(PECL memcached >= 0.1.0)
Memcached::casByKey — Compare and swap an item on a specific server
$cas_token
, string $server_key
, string $key
, mixed $value
[, int $expiration
] )
Memcached::casByKey() is functionally equivalent to
Memcached::cas(), except that the free-form
server_key can be used to map the
key to a specific server. This is useful if you need
to keep a bunch of related keys on a certain server.
cas_tokenUnique value associated with the existing item. Generated by memcache.
server_keyThe key identifying the server to store the value on or retrieve it from. Instead of hashing on the actual key for the item, we hash on the server key when deciding which memcached server to talk to. This allows related items to be grouped together on a single server for efficiency with multi operations.
keyThe key under which to store the value.
valueThe value to store.
expirationThe expiration time, defaults to 0. See Expiration Times for more info.
Returns TRUE on success or FALSE on failure.
The Memcached::getResultCode() will return
Memcached::RES_DATA_EXISTS if the item you are trying
to store has been modified since you last fetched it.