Scroll to navigation

LIBMEMCACHEDUTIL(3) libmemcached-awesome LIBMEMCACHEDUTIL(3)

NAME

libmemcachedutil - libmemcached Documentation

Utility library for libmemcached

SYNOPSIS

#include <libmemcachedutil-1.0/util.h>
Compile and link with -lmemcachedutil -lmemcached

DESCRIPTION

libmemcachedutil is a small and thread-safe client library that provides extra functionality built on top of libmemcached.

THREADS AND PROCESSES

Do not try to access an instance of memcached_st <#_CPPv412memcached_st> from multiple threads at the same time. If you want to access memcached from multiple threads you should either clone the memcached_st <#_CPPv412memcached_st>, or use the memcached pool implementation. See memcached_pool() <#_CPPv414memcached_poolPKc6size_t>.

Working with memcached pools

SYNOPSIS

#include <libmemcachedutil-1.0/pool.h>
Compile and link with -lmemcachedutil -lmemcached


  • option_string -- configuration <> string
  • option_string_length -- length of options_string without any trailing zero byte

allocated and initialized memcached_pool_st instance on success or nullptr on failure


pool -- initialized memcached_pool_st instance to free
pointer to the 'master' memcached_st <#_CPPv412memcached_st> instance by legacy


Added in version 0.53: Synonym for memcached_pool_pop

  • pool -- initialized memcached_pool_st instance
  • relative_time -- time to block thread and wait for a connection to become available when pool size is exceeded, unless nullptr
  • rc -- out pointer to memcached_return_t <#_CPPv418memcached_return_t>

pointer to an available memcached_st <#_CPPv412memcached_st> instance


Added in version 0.53: Synonym for memcached_pool_push.

  • pool -- initialized memcached_pool_st instance
  • mmc -- the memcached_st <#_CPPv412memcached_st> instance to return to the pool

memcached_return_t <#_CPPv418memcached_return_t> indicating success


  • pool -- initialized memcached_pool_st instance
  • flag -- the behavior <> to change
  • value -- the value to set for flag

memcached_return_t <#_CPPv418memcached_return_t> indicating success


  • pool -- initialized memcached_pool_st instance
  • flag -- the behavior <> to read
  • value -- out pointer to receive the set value of flag

memcached_return_t <#_CPPv418memcached_return_t> indicating success


Deprecated since version 0.46: Use memcached_pool()


Deprecated since version 0.53: Use memcached_pool_fetch()


Deprecated since version 0.53: Use memcached_pool_release()


DESCRIPTION

memcached_pool() is used to create a connection pool of objects you may use to remove the overhead of using memcached_clone for short lived memcached_st <#_CPPv412memcached_st> objects. Please see libmemcached Configuration <> for details on the format of the configuration string.

memcached_pool_destroy() is used to destroy the connection pool created with memcached_pool_create() and release all allocated resources. It will return the pointer to the memcached_st <#_CPPv412memcached_st> structure passed as an argument to memcached_pool_create(), and returns the ownership of the pointer to the caller when created with memcached_pool_create(), otherwise NULL is returned..

memcached_pool_fetch() is used to fetch a connection structure from the connection pool. The relative_time argument specifies if the function should block and wait for a connection structure to be available if we try to exceed the maximum size. You need to specify time in relative time.

memcached_pool_release() is used to return a connection structure back to the pool.

memcached_pool_behavior_get() and memcached_pool_behavior_set() is used to get/set behavior flags on all connections in the pool.

Both memcached_pool_release() and memcached_pool_fetch() are thread safe.

RETURN VALUE

memcached_pool_destroy() returns the pointer (and ownership) to the memcached_st <#_CPPv412memcached_st> structure used to create the pool. If connections are in use it returns NULL.

memcached_pool_pop() returns a pointer to a memcached_st <#_CPPv412memcached_st> structure from the pool (or NULL if an allocation cannot be satisfied).

memcached_pool_release() returns MEMCACHED_SUCCESS <#_CPPv4N18memcached_return_t17MEMCACHED_SUCCESSE> upon success.

memcached_pool_behavior_get() and memcached_pool_behavior_get() return MEMCACHED_SUCCESS <#_CPPv4N18memcached_return_t17MEMCACHED_SUCCESSE> upon success.

memcached_pool_fetch() may return MEMCACHED_TIMEOUT <#_CPPv4N18memcached_return_t17MEMCACHED_TIMEOUTE> if a timeout occurs while waiting for a free memcached_st <#_CPPv412memcached_st> instance, MEMCACHED_NOTFOUND <#_CPPv4N18memcached_return_t18MEMCACHED_NOTFOUNDE> if no memcached_st <#_CPPv412memcached_st> instance was available, respectively.

Note:

If any method returns MEMCACHED_IN_PROGRESS then a lock on the pool could not be obtained.

If any of the parameters passed to any of these functions is invalid, MEMCACHED_INVALID_ARGUMENTS <#_CPPv4N18memcached_return_t27MEMCACHED_INVALID_ARGUMENTSE> will be returned.



SEE ALSO

memcached(1) <https://linux.die.net/man/1/memcached> libmemcached(3) <https://linux.die.net/man/3/libmemcached> libmemcached_configuration(3) <https://linux.die.net/man/3/libmemcached_configuration> memcached_strerror(3) <https://linux.die.net/man/3/memcached_strerror>

SEE ALSO

libmemcached(3) <https://linux.die.net/man/3/libmemcached> memcached_pool(3) <https://linux.die.net/man/3/memcached_pool> memcached_pool_destroy(3) <https://linux.die.net/man/3/memcached_pool_destroy> memcached_pool_pop(3) <https://linux.die.net/man/3/memcached_pool_pop> memcached_pool_push(3) <https://linux.die.net/man/3/memcached_pool_push>

January 17, 2026 1.1