[I don't know the exact luatex version, sorry]
Folks,
I get the very annoying and extremely unhelpful error message
```
Unable to read environment locale:exit now.
```
This is from a CI container where I can't easily call `locale` to find
out more details. Additionally, looking up this problem in the
internet, it seems that luatex is sensitive to very subtle details
that can easily be missed (for example, `-` vs. `_`).
Is there a way to make luatex tell me what exactly the problem is?
Werner
