Rationale for setting LC_ALL

[nthiery]

Dear micromamba docker image devs,

The micromamba docker images sets both LANG and LC_ALL to C.UTF-8. My reading of the gettext manual is that the recommendation would be to only set LANG, and not LC_ALL, to let users specify their locale with LANG:

• "LANG is the normal environment variable for specifying a locale"
• "LC_ALL takes precedence over LC_ALL"
• "Some systems, unfortunately, set LC_ALL ..."

Is there some specific rationale for setting LC_ALL in the context of this docker image?

Caveat: my use case (building docker images to run jupyter based interactive services) may be quite different from other use cases (e.g. running in a CI).

Thanks!

[wholtz]

Hello @nthiery - Looking back through git blame, that line originally went in 5 years ago.

Setting both LANG and LC_ALL been common in python and conda docker images since 2014. There were problems with character handling pre-python 3.7 that were mitigated by setting both LANG and LC_ALL. These issues were addressed in python
3.7 via PEP 540 and PEP 583.

Because users could install conda environments that require python 3.6, it can still be useful to have both LANG and LC_ALL set.

Are you not able to override these environment variables in your downstream dockerfile or docker run -e ....?