Mailing-List: contact cygwin-help AT sourceware DOT cygnus DOT com; run by ezmlm
List-Subscribe: <mailto:cygwin-subscribe AT sources DOT redhat DOT com>
List-Archive: <http://sources.redhat.com/ml/cygwin/>
List-Post: <mailto:cygwin AT sources DOT redhat DOT com>
List-Help: <mailto:cygwin-help AT sources DOT redhat DOT com>, <http://sources.redhat.com/ml/#faqs>
Sender: cygwin-owner AT sources DOT redhat DOT com
Delivered-To: mailing list cygwin AT sources DOT redhat DOT com
Message-ID: <549191FE7B71D311BC5900104B292132010E5084@kirk.takefive.co.at>
From: Martin Oberhuber <martin DOT oberhuber AT windriver DOT com>
To: "'cygwin AT sourceware DOT cygnus DOT com'" <cygwin AT sourceware DOT cygnus DOT com>
Subject: ash and bash: Backquotes don't work reliably on Windows 2000
Date: Wed, 20 Jun 2001 17:19:01 +0200
MIME-Version: 1.0
X-Mailer: Internet Mail Service (5.5.2653.19)
Content-Type: text/plain;
	charset="iso-8859-1"

Hello,

we have found out that on some Windows 2000 computers (particularly
very fast laptops with rather slow hard disk), the result of a command 
in backquotes isn't put into the variable associated reliably. A 
command like 

UNAME=`uname`

will return the correct result most of the time, but will sometimes 
return an EMPTY result! It looks like a race condition where the 
shell tries to read the program's output before the subprocess for
uname is finished... This is extremely annoying and makes it 
impossible to write reliable shellscripts!

The problem is very hard to reproduce. It seems to turn up only
on few computers, and only with lots of disk access around the
"backquote sections".

Is this problem already known, and what can we do to fix it?

I can try and put together a simple shellscript for reproducing
the problem, if needed.

Best regards,
Martin Oberhuber

--
---------------------------------/()\-----------------------------------
DI Martin Oberhuber                mailto:martin DOT oberhuber AT windriver DOT com
Senior Software Engineer           Phone  (UTC +1h): +43 (662) 457915-85
Wind River Systems (Salzburg) GmbH              Fax: +43 (662) 457915-6
Jakob-Haringer-Str.8, A-5020 Salzburg, Austria  http://www.windriver.com
----------------------- How Smart Things Think -------------------------
 

--
Want to unsubscribe from this list?
Check out: http://cygwin.com/ml/#unsubscribe-simple