-.TH "MEMCACHED_CAS" "3" "April 07, 2011" "0.47" "libmemcached"
+.TH "MEMCACHED_CAS" "3" "June 10, 2011" "0.47" "libmemcached"
.SH NAME
-memcached_cas \- libmemcached Documentation
+memcached_cas \- Working with data on the server in an atomic fashion
.
.nr rst2man-indent-level 0
.
..
.\" Man page generated from reStructeredText.
.
-.sp
-Store value on server
-.SH LIBRARY
-.sp
-C Client Library for memcached (libmemcached, \-lmemcached)
.SH SYNOPSIS
.sp
-.nf
-.ft C
#include <libmemcached/memcached.h>
-
-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);
-
-memcached_return_t
- memcached_add (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_replace (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(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_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);
-
-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);
-
-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);
-
-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);
-
-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);
-
-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);
-
-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);
-.ft P
-.fi
+.INDENT 0.0
+.TP
+.B 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);
+.UNINDENT
+.INDENT 0.0
+.TP
+.B memcached_return_t memcached_cas_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, uint64_t cas);
+.UNINDENT
+.sp
+Compile and link with \-lmemcached
.SH DESCRIPTION
.sp
-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 support an expiration time for the object and a 16 byte value (it is
-meant to be used as a bitmap).
-.sp
-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
-it will be written. If you are using the non\-blocking mode this function
-will always return true unless a network error occurs.
-.sp
-memcached_replace() replaces an object on the server. If the object is not
-found on the server an error occurs.
-.sp
-memcached_add() adds an object to the server. If the object is found on the
-server an error occurs, otherwise the value is stored.
-.sp
-memcached_prepend() places a segment of data before the last piece of data
-stored. Currently expiration and key are not used in the server.
-.sp
-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.
-.sp
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
-that this note was written cas is still buggy in memached. Turning on support
+that this note was written cas is still buggy in memached. Turning on tests
for it in libmemcached(3) is optional. Please see memcached_set() for
information on how to do this.
.sp
-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_cas_by_key() method behaves in a similar method as the non key
+methods. The difference is that it uses the group_key parameter to map
objects to particular servers.
.sp
-If you are looking for performance, memcached_set() with non\-blocking IO is
-the fastest way to store data on the server.
-.sp
-All of the above functions are supported with the \fBMEMCACHED_BEHAVIOR_USE_UDP\fPbehavior enabled. But when using these operations with this behavior on, there
+memcached_cas() is testsed with the \fBMEMCACHED_BEHAVIOR_USE_UDP\fPbehavior 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, \(ga\(ga MEMCACHED_BEHAVIOR_BINARY_PROTOCOL\(ga\(ga,
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
All methods return a value of type \fBmemcached_return_t\fP.
On success the value will be \fBMEMCACHED_SUCCESS\fP.
Use memcached_strerror() to translate this value to a printable string.
-.sp
-For memcached_replace() and memcached_add(), \fBMEMCACHED_NOTSTORED\fP is a
-legitmate error in the case of a collision.
.SH HOME
.sp
To find out more information please check:
-\fI\%https://launchpad.net/libmemcached\fP
-.SH AUTHOR
-.sp
-Brian Aker, <\fI\%brian@tangent.org\fP>
+\fI\%http://libmemcached.org/\fP
.SH SEE ALSO
.sp
-memcached(1) libmemached(3) memcached_strerror(3)
+memcached(1) libmemached(3) memcached_strerror(3) memcached_set(3) memcached_append(3) memcached_add(3) memcached_prepend(3) memcached_replace(3)
.SH AUTHOR
Brian Aker
.SH COPYRIGHT
-2011, Brian Aker
+2011, Brian Aker DataDifferential, http://datadifferential.com/
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