portscan a simple portscanner online with Winfy

We have hosted the application portscan a simple portscanner in order to run this application in our online workstations with Wine or directly.

Quick description about portscan a simple portscanner:

Portscan is a simple TCP port scanner (connect scan, similar to nmap -sC).
It is implemented with threads for better speed.
Please see the code and review it. Criticism is more than welcome.
Helps needed to make it robust.

Audience: Developers.
User interface: Command-line.
Programming Language: C.

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