SoX send and receive buffer

I have integrated SoX (Sound eXchange) source code into another software which works fine, I have it open a wav file, process it and save to an output file, which the rest of the software then uses.

Instead of opening a file, I need the SoX source code to read/write from/to variables. The example1.c from the SoX source code says that "in this example, we get samples to process from a SoX-openned audio file. In a different application, they might be generated or come from a different part of the application".

It doesn't explicitly say how to do this so I'm looking to the gurus here to show me the light.

Any feedback is appreciated. Also let me know if you need more info to assess the problem.

JP