X-Recipient: archive-cygwin AT delorie DOT com
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 475EC385041D
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cygwin.com;
	s=default; t=1610348512;
	bh=9WDlP0NvvFrLG8/JXrbwkVCpwTiu3wpLQev8Rw+QnPE=;
	h=Subject:To:References:Date:In-Reply-To:List-Id:List-Unsubscribe:
	 List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To:
	 From;
	b=yl4zOrbOyjokooW7HFvO/1ngjRy8MIJH+nyNMHXWnWr0xzWfKNPb24AnrwYnOWouw
	 IvPktfUiPKGRDSROEnPPSclJhN7DuCR/bMhlkYB8NIDTIx+Su+3DSlbzLrvTEY0mO0
	 R8pFkgh5F1USBlevM5b/5vnbxWphEaKq0eLc38Eg=
X-Original-To: cygwin AT cygwin DOT com
Delivered-To: cygwin AT cygwin DOT com
DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 4A84B386102D
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
 d=1e100.net; s=20161025;
 h=x-gm-message-state:subject:to:references:from:message-id:date
 :user-agent:mime-version:in-reply-to:content-language
 :content-transfer-encoding;
 bh=2OCj+Xh29VuunvjdxaqnNXzFrvnTlwNMbDldYCVZztU=;
 b=NAJvZ0Pib24XmPke2oCzGdrCAvM0zJRL9GRhJ1qs8ivjf3Oebi4mIqWTbzPmyj5JXy
 YLrdXihfOBWevWJ4SEorua+kLOvzChfjfGw36CHr/mRfzE3rDS0UpdJx8JD+Q5bhvIU5
 Py6C/aAKy7DcMnd6V+OP+S3+MOrjKAo7ro/D8HQpPcSAqg0X1bKuys5b9xbJcAE8Dil/
 B76Ephr2bmQ3zQJMnzYRgueE+LFE6+Cu5tVPyvX5TljsHX+wHZwVW+j1F8JKf95v+slS
 RFbjBlup3iqxMBM4bSGyZoBbu7SWRtradRhuNinRXZGh/ros2ZqRYZiEmrK9Fpc0DeBn
 Q0lw==
X-Gm-Message-State: AOAM532wO48EnRO2g5RcVAL1lLfEyqvLK1nvMXUBtr2NfOF65ESbiba5
 5vpck0Li7tJ9Phnsod6M9EyKNELUR20=
X-Google-Smtp-Source: ABdhPJylJ7g1fRjgTD6HDmF8jDmj28gwnnGtXauZQ+y+9h+plwaP2ZO8RdavTWqJLmVNb6Cg5cBqvg==
X-Received: by 2002:a5d:4d8d:: with SMTP id b13mr14251708wru.415.1610348508320; 
 Sun, 10 Jan 2021 23:01:48 -0800 (PST)
Subject: Re: PTHREAD_PROCESS_SHARED not implemented (was PTHREAD_MUTEX_SHARED
 on Cygwin)
To: cygwin AT cygwin DOT com, Brian Inglis <Brian DOT Inglis AT SystematicSw DOT ab DOT ca>
References: <657c8576-2715-8c80-a59a-23453306230f AT netcologne DOT de>
 <32467133-a288-b974-4a86-fe17d1ac6a14 AT SystematicSw DOT ab DOT ca>
 <c53fa5c5-84f9-dc0d-0be5-e7602f8bc314 AT SystematicSw DOT ab DOT ca>
Message-ID: <1cd19914-1fcf-99ce-8ea5-bdcfb64998c1@gmail.com>
Date: Mon, 11 Jan 2021 09:01:42 +0200
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101
 Thunderbird/78.6.0
MIME-Version: 1.0
In-Reply-To: <c53fa5c5-84f9-dc0d-0be5-e7602f8bc314@SystematicSw.ab.ca>
Content-Language: en-GB
X-Spam-Status: No, score=-1.6 required=5.0 tests=BAYES_00, DKIM_SIGNED,
 DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, FREEMAIL_FROM, NICE_REPLY_A,
 RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS,
 TXREP autolearn=ham autolearn_force=no version=3.4.2
X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on
 server2.sourceware.org
X-BeenThere: cygwin AT cygwin DOT com
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: General Cygwin discussions and problem reports <cygwin.cygwin.com>
List-Unsubscribe: <https://cygwin.com/mailman/options/cygwin>,
 <mailto:cygwin-request AT cygwin DOT com?subject=unsubscribe>
List-Archive: <https://cygwin.com/pipermail/cygwin/>
List-Post: <mailto:cygwin AT cygwin DOT com>
List-Help: <mailto:cygwin-request AT cygwin DOT com?subject=help>
List-Subscribe: <https://cygwin.com/mailman/listinfo/cygwin>,
 <mailto:cygwin-request AT cygwin DOT com?subject=subscribe>
From: Noel Grandin via Cygwin <cygwin AT cygwin DOT com>
Reply-To: Noel Grandin <noelgrandin AT gmail DOT com>
Content-Transfer-Encoding: 7bit
Content-Type: text/plain; charset="us-ascii"; Format="flowed"
Errors-To: cygwin-bounces AT cygwin DOT com
Sender: "Cygwin" <cygwin-bounces AT cygwin DOT com>



On 2021/01/10 12:16 am, Brian Inglis wrote:
> 
> For more about Windows limitations and alternatives see:
> 
> https://www.boost.org/doc/libs/1_75_0/doc/html/interprocess/sharedmemorybetweenprocesses.html#interprocess.sharedmemorybetweenprocesses.sharedmemory.emulation 
> 

For the specific case of inter-process mutexes, Windows already supports multiple processes accessing the same mutex:

https://docs.microsoft.com/en-us/windows/win32/sync/interprocess-synchronization

But presumably there would need to be a lot of bookkeeping by cygwin/newlib to provide POSIX semantics on top of that.
--
Problem reports:      https://cygwin.com/problems.html
FAQ:                  https://cygwin.com/faq/
Documentation:        https://cygwin.com/docs.html
Unsubscribe info:     https://cygwin.com/ml/#unsubscribe-simple