NAME

       memcached_append_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 combined may not exceed
       1368 bytes. When running with the ASCII protocol, the exact limit fluctuates depending on which  function
       is  being  executed 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 translate 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/