Is it possible to communicate with the pd soundserver as like the server of supercollider (per OSC for instance)?, so without doing things in pd directly but from another programming langauge?

@amirt I cannot think of a reason not to use Pd as a sound server. You can communicate using the OSC format through [netsend] and [netreceive] and the OSC tools [oscformat] and [oscparse].
There are tools in the "ggee" and "ext13" libraries for streaming audio as well, but I don't know if they have been updated for 64-bit Pd for any OS.
They were included in the "extended" version of Pd and might be available through Deken in Pd Vanilla.
You might not need to stream audio across the network though?
The "maxlib" library had a [netserver] object as well, which would wait for clients, but again it was included in extended and might not be available for vanilla.

The "bin" folder of Pd also contains executables....... pdsend and pdreceive.... that can be called from within other programs such as python.
Example....... https://guitarextended.wordpress.com/2012/11/03/make-python-and-pure-data-communicate-on-the-raspberry-pi/

Lastly, VST's can be run in Pd, and Pd can be run as a VST, and there are some libraries for running Pd to a limited extent within a web server, or an Android or iOS app.
David.