Memcached::casByKey
Compare and swap an item on a specific server
Description
public bool Memcached::casByKey
( float $cas_token
, string $server_key
, string $key
, mixed $value
[, int $expiration
] )
Parameters
-
cas_token
-
Unique value associated with the existing item. Generated by memcache.
-
server_key
-
The 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.
-
key
-
The key under which to store the value.
-
value
-
The value to store.
-
expiration
-
The expiration time, defaults to 0. See Expiration Times for more info.
Return Values
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.