Comments on 2019-11-04 Starting Emacs with custom configuration directory

perhaps I did not understand what you are trying to do but why do not use .emacs.d as a link whose destination you could change according the init process you need ?

– Anonymous 2019-11-06 07:50 UTC

That’s a nice idea, but what about a situation when you want to have two Emacs instances running at the same time: one “workhorse”, normal one and another, with a custom configuration directory?

Also, an environment variable has another advantage: you don’t have to remember to set it back to the normal setting.

– Marcin Borkowski 2019-11-06 17:21 UTC