X-Spam-Check-By:	sourceware.org
From:	"Dave Korn" <dave DOT korn AT artimi DOT com>
To:	<cygwin AT cygwin DOT com>
Subject:	RE: Inter-Process Mutexes
Date:	Wed, 6 Sep 2006 11:26:57 +0100
Message-ID:	<00c701c6d19e$fb2d0f30$a501a8c0@CAM.ARTIMI.COM>
MIME-Version:	1.0
X-Mailer:	Microsoft Office Outlook 11
In-Reply-To:	<20060904082849.GB4461@implementation.labri.fr>
Mailing-List:	contact cygwin-help AT cygwin DOT com; run by ezmlm
List-Unsubscribe:	<mailto:cygwin-unsubscribe-archive-cygwin=delorie DOT com AT cygwin DOT com>
List-Subscribe:	<mailto:cygwin-subscribe AT cygwin DOT com>
List-Archive:	<http://sourceware.org/ml/cygwin/>
List-Post:	<mailto:cygwin AT cygwin DOT com>
List-Help:	<mailto:cygwin-help AT cygwin DOT com>, <http://sourceware.org/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-MIME-Autoconverted:	from quoted-printable to 8bit by delorie.com id k86ARAhC023847

On 06 September 2006 10:58, Samuel Thibault wrote:

> Hi,
> 
> Drake Baker, le Mon 04 Sep 2006 01:49:25 -0500, a  crit :
>> I have seen conflicting information on the web concerning inter-process
>> mutexes in CYGWIN.  I have seen outright statements that it is not
>> supported, and I have seen statements that ALL mutexes are inter-process by
>> default.  Obviously, only one statement is currently correct.
> 
> Both are true :)
> 
> Windows provides inter-process mutexes (you just need to give a name to
> CreateMutex ; every process that give the same name will get the same
> mutex).  But cygwin doesn't provide a pthread interface for it.  PTW.

  The underlying pthread implementation uses win32 CreateSemaphore, as it happens.  See pthread_mutex::pthread_mutex in thread.cc.  The pthread functions are not supposed to be inter-process, they are within-process only.  As Václav pointed out, the answer is to set CYGWIN=server in the environment and use the SysV IPC functions.


    cheers,
      DaveK
-- 
Can't think of a witty .sigline today....


--
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/

- Raw text -