Communicating with Pure Data in C

Question

I'm looking for a way to be able to communicate with a Pure Data patch via C programming - I suppose this is different from writing an external in C which involves writing patches themselves. I only need to communicate and make changes in existing patches. For instance, in the patch shown in the image:

I need to find a way to change the delay parameters programmatically, in the case of the three objects delwrite~, *~, and delread~. I wish to write a simple C program that communicates with Pure Data, loads the patch and makes the required changes. Any insights would be appreciated.

is that "C-program" running within the address-space of Pd or as a separate process? — umläute, Apr 12 '16 at 08:48
Ideally I would want to run it as a separate process rather than using an external — Abhishek Tirkey, Apr 12 '16 at 21:21

umläute · Accepted Answer · 2022-01-13T08:14:57.727

there are numerous ways to communicate with a running Pd instance.

The most straightforward one is to use network communication:

[netreceive] allows you to receive messages from another process, using the FUDI protocol. The following patch listens on UDP/9999 for incoming messages:

network controlled feedback patch

on the C-side, just create a normal UDP-socket and send the data to localhost:9999 (assuming your process runs on the same machine).

Alternative methods include using libpd, which is a library version of Pd and allows you to load Pd-patches directly in your program.

Communicating with Pure Data in C

1 Answers1