[PD-dev] Messaging between Pd and GUI

[Tarakajian, Samuel]

Hi everyone,
So I trying to develop what amounts to a new implementation of the Pd GUI.  The first step was of course to remove the old GUI, which is actually a lot simpler than I thought.  Pd can actually be launched with a -nogui flag, which keeps the gui from opening.  Even more excellently, Pd can be launched with the guiport flag, which tells Pd to listen for input from a GUI outputting to the specified socket. 

The problem is that I have no idea where to get started on learning how Pd communicates with the GUI.  All I know is that messages are sent back and forth over a socket, typically 5400.  The source code is fairly impenetrable; what would really be nice is if someone could point me towards what I need to look at to figure out how the Pd-GUI message system works.  If there is a guide, or if someone could tell me where to focus my attack on the source code, that would be great.

Thanks very much,
Sam