bug#23206: 25.0.92; dired-shell-stuff-it: wait until all parallel jobs finish

[Eli Zaretskii <eliz@gnu.org>]

> Date: Tue, 5 Apr 2016 14:24:41 +0900 (JST)
> From: Tino Calancha <f92capac@gmail.com>
> cc: Tino Calancha <f92capac@gmail.com>, 23206@debbugs.gnu.org
> 
> >This means the fix should only affect systems with a Posix
> >shell.
> >The stock MS-Windows shells don't have a 'wait' command (and
> >don't need this fix in the first place, as the problem doesn't exist
> >on MS-Windows, AFAICS).
> I see.  Thank you.
> I rewrote the patch so that it adds 'wait' when 'system-type' is
> not in '(ms-dos windows-nt).

Thanks.

I have one more nit:

> * lisp/dired-aux.el (dired-shell-stuff-it):
> Drop all trailing ';' and '&' in command;
> change indentation with \t to ?\s;

These are unrelated changes, so please don't mix them with the changes
that really fix the problem at hand.  In particular, removing all the
trailing ';' and '&' characters might cause bugs, because the code you
are modifying doesn't really understand what the shell command is
about, so it might inadvertently delete characters that are there for
a reason.  It is up to the user to type a correct command, and Emacs
shouldn't try second-guessing those commands.  So let's only remove a
single instance of these characters at the end, as the original code
did.

Thanks.