[RFA/mingw32] environment variables are case-insensitive on win32

[Jerome Guitton]

Eli Zaretskii (eliz@gnu.org):

> Thanks.  But why did you exclude Cygwin?

Cygwin seems to be case-sensitive:

guitton@kerel ~
$ export FooBar=Bar

guitton@kerel ~
$ export FooBAR=BAR

guitton@kerel ~
$ echo $FooBar
Bar

guitton@kerel ~
$ echo $FooBAR
BAR


> > It would have been nice to have a configure test for that, using
> > setenv/getenv to detect the case insensitivity.  Unfortunately we
> > don't have setenv on win32. So I ended up using _WIN32 just like we do
> > to handle the .exe extension. Any other idea?
> 
> Use putenv?

I feel silly :)
I'll work on that.