pcap - streaming and receiving udp in the same computer

To explain what I would like to get, here's an example. Let's say, we have a PC with one NIC. It has single IP address 172.16.0.1. Using VLC, we start a udp stream to 172.16.0.1:1234, then launch another copy of VLC and connect to udp://@172.16.0.1:1234. Now we'll see our video streaming.

If you run sniffer, you will see packets from 172.16.0.1:some_random_port to 172.16.0.1:1234 on loopback. There's no trafic on our NIC.

What I want to do is to stream and rece开发者_开发知识库ive udp in the same computer, like VLC does it. But the main problem is that pcap can only pcap_open() a real device, it can't work with loopback.

Is it possible to solve that problem?

P.S. I'm using Windows and WinPcap, unlike Linux version, it can send packets.

If you just want to send and receive UDP packets, I would suggest just using regular Winsock sockets, just as you'd use regular sockets on UN*X; using WinPcap requires that you re-implement IP and UDP, and won't let you send to another socket on the same machine under Windows (or on at least some versions of UN*X, either).

If you want to watch the traffic you're sending, unfortunately WinPcap won't help, as it relies on packets being sent out and received from NDIS (its driver plugs into NDIS), and that doesn't happen for packets sent from one socket on a machine to another socket on the same machine.

(Note, BTW, that libpcap can send packets on Linux and *BSD and Mac OS X and Solaris and Digital/Tru64 UNIX, for example, and has been able to do so for several years; older versions of libpcap didn't support it, but the versions available for the past few years can. However, as per my first paragraph, it would not make sense to use libpcap to send and receive regular UDP packets on those OSes, just as it makes no sense to use WinPcap for that purpose on Windows.)