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MEMCACHED_APPEND(3)              libmemcached              MEMCACHED_APPEND(3)


NAME

       memcached_append - 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/

1.0.18                         February 9, 2014            MEMCACHED_APPEND(3)

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