Checking a port if it's in use/open

[prof.ebral]

You're welcome, Sutee. I don't expect you to use the softwares themselves, instead I thought you would be able to draw some information from them. They are not my softwares so I can verify the claims either. I hope you get what you are looking for.

Some extra info: Firewall Builder is a Qt program that helps you write iptable/netfiler rules. As such it's only for Linux and MacOSX http://www.fwbuilder.org/
But I did some extra research and found an open source Firewall for Windows called Netdefender. This has a Port scanner to scan for open ports: http://www.programmerworld.net/personal/firewall.htm This one is in Visual C++.

Again same premise, draw from it what you can to get what you really want.

[squidge]

After your replies in this forum, I really expected more than the posting of a quick google search. Pointing to the sourcecode of an open-source firewall is hardly practical either, specially considering it is written in Visual C++ and MFC when they were asking for Qt solution. I fail to see why you posted the other links, since they clearly do even less of what was asked.

[wysota]

@fatjuicymole:

Leave them alone, it seems they perfectly know what they want and what they are doing. At some point we have to admit we are just trolling around on this forum and bow our heads before a solution for detecting which tcp (won't work for udp) ports are open by trying to register a listening socket on each and every one of them. Let's face it - resistance is futile and even running a level three diagnostic wouldn't help.

[JD2000]

If you literally wish to see if a port is in use/open then the netstat command is probably what you need.

Variations are built into the kernels of most operating systems.


If you really want to build your own then something based around the pcap library or similar is what you need.

Personally, I would not go there but good luck!

[sutee84]

I solved the problem, I check the log file, it was the easier way.