[ESS] How to get working Rnw file name inside script

[Susumu Tanimura]

Dear all,

When using the Stangle() function within an Rnw file to insert an
entire R code into an appendix of a document, it is necessary to
provide the working Rnw file name. While manually entering the name is
a viable option, it would be beneficial for me to implement it within a
template for Rnw files. 

My question is how to get working Rnw file name inside script.

This issue is not directly related to ESS, but the solution must be
compatible with ESS and Emacs.

Thank you

-- 
Susumu Tanimura