-==========================
-Storing and Replacing Data
-==========================
+=========================================================
+Store, replace, add, or atomically add data to the server
+=========================================================
-
-Store value on server
+.. index:: object: memcached_st
--------
--------
-
#include <libmemcached/memcached.h>
.. c:function:: memcached_return_t memcached_set (memcached_st *ptr, const char *key, size_t key_length, const char *value, size_t value_length, time_t expiration, uint32_t flags);
.. c:function:: memcached_return_t memcached_replace (memcached_st *ptr, const char *key, size_t key_length, const char *value, size_t value_length, time_t expiration, uint32_t flags);
-.. c:function:: 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)
-
-.. c:function:: 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)
-
-.. c:function:: memcached_return_t memcached_cas(memcached_st *ptr, const char *key, size_t key_length, const char *value, size_t value_length, time_t expiration, uint32_t flags, uint64_t cas);
-
-.. c:function:: memcached_return_t memcached_set_by_key(memcached_st *ptr, const char *master_key, size_t master_key_length, const char *key, size_t key_length, const char *value, size_t value_length, time_t expiration, uint32_t flags);
+.. c:function:: memcached_return_t memcached_set_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);
-.. c:function:: memcached_return_t memcached_add_by_key(memcached_st *ptr, const char *master_key, size_t master_key_length, const char *key, size_t key_length, const char *value, size_t value_length, time_t expiration, uint32_t flags);
+.. c:function:: memcached_return_t memcached_add_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);
-.. c:function:: memcached_return_t memcached_replace_by_key(memcached_st *ptr, const char *master_key, size_t master_key_length, const char *key, size_t key_length, const char *value, size_t value_length, time_t expiration, uint32_t flags);
-
-.. c:function:: memcached_return_t memcached_prepend_by_key(memcached_st *ptr, const char *master_key, size_t master_key_length, const char *key, size_t key_length, const char *value, size_t value_length, time_t expiration, uint32_t flags);
-
-.. c:function:: memcached_return_t memcached_append_by_key(memcached_st *ptr, const char *master_key, size_t master_key_length, const char *key, size_t key_length, const char *value, size_t value_length, time_t expiration, uint32_t flags);
-
-.. c:function:: memcached_return_t memcached_cas_by_key(memcached_st *ptr, const char *master_key, size_t master_key_length, const char *key, size_t key_length, const char *value, size_t value_length, time_t expiration, uint32_t flags, uint64_t cas);
+.. c:function:: memcached_return_t memcached_replace_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
memcached_set(), memcached_add(), and memcached_replace() are all used to
store information on the server. All methods take a key, and its length to
-store the object. Keys are currently limited to 250 characters by the
-memcached(1) server. You must also supply a value and a length. Optionally you
-may tests an expiration time for the object and a 16 byte value (it is
-meant to be used as a bitmap).
+store the object. Keys are currently limited to 250 characters when using either a version of memcached(1) 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_set() will write an object to the server. If an object already
exists it will overwrite what is in the server. If the object does not exist
memcached_add() adds an object to the server. If the object is found on the
server an error occurs, otherwise the value is stored.
-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_cas() overwrites data in the server as long as the "cas" value is
still the same in the server. You can get the cas value of a result by
calling memcached_result_cas() on a memcached_result_st(3) structure. At the point
for it in libmemcached(3) is optional. Please see memcached_set() for
information on how to do this.
-memcached_set_by_key(), memcached_add_by_key(), memcached_replace_by_key(),
-memcached_prepend_by_key(), memcached_append_by_key_by_key(),
-memcached_cas_by_key() methods all behave in a similar method as the non key
-methods. The difference is that they use their master_key parameter to map
+memcached_set_by_key(), memcached_add_by_key(), and memcached_replace_by_key()
+methods all 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. But when using these operations with this behavior on, there
+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 Memcahed Server does not allow multi-datagram requests
+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
+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
To find out more information please check:
-`https://launchpad.net/libmemcached <https://launchpad.net/libmemcached>`_
+`http://libmemcached.org/ <http://libmemcached.org/>`_
--------
--------
-memcached(1) libmemached(3) memcached_strerror(3)
+memcached(1) libmemached(3) memcached_strerror(3) memcached_prepend(3) memcached_cas(3) memcached_append(3)
projects / m6w6 / libmemcached / blobdiff