Caches a variable in the data store, only if it's not already stored.
Note:
Unlike many other mechanisms in PHP, variables stored using
apc_add() will persist between requests (until the
value is removed from the cache).
Parameters
key
Store the variable using this name. key
s are
cache-unique, so attempting to use apc_add() to
store data with a key that already exists will not overwrite the
existing data, and will instead return FALSE. (This is the only
difference between apc_add() and
apc_store().)
var
The variable to store
ttl
Time To Live; store var
in the cache for
ttl
seconds. After the
ttl
has passed, the stored variable will be
expunged from the cache (on the next request). If no ttl
is supplied (or if the ttl
is
0), the value will persist until it is removed from
the cache manually, or otherwise fails to exist in the cache (clear,
restart, etc.).