This is my first post and I have been experimenting with an rtl-sdr for only a few weeks.  So I am sure I am not doing a lot of things correctly.  But:

I have created a GRC flow graph that does what I want.   It has a rtl-sdr>FIR filter> I/Q samples> file.
I need to create a stand alone program that when run, implements the same functions but rather then sending the samples to a file, passes them to my program for further processing.

I intend to run it on a Raspberry Pi so the less overhead the better.

Thanks In Advance.

Pete