MEMCACHED_AUTO(3)

💖 memcached_auto — incrementing and decrementing values 💖

okay bestie, welcome to memcached_auto(3) from libmemcached-awesome ✨ this is the page that teaches you how to make counters go up and down in memcached, and honestly? it's giving main character energy.

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🎀 NAME 🎀

memcached_auto — incrementing and decrementing values 🦋

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✨ SYNOPSIS ✨

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

memcached_return_t memcached_increment(memcached_st *ptr, const char
*key, size_t key_length, uint32_t offset, uint64_t *value)

memcached_return_t memcached_decrement(memcached_st *ptr, const char
*key, size_t key_length, uint32_t offset, uint64_t *value)

memcached_return_t memcached_increment_with_initial(memcached_st *ptr,
const char *key, size_t key_length, uint64_t offset, uint64_t initial,
time_t expiration, uint64_t *value)

memcached_return_t memcached_decrement_with_initial(memcached_st *ptr,
const char *key, size_t key_length, uint64_t offset, uint64_t initial,
time_t expiration, uint64_t *value)

memcached_return_t memcached_increment_by_key(memcached_st *ptr, const
char *group_key, size_t group_key_length, const char *key, size_t
key_length, uint32_t offset, uint64_t *value)

memcached_return_t memcached_decrement_by_key(memcached_st *ptr, const
char *group_key, size_t group_key_length, const char *key, size_t
key_length, uint32_t offset, uint64_t *value)

memcached_return_t memcached_increment_with_initial_by_key(memcached_st
*ptr, const char *group_key, size_t group_key_length, const char *key,
size_t key_length, uint64_t offset, uint64_t initial, time_t expiration,
uint64_t *value)

memcached_return_t memcached_decrement_with_initial_by_key(memcached_st
*ptr, const char *group_key, size_t group_key_length, const char *key,
size_t key_length, uint64_t offset, uint64_t initial, time_t expiration,
uint64_t *value)

🌸 Parameters 🌸

• ptr — pointer to an initialized memcached_st struct 💅
• group_key — key namespace 🗂️
• group_key_length — length of the key namespace without any terminating zero 🧮
• key — the key 🔑
• key_length — length of the key without any terminating zero 🧮
• offset — offset to increment/decrement ➕➖
• initial — initial value if key does not exist and expiration is not MEMCACHED_EXPIRATION_NOT_ADD 🌱
• expiration — expiration as a unix timestamp or as relative expiration time in seconds ⏳
• value — the resulting value after initialization/increment/decrement 🏆

💫 Returns 💫

memcached_return_t indicating success ✅

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🔥 DESCRIPTION 🔥

memcached(1) servers have the ability to increment and decrement keys (overflow and underflow are not detected). 😳 this gives you the ability to use memcached to generate shared sequences of values. no cap, that's the whole point.

⚠️ overflow and underflow are not detected — the manpage says it, so i'm saying it, don't come for me 💀

memcached_increment() takes a key and key_length and increments the value by the offset passed to it. the value is then returned via the uint32_t value pointer you pass to it. 🎀

memcached_decrement() takes a key and key_length and decrements the value by the offset passed to it. the value is then returned via the uint32_t value pointer you pass to it. 🎀

memcached_increment_with_initial() takes a key and key_length and increments the value by the offset passed to it. but here's the tea 🍵 — if the object specified by key does not exist, one of two things may happen:

• if the expiration value is MEMCACHED_EXPIRATION_NOT_ADD, the operation will fail 💀
• for all other expiration values, the operation will succeed by seeding the value for that key with a initial value to expire with the provided expiration time. the flags will be set to zero. 🌱

the value is then returned via the uint32_t value pointer you pass to it. and psst — memcached_increment_with_initial is only available when using the binary protocol. 🧚

memcached_decrement_with_initial() takes a key and key_length and decrements the value by the offset passed to it. if the object specified by key does not exist, one of two things may happen:

• if the expiration value is MEMCACHED_EXPIRATION_NOT_ADD, the operation will fail 💀
• for all other expiration values, the operation will succeed by seeding the value for that key with a initial value to expire with the provided expiration time. the flags will be set to zero. 🌱

the value is then returned via the uint32_t value pointer you pass to it. also memcached_decrement_with_initial() is only available when using the binary protocol. 🧚

memcached_increment_by_key(), memcached_decrement_by_key(), memcached_increment_with_initial_by_key(), and memcached_decrement_with_initial_by_key() are master key equivalents of the above. 👑

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👑 RETURN VALUE 👑

a value of type memcached_return_t is returned. on success that value will be MEMCACHED_SUCCESS. use memcached_strerror() to translate this value to a printable string. 🫶

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🌈 SEE ALSO 🌈

memcached(1) libmemcached(3) memcached_strerror(3)

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and that's the whole page bestie, you ate 💅 this was libmemcached-awesome version 1.1, dated Jul 24, 2025 — iconic, no notes, periodt. 🎀✨💖