Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm
List-Subscribe: <mailto:cygwin-subscribe AT cygwin DOT com>
List-Archive: <http://sources.redhat.com/ml/cygwin/>
List-Post: <mailto:cygwin AT cygwin DOT com>
List-Help: <mailto:cygwin-help AT cygwin DOT com>, <http://sources.redhat.com/ml/#faqs>
Sender: cygwin-owner AT cygwin DOT com
Mail-Followup-To: cygwin AT cygwin DOT com
Delivered-To: mailing list cygwin AT cygwin DOT com
X-Injected-Via-Gmane: http://gmane.org/
To: cygwin AT cygwin DOT com
From: Sam Steingold <sds AT gnu DOT org>
Subject: Re: subprocess i/o interaction with shell (bash&cmd): shells
 compete for input with user program!
Date: 22 Jul 2003 12:23:18 -0400
Organization: disorganization
Lines: 41
Message-ID: <uvftu7cp5.fsf@gnu.org>
References: <uadb68wgz DOT fsf AT gnu DOT org> <20030722145702 DOT GA17342 AT redhat DOT com>
Reply-To: sds AT gnu DOT org
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
X-Complaints-To: usenet AT main DOT gmane DOT org
X-Attribution: Sam
X-Disclaimer: You should not expect anyone to agree with me.
User-Agent: Gnus/5.09 (Gnus v5.9.0) Emacs/21.3.50

> * In message <20030722145702 DOT GA17342 AT redhat DOT com>
> * On the subject of "Re: subprocess i/o interaction with shell (bash&cmd): shells compete for input with user program!"
> * Sent on Tue, 22 Jul 2003 10:57:02 -0400
> * Honorable Christopher Faylor <cgf-idd AT cygwin DOT com> writes:
>
> On Tue, Jul 22, 2003 at 10:30:52AM -0400, Sam Steingold wrote:
> >So, how can I exit driver and have the shell notice that its child
> >(driver) left a heir (runtime) and that the shell (bash & cmd) should
> >wait for runtime to finish.
> 
> You have two processes reading standard input at the same time?

yes, bash/cmd & runtime do read stdin simultaneously,
but I do NOT want that!

> The expected behavior in that situation is that it is unpredictable
> which process gets which keystroke.

yep.

> You want the parent of the parent of a process to know that there is a
> grandchild process sitting around waiting for input and have the
> grandparent (bash or cmd) wait for the grandchild to finish?

precisely!

> Under cygwin you'd accomplish this by having the parent process use
> one of the "exec" calls.

nope.  doesn't work either.
I get the same "input competition" when I use exec().

> There is no way to do what you want in a normal Windows program.

are you sure? :-(

-- 
Sam Steingold (http://www.podval.org/~sds) running w2k
<http://www.camera.org> <http://www.iris.org.il> <http://www.memri.org/>
<http://www.mideasttruth.com/> <http://www.palestine-central.com/links.html>
Daddy, why doesn't this magnet pick up this floppy disk?


--
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple
Problem reports:       http://cygwin.com/problems.html
Documentation:         http://cygwin.com/docs.html
FAQ:                   http://cygwin.com/faq/