Need the filename of the Rnw when knitr runs in rStudio

Question

When working on a reproducible research project, I would like to know the name of the Rnw file that is being run to use as an R variable.

This would be analogous to

Answer 1

You can use the following two idioms to fetch the directory and name of the current file in knitr:

knitr:::.knitEnv$input.dir
knitr:::knit_concord$get("infile")

This is independent of RStudio, the knitr package is entirely responsible for this. These are private functions and variables that can change at any time without notice, so if you need something reliable, you might want to file an issue on GitHub.

Answer 2

knitr now has a method for this: current_input()

https://github.com/yihui/knitr/issues/701