bool scache_connect(string id [, string host [, string secret [, long port ]]])
bool scache_connect(string id [, string host [, string secret [, long port ]]])

scache_connect and scache_pconnect prepares and opens socket level connection to scached backend but doesn't query anything. These functions should be considered as default connection methods to be used. Since these functions doesn't query anything, actual result for session availability occurs delayed when first round trip query is invoked. scache_pconnect reuses existing connections even they might be opened from completely different application. scache_connect instead opens new connection every time.

id is in most cases the cookie or whatever you send to browsers to distinguish them between. secret is meant to be web application specific check to be matched on a case where same scached is used between not so trustworthy apps and servers. If secret is set it must match on further opens. On a simple local-only scacheds secret has no sensible uses.

scache_open, scache_reset and scache_connect are all for opening session handle. Differencies between them are :

On class interface there is no connect-method. Constructing SCache object is equivalent to scache_(p)connect -functions.


Unique session identifier that distinguishes sessions from each other on scached. Basically this is the cookie or whatever you use to distinguish your users. Scache treats this as null terminated c-string so it is not binary safe.
Host name of server to connect. If host name begins with slash (/) it is treated as a unix socket path to local filesystem. If hostname is null, system default path or ini-overrided value is used.
Secret to match on already existing session or to be set to a new session. Scache treats this as null terminated c-string meaning it is not binary safe.
Maximum idle time in seconds of created session between queries. If expire time is exceeded, session is invalidated in complete. If expire is false, either system default or it's ini overrided value is used.
TCP-port of host to connect. If port is false, either system default or it's ini overriden value is used.
Something not to be used.

Return values

Session resource on success, FALSE on failure. All other functions operate on this returned resource as their first parameter.


On a normal life-cycle you should separate user login from other activities and create session on that login phase with either scache_open or scache_reset. With scache_open you can detect already existing session and choose to select another session identifier while scache_reset always resets session leaving undetectable possibility there is another user using same identifier. It's a case how much you trust you id's uniqueness.

On the later page loads you should acquire session resource with scache_connect to avoid unnecessary backend queries. Good practice is to separate session initialization from it's further use.

Finally you log out the user by destroying session with scache_drop

In most cases session conversation with scached backend begins in page processing by connecting to scached backend with scache_pconnect and querying certain general session values from backend for example with scache_iov. In this default construction you should check result value from that first query wheter it fails and result value returned by scache_lasterr is SCERR_NO_SESSION to detect failed or unavailable session.


$my_session_identifier = $_COOKIE['MySessionIdentifier'];
$session = scache_pconnect($my_session_identifier);