MEMCACHED_PREPEND_BY_KEY(3)					   libmemcached 				       MEMCACHED_PREPEND_BY_KEY(3)

NAME

       memcached_prepend_by_key - Appending to or Prepending to data on the server

       Appending or Prepending to data on the server

SYNOPSIS

       #include <libmemcached/memcached.h>

       memcached_return_t   memcached_prepend(memcached_st *ptr,  const  char *key,  size_t key_length,  const	char *value,  size_t value_length,
       time_t expiration, uint32_t flags)

       memcached_return_t  memcached_append(memcached_st *ptr,	const  char *key,  size_t key_length,  const   char *value,   size_t value_length,
       time_t expiration, uint32_t flags)

       memcached_return_t   memcached_prepend_by_key(memcached_st *ptr,   const   char *group_key,   size_t group_key_length,	const	char *key,
       size_t key_length, const char *value, size_t value_length, time_t expiration, uint32_t flags)

       memcached_return_t   memcached_append_by_key(memcached_st *ptr,	 const	 char *group_key,   size_t group_key_length,   const	char *key,
       size_t key_length, const char *value, size_t value_length, time_t expiration, uint32_t flags)

       Compile and link with -lmemcached

DESCRIPTION

       memcached_prepend()  and  memcached_append  are used to modify information on a server. All methods take a key, and its length to store the
       object. Keys are currently limited to 250 characters when using either a version of memcached which is 1.4 or below, or when using the text
       protocol.  You  must supply both a value and a length. Optionally you may test an expiration time for the object and a 16 byte value (it is
       meant to be used as a bitmap). "flags" is a 4byte space that is stored alongside of the main value. Many sub libraries  make  use  of  this
       field, so in most cases users should avoid making use of it.

       memcached_prepend() places a segment of data before the last piece of data stored. Currently expiration and key are not used in the server.

       memcached_append()  places  a segment of data at the end of the last piece of data stored. Currently expiration and key are not used in the
       server.

       memcached_prepend_by_key() and memcached_append_by_key() methods both behave in a similar method as the non key methods. The difference	is
       that they use their group_key parameter to map objects to particular servers.

       If you are looking for performance, memcached_set() with non-blocking IO is the fastest way to store data on the server.

       All of the above functions are testsed with the MEMCACHED_BEHAVIOR_USE_UDP behavior enabled. However, when using these operations with this
       behavior on, there are limits to the size of the payload being sent to the server.  The reason for  these  limits  is  that  the  Memcached
       Server  does  not  allow  multi-datagram requests and the current server implementation sets a datagram size to 1400 bytes. Due to protocol
       overhead, the actual limit of the user supplied data is less than 1400 bytes and depends on the protocol in use as, well as  the  operation
       being executed. When running with the binary protocol, MEMCACHED_BEHAVIOR_BINARY_PROTOCOL, the size of the key,value, flags and expiry com-
       bined may not exceed 1368 bytes. When running with the ASCII protocol, the exact limit fluctuates depending on which function is being exe-
       cuted  and  whether  the  function  is a cas operation or not. For non-cas ASCII set operations, there are at least 1335 bytes available to
       split among the key, key_prefix, and value; for cas ASCII operations there are at least 1318  bytes  available  to  split  among  the  key,
       key_prefix and value. If the total size of the command, including overhead, exceeds 1400 bytes, a MEMCACHED_WRITE_FAILURE will be returned.

RETURN

       All methods return a value of type memcached_return_t.  On success the value will be MEMCACHED_SUCCESS.	Use memcached_strerror() to trans-
       late this value to a printable string.

HOME

       To find out more information please check: http://libmemcached.org/

SEE ALSO

       memcached(1) libmemached(3) memcached_strerror(3) memcached_set(3) memcached_add(3) memcached_cas(3) memcached_replace(3)

AUTHOR

       Brian Aker

COPYRIGHT

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

1.0.16								 January 31, 2013				       MEMCACHED_PREPEND_BY_KEY(3)