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

[Eli Zaretskii <eliz@gnu.org>]

> Date: Mon, 4 Apr 2016 01:38:52 +0900 (JST)
> From: Tino Calancha <f92capac@gmail.com>
> cc: Tino Calancha <f92capac@gmail.com>, 23206@debbugs.gnu.org
> 
> Let's assume COMMAND is "du -s"
> and LIST contains the dirs foo bar baz:
> foo is ~ Gb  with depth > 1
> and bar and baz are few kB dirs with depth 1.
> 
> The effective shell command to run is:
> du -s foo& du -s bar& du -s baz&
> 
> This creates a new process PROC in the system.
> PROC returns with the return code of the last command in the list
> (du -s baz):  this is a shell feature.
> The output from the remaining jobs is still comming to stdout,
> but is not associated to PROC, which already succeded.
> 
> With `dired-do-shell-command', we get all output only if foo
> is the last dir in LIST.
> 
> POSIX shells provide the builtin 'wait' to change this behaviour:
> it forces PROC to wait until all background jobs end.

Thanks.  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).

Can you modify the patch to do that?

Thanks.