PHP persistent socket connection

Question

I have the following architecture.

• A Windows application which can talk with external software through a defined port.
• A webapplication running on the same localhost.
• PHP-script serving as connector between these two sides.

I make from the webapplication AJAX-request to php-script which should make connection with the windows application and sent to the webapplication its response.

It works nice. But only one time. The second call to php-script already doesn't work because the window application deny access to php-script. I tryed to use pfsockopen so:

if(!isset($fp)) {
    $fp = pfsockopen($address, $service_port, $errno, $errstr, 30);    
}
if(!$fp) die($errstr);

fwrite($fp, $out);

But window application deny it when I call it second time. What should be the right approach/solution?

Something like let php script runs as a server keeping connection? Do you have an idea or example? Thank you.

Answer 1

To me it seems like after first time of successful connection you are trying to connect your windows application on same port. Are you changing port number? If you create a persistent connection its likely that windows will keep that port assigned to your first connection. Then it can't use same port for a while. And this explains why it works first time try but not after. Try to use fsockopen instead of persistent one.