How do I test if R is running as Rscript?

Question

I have code in a single R file that I want to be able to source (i.e., to define my functions etc.) within RStudio during development, and also run using the #! /usr/b

Answer 1

You could use interactive to test if R is running in interactive mode. interactive will return FALSE under Rscript and TRUE under (most?) GUIs.