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MEMCACHED_CALLBACK_SET(3)	 libmemcached	     MEMCACHED_CALLBACK_SET(3)

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 ei-
       ther 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 in-
       stead.

       MEMCACHED_CALLBACK_REALLOC_FUNCTION

       Deprecated since	version	<0.32: Use memcached_set_memory_allocators in-
       stead.

       MEMCACHED_CALLBACK_FREE_FUNCTION

       Deprecated since	version	<0.32: Use memcached_set_memory_allocators in-
       stead.

       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 re-
       sult object will	then be	stored in the server and returned to the call-
       ing 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>

SEE ALSO
       memcached(1) libmemcached(3) memcached_strerror(3)

AUTHOR
       Brian Aker

COPYRIGHT
       2011-2013, Brian	Aker DataDifferential, http://datadifferential.com/

1.0.18			       February	09, 2014     MEMCACHED_CALLBACK_SET(3)

NAME | SYNOPSIS | DESCRIPTION | RETURN | HOME | AUTHOR | SEE ALSO | AUTHOR | COPYRIGHT

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