Sweave doesn't seem to get .Rnw file encoding right

Question

This question arose out of the following question on tex.sx: Sweave generating invalid LaTeX. The problem seems to be that Sweave is not recognizing the encodin

Answer 1

Potential fix:

Try putting

export LANG=en_US.UTF-8

in your TeXShop script.

(Original idea was in the ~/.bashrc file, but apparently TeXShop doesn't load that.)

EARLIER:

What happens when you put sessionInfo() in the Rnw file?

\documentclass{article}
\usepackage[utf8]{inputenc}
\begin{document}
Some non-ascii text: éüáî
<<>>=
sessionInfo()
@ 
\end{document}