This is the parent directory of the RtAudio distribution.  Here is a quick description of what is contained here:

RtAudio.h   - class header
RtAudio.cpp - class source
rtaudio.dsw - Visual C++ 6.0 workspace file

Directories:

tests - various test programs and Visual C++ 6.0 project files
doc   - complete documentation in a variety of formats (see doc/html/index.html)