(PHP 5 >= 5.4.0)
SessionHandlerInterface::open — Initialize session
$save_path
, string $name
)Re-initialize existing session, or creates a new one. Called when a session starts or when session_start() is invoked.
save_path
The path where to store/retrieve the session.
name
The session name.
会话存储的返回值（通常成功返回 0，失败返回 1）。