bug#19350: #19350 24.4; Incorrect quoting of %-signs for Windows command shell

[Eli Zaretskii]

> From: Noam Postavsky <npostavs@users.sourceforge.net>
> Date: Thu, 18 Aug 2016 08:07:41 -0400
> Cc: Eli Zaretskii <eliz@gnu.org>, 19350@debbugs.gnu.org
> 
> On Wed, Aug 17, 2016 at 10:02 PM, Demi Obenour <demiobenour@gmail.com> wrote:
> > But *nix has no such feature [environment variables affect shell escaping], 
> > nor the associated gotcha.
> 
> I'm not sure what you're trying to point out here. Why does that
> matter? We're talking about Windows, not *nix.

Indeed.  When I wrote "as shell prompt" I meant the Windows shell, not
the Unix shell.  Emacs tries to hide the OS idiosyncrasies as much as
it can, but that's not possible everywhere.