 @@ you can call - + - +
@@ -862,7 +287,7 @@ you can call

- © Copyright 2011-2020 Brian Aker, Michael Wallner + © Copyright