in reply to Detect Open Proxies

Umm, i think that you can launch n threads (1 for each port to be 'scanned') and make your requests simultaneusly...

There are other similar post yet, maybe you can get some ideas from them: HTTP Proxy Detection and Proxy Detection In Perl.

Regards.

perl -Te 'print map { chr((ord)-((10,20,2,7)[$i++])) } split //,"turo"'