memcached_callback_set - libmemcached Documentation Get and set a callback
#include <libmemcached/memcached.h> memcached_callback_t memcached_return_t memcached_callback_set(memcached_st *ptr, memcached_callback_t flag, const void *data) void * memcached_callback_get(memcached_st *ptr, memcached_callback_t flag, memcached_return_t *error) Compile and link with -lmemcached
libmemcached MEMCACHED_CALLBACK_SET(3libmemcached)
NAME
memcached_callback_set - libmemcached Documentation
Get and set a callback
SYNOPSIS
#include <libmemcached/memcached.h>
memcached_callback_t
memcached_return_t memcached_callback_set(memcached_st *ptr,
memcached_callback_t flag, const void *data)
void * memcached_callback_get(memcached_st *ptr,
memcached_callback_t flag, memcached_return_t *error)
Compile and link with -lmemcached
DESCRIPTION
libmemcached(3) can have callbacks set key execution points. These
either provide function calls at points in the code, or return pointers
to structures for particular usages.
memcached_callback_get() takes a callback flag and returns the struc-
ture or function set by memcached_callback_set().
memcached_callback_set() changes the function/structure assigned by a
callback flag. No connections are reset.
You can use MEMCACHED_CALLBACK_USER_DATA to provide custom context if
required for any of the callbacks.
MEMCACHED_CALLBACK_CLEANUP_FUNCTION
When memcached_delete() is called this function will be excuted. At the
point of its execution all connections are closed.
MEMCACHED_CALLBACK_CLONE_FUNCTION
When memcached_delete() is called this function will be excuted. At
the point of its execution all connections are closed.
MEMCACHED_CALLBACK_PREFIX_KEY
See MEMCACHED_CALLBACK_NAMESPACE
MEMCACHED_CALLBACK_NAMESPACE
You can set a value which will be used to create a domain for your
keys. The value specified here will be prefixed to each of your keys.
The value can not be greater then MEMCACHED_PREFIX_KEY_MAX_SIZE - 1 and
will reduce MEMCACHED_MAX_KEY by the value of your key.
The prefix key is only applied to the primary key, not the master key.
MEMCACHED_FAILURE will be returned if no key is set. In the case of a
key which is too long, MEMCACHED_BAD_KEY_PROVIDED will be returned.
If you set a value with the value being NULL then the prefix key is
disabled.
MEMCACHED_CALLBACK_USER_DATA
This allows you to store a pointer to a specifc piece of data. This can
be retrieved from inside of memcached_fetch_execute(). Cloning a mem-
cached_st will copy the pointer to the clone.
MEMCACHED_CALLBACK_MALLOC_FUNCTION
Deprecated since version <0.32: Use memcached_set_memory_allocators
instead.
MEMCACHED_CALLBACK_REALLOC_FUNCTION
Deprecated since version <0.32: Use memcached_set_memory_allocators
instead.
MEMCACHED_CALLBACK_FREE_FUNCTION
Deprecated since version <0.32: Use memcached_set_memory_allocators
instead.
MEMCACHED_CALLBACK_GET_FAILURE
This function implements the read through cache behavior. On failure of
retrieval this callback will be called.
You are responsible for populating the result object provided. This
result object will then be stored in the server and returned to the
calling process.
You must clone the memcached_st in order to make use of it. The value
will be stored only if you return MEMCACHED_SUCCESS or MEM-
CACHED_BUFFERED. Returning MEMCACHED_BUFFERED will cause the object to
be buffered and not sent immediatly (if this is the default behavior
based on your connection setup this will happen automatically).
The prototype for this is:
memcached_return_t (*memcached_trigger_key)(memcached_st *ptr, char
*key, size_t key_length, memcached_result_st *result);
MEMCACHED_CALLBACK_DELETE_TRIGGER
This function implements a trigger upon successful deletion of a key.
The memcached_st structure will need to be cloned in order to make use
of it.
The prototype for this is:
typedef memcached_return_t (*memcached_trigger_delete_key)(memcached_st
*ptr, char *key, size_t key_length);
RETURN
memcached_callback_get() return the function or structure that was pro-
vided. Upon error, nothing is set, null is returned, and the mem-
cached_return_t argument is set to MEMCACHED_FAILURE.
memcached_callback_set() returns MEMCACHED_SUCCESS upon successful set-
ting, otherwise MEMCACHED_FAILURE on error.
HOME
To find out more information please check: http://libmemcached.org/
AUTHOR
Brian Aker, <brian@tangent.org>
ATTRIBUTES
See attributes(7) for descriptions of the following attributes:
+---------------+----------------------+
|ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+---------------+----------------------+
|Availability | library/libmemcached |
+---------------+----------------------+
|Stability | Uncommitted |
+---------------+----------------------+
SEE ALSO
memcached(1) libmemcached(3) memcached_strerror(3)
AUTHOR
Brian Aker
COPYRIGHT
2011-2013, Brian Aker DataDifferential, http://datadifferential.com/
NOTES
Source code for open source software components in Oracle Solaris can
be found at https://www.oracle.com/downloads/opensource/solaris-source-
code-downloads.html.
This software was built from source available at
https://github.com/oracle/solaris-userland. The original community
source was downloaded from https://launchpad.net/libmem-
cached/1.0/1.0.18/+download/libmemcached-1.0.18.tar.gz.
Further information about this software can be found on the open source
community website at http://libmemcached.org/libMemcached.html.
1.0.18 February 09, 2014
MEMCACHED_CALLBACK_SET(3libmemcached)