MEMCACHED_POOL(3)

📦
version 1.1.4 · 13 versions
, in fedora 43

🫶 MEMCACHED_POOL(3) 🫶

okay so bestie, pull up a chair, because this is memcached_pool from the libmemcached-awesome manual, section 3, and it's genuinely so good. it's the connection-pool era of your life. no more cloning memcached_st objects over and over like a peasant. let's get into it 💅

🌸 NAME 🌸

memcached_pool — libmemcached Documentation ✨

✨ SYNOPSIS ✨

#include <libmemcachedutil-1.0/pool.h>

Compile and link with -lmemcachedutil -lmemcached

typedef struct memcached_pool_st memcached_pool_st

🎀 memcached_pool()

memcached_pool_st *memcached_pool(const char *option_string, size_t
option_string_length)

Parameters

  • option_string — the configuration string 🧚
  • option_string_length — length of options_string without any trailing zero byte

Returns

an allocated and initialized memcached_pool_st instance on success, or nullptr on failure 😭

🎀 memcached_pool_destroy()

memcached_st *memcached_pool_destroy(memcached_pool_st *pool)

Parameters

  • pool — initialized memcached_pool_st instance to free

Returns

pointer to the 'master' memcached_st instance, by legacy 👑

🎀 memcached_pool_fetch()

memcached_st *memcached_pool_fetch(memcached_pool_st *pool, struct
timespec *relative_time, memcached_return_t *rc)

Added in version 0.53: Synonym for memcached_pool_pop

Parameters

  • pool — initialized memcached_pool_st instance
  • relative_time — time to block the thread and wait for a connection to become available when the pool size is exceeded, unless nullptr ⏳
  • rc — out pointer to memcached_return_t

Returns

pointer to an available memcached_st instance 🌈

🎀 memcached_pool_release()

memcached_return_t memcached_pool_release(memcached_pool_st *pool,
memcached_st *mmc)

Added in version 0.53: Synonym for memcached_pool_push.

Parameters

  • pool — initialized memcached_pool_st instance
  • mmc — the memcached_st instance to return to the pool 🫶

Returns

memcached_return_t indicating success

🎀 memcached_pool_behavior_set()

memcached_return_t memcached_pool_behavior_set(memcached_pool_st *pool,
memcached_behavior_t flag, uint64_t data)

Parameters

  • pool — initialized memcached_pool_st instance
  • flag — the behavior to change
  • value — the value to set for flag

Returns

memcached_return_t indicating success

🎀 memcached_pool_behavior_get()

memcached_return_t memcached_pool_behavior_get(memcached_pool_st *pool,
memcached_behavior_t flag, uint64_t *value)

Parameters

  • pool — initialized memcached_pool_st instance
  • flag — the behavior to read
  • value — out pointer to receive the set value of flag 🔍

Returns

memcached_return_t indicating success

🎀 memcached_pool_create()

memcached_pool_st *memcached_pool_create(memcached_st *mmc, int initial,
int max)
Deprecated since version 0.46: Use memcached_pool() 💀

🎀 memcached_pool_pop()

memcached_st *memcached_pool_pop(memcached_pool_st *pool, bool block,
memcached_return_t *rc)
Deprecated since version 0.53: Use memcached_pool_fetch() 💀

🎀 memcached_pool_push()

memcached_return_t memcached_pool_push(memcached_pool_st *pool,
memcached_st *mmc)
Deprecated since version 0.53: Use memcached_pool_release() 💀

💖 DESCRIPTION 💖

okay so, the whole point: memcached_pool() is used to create a connection pool of objects that you can use to remove the overhead of calling memcached_clone for short lived memcached_st objects. that's it, that's the glow-up. for the deets on the format of the configuration string, go check out libmemcached Configuration 📚

memcached_pool_destroy() is used to destroy the connection pool created with memcached_pool_create() and release all the allocated resources. it will return the pointer to the memcached_st structure passed as an argument to memcached_pool_create(), and it returns the ownership of the pointer to the caller when it was created with memcached_pool_create(). otherwise NULL is returned. (yes, that's a double period in the source, we're keeping the vibes fr fr)

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 become available if we try to exceed the maximum size. you need to specify time in relative time, not absolute, ok? ⏰

memcached_pool_release() is used to return a connection structure back to the pool. give it back bestie, don't hoard 🫴

memcached_pool_behavior_get() and memcached_pool_behavior_set() are used to get/set behavior flags on all connections in the pool. every single one. the whole squad 🫂

both memcached_pool_release() and memcached_pool_fetch() are thread safe. iconic behavior honestly 🌈

⭐ RETURN VALUE ⭐

memcached_pool_destroy() returns the pointer (and ownership) to the memcached_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 structure from the pool (or NULL if an allocation cannot be satisfied).

memcached_pool_release() returns MEMCACHED_SUCCESS upon success ✨

memcached_pool_behavior_get() and memcached_pool_behavior_get() return MEMCACHED_SUCCESS upon success. (yep, the original says memcached_pool_behavior_get() twice, and we are NOT editing the queen's words 💅)

memcached_pool_fetch() may return MEMCACHED_TIMEOUT if a timeout occurs while waiting for a free memcached_st instance, and MEMCACHED_NOTFOUND if no memcached_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 will be returned. 🚫

🦋 SEE ALSO 🦋

memcached(1) libmemcached(3) libmemcached_configuration(3) ‐ memcached_strerror(3)

and that's the whole page bestie!! 🎀 version 1.1, dated Jul 24, 2025, straight from the libmemcached-awesome girlies. go build a pool, stay thread safe, and remember: fetch it, release it, don't leak it 💖✨🦋

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