Bottom Line: sources and headers that are still changing go in /src. Code that has crystallised should go in /lib & /include (actually you could keep all .libs and their .hs in /lib).
- Keep own sources and headers together, provided they are (a) specific to this project or (b) have not yet been factored out as a shared library.
- Once certain sources in the main project have been factored out as a (relatively stable) library, place the
.a or .lib into /lib, and its public interface header into /include.
- All third party libraries and their public interface headers also go into
/lib & /include.
As others note, it is often more compatible for tools / IDEs to access .h/.c from one folder. But from an organisational view it can be useful to separate changing local code from stable lib code.
