Re: Emacs 25.2, win64, env vars

[Eli Zaretskii <eliz@gnu.org>]

> From: Fabrice Popineau <fabrice.popineau@gmail.com>
> Date: Mon, 24 Jul 2017 22:34:20 +0200
> Cc: Noam Postavsky <npostavs@users.sourceforge.net>, Emacs developers <emacs-devel@gnu.org>
> 
>  So you are saying that MSYS holds two separate environment variables,
>  one called "temp", the other "TEMP"? If so, what do native Windows
>  programs started from such a shell get in their environment? The
>  upper-case one? the first one in the order? both? something else?
> 
> Both GetEnvironmentVariable) and getenv() return :
> 
> TEMP=C:\MSys64\tmpy
> temp=C:\MSys64\tmp
> 
> And from the shell :
> 
> $ echo $TEMP
> /tmp
> 
> $ echo $temp
> C:\Users\Fabrice\AppData\Roaming\Local\Temp
> 
> So they return the win32 path from the value of the upper case variable.

Maybe we could remove the lower-case variant at startup, so that it
won't get in the way of programs Emacs invokes?  Or could that break
some use cases for people who also set their shell in Emacs to the
MSYS shell?

> My opinion (but I may well be alone) is that Emacs/win32 fiddles too much with those unix-like environments.
> This works most of the time, but it also sometimes creates surprising situations.

Environment variables are not limited to Unix, so I'm not sure why you
think it's Unix-like.