-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).
-.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 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 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 testsed with the \fBMEMCACHED_BEHAVIOR_USE_UDP\fPbehavior enabled. But 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
+\fI\%memcached_prepend()\fP 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.
+.sp
+\fI\%memcached_prepend()\fP places a segment of data before the last piece
+of data stored. Currently expiration and key are not used in the server.
+.sp
+\fI\%memcached_append()\fP 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
+\fI\%memcached_prepend_by_key()\fP and
+\fI\%memcached_append_by_key()\fP 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.
+.sp
+If you are looking for performance, \fBmemcached_set()\fP with non\-blocking
+IO is the fastest way to store data on the server.
+.sp
+All of the above functions are testsed with the
+\fBMEMCACHED_BEHAVIOR_USE_UDP\fP 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