(PHP 4, PHP 5)
session_name — Get and/or set the current session name
session_name() returns the name of the current session. If name is given, session_name() will update the session name and return the old session name.
The session name is reset to the default value stored in session.name at request startup time. Thus, you need to call session_name() for every request (and before session_start() or session_register() are called).
The session name references the name of the session, which is used in cookies and URLs (e.g. PHPSESSID). It should contain only alphanumeric characters; it should be short and descriptive (i.e. for users with enabled cookie warnings). If name is specified, the name of the current session is changed to its value.
The session name can't consist of digits only, at least one letter must be present. Otherwise a new session id is generated every time.
Returns the name of the current session.
Example #1 session_name() example
/* set the session name to WebsiteID */
$previous_name = session_name("WebsiteID");
echo "The previous session name was $previous_name<br />";