can I use ddd for such a programm?

[Rosella Greco]

Hello everybody, 
        I would like to know if it possible to debug with ddd a programm I am
studying.
This program mainly does the following: it starts a daemon which is
waiting for a signal coming from an 'api'. the api is another executable
which simply send messages to the daemon. 
How can I open two instances of ddd which are 'listening to' aech other?
I hope to have been clear explaing my problem!
Thanks for any suggestions
Rosella