Thanks a lot. It means I can access flash cookie as js/php cookie. Am I right?
No. That code is for a PHP cookie. It might not be a PHP cookie specifically, but a webserver (http?) cookie.
I don't know if you can create a Flash cookie and read it with another language. I know that Flash cookies are stored in the filesystem (in a different place to web cookies) and so they may be unreachable by the browser and the webserver.
Maybe it will be easier to have Flash call a PHP script to create the cookie and another PHP script to read it?