If timeout is not NULL, it specifies a timeout period for the connection attempt. persistent indicates if the stream should be opened as a persistent stream.
php_stream_sock_open_unix() attempts to open the UNIX domain socket specified by path. pathlen specifies the length of path. If timeout is not NULL, it specifies a timeout period for the connection attempt. persistent indicates if the stream should be opened as a persistent stream. Generally speaking, this parameter will usually be 0.