I am trying to build a code base that works on both the Arduino IDE (and Visual Micro - an Arduino plugin for Visual Studio) and Atmel Studio. Some code will be specific to Arduino but most of the code is reusable in both environments.
I am having trouble with selecting the correct header files that will be recognized in both IDEs.
For instance when I wrote some code in Atmel Studio the 'NULL' is defined in stddef.h. But in the Arduino IDE that header file is not found (actually I tested that with Visual Micro).
So what is the best approach? Should I make my own header file that I use in all my code and have two versions of that (one for Arduino and one for Atmel Studio)?
Or are there other (better?) options?