After some digging on the Internet, I've been unable to find a satisfying solution for my curiosity... Here's the thing : using a shell script, I've been able to obtain a list of IP addresses connected to my computer (ss), along with the names/PID of the applications (netstat -pn) listening for those connections (Skype, Chromium, and so on)
Once those applications have received data from a remote server, they "parse" it their way, and display it to me (HTML interpreted by the browser, conversations organised by the Skype client, ...), just as they should.
Here's where my curiosity comes in : I think it would be interesting to "eavesdrop" this data stream coming to the applications, in order to know how each of them communicates over the network (communication protocol, data structure, ...).
Do you know of any way there could be, to get an eye on this raw data, coming in to get processed by my applications ?