How to tell emacs how to find TeX compiler?

Question

I am trying to compile a .tex file using AUCTeX on Emacs 27.2. When I run the LaTeX command (via the menu bar) I get the following message:

TeX-command: ERROR: AUCTeX cannot find a working TeX distribution. 
Make sure you have one and that TeX binaries are in PATH environment variable.
If you are using OS X El Capitan or later
remember to add /Library/TeX/texbin/ to your PATH

I have a file called TeX in /etc/paths.d which contains the line /Library/TeX/texbin. And if I open the .tex file with TeXShop it compiles fine. The start of the message file just to prove it:

This is pdfTeX, Version 3.141592653-2.6-1.40.22 (TeX Live 2021) (preloaded format=pdflatex)
 restricted \write18 enabled.
entering extended mode
(./Chapter1.tex

Any help greatly appreciated.

Answer 1

Ack! I found the answer in another thread, shortly after posting. See AUCTeX cannot find a working TeX distribution. In short, I needed to include the location of my texbin file my init.el. This is done with:

(setenv "PATH" (concat "/Library/TeX/texbin:"
                       (getenv "PATH")))
(add-to-list 'exec-path "/Library/TeX/texbin")

Everything works now. Leaving this here in case anyone else gets some benefit from it.