not the master key. MEMCACHED_FAILURE will be returned if no key is set. In the case
of a key which is too long MEMCACHED_BAD_KEY_PROVIDED will be returned.
+If you set a value with the value being NULL then the prefix key is disabled.
+
=item MEMCACHED_CALLBACK_USER_DATA
This allows you to store a pointer to a specifc piece of data. This can be
=head1 HOME
To find out more information please check:
-L<http://tangent.org/552/libmemcached.html>
+L<https://launchpad.net/libmemcached>
=head1 AUTHOR