X-Recipient:	archive-cygwin AT delorie DOT com
DKIM-Filter:	OpenDKIM Filter v2.11.0 sourceware.org 3ABF1385771D
DKIM-Signature:	v=1; a=rsa-sha256; c=relaxed/relaxed; d=cygwin.com;
	s=default; t=1682016068;
	bh=8AElkN1nBWLFwKmpvN8o8QKcbeDF2jtNloLPtfTOrZo=;
	h=Date:To:Cc:Subject:References:In-Reply-To:List-Id:
	List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe:
	From:Reply-To:From;
	b=oyWrgdv2VcxQf+KjTppQn6i8tIBFyriEPPj8I7MHnVZKp6TAMhxrbstQz+EdNM/5H
	6XzzV6lDx9zsGy4fVEyCBlq7wyIwWujHUn7TR7xjuaj0iRxFAVB9iRvBu06A0aH92t
	dnHjEkxHZ4wpZMNFxyjiRVYmV97dwElupfQxopLI=
X-Original-To:	cygwin AT cygwin DOT com
Delivered-To:	cygwin AT cygwin DOT com
DMARC-Filter:	OpenDMARC Filter v1.4.2 sourceware.org 3BCFD3858D37
X-Spam-Checker-Version:	SpamAssassin 3.4.6 (2021-04-09) on
	server2.sourceware.org
X-Spam-Language:	en
X-Spam-Relay-Country:
X-Spam-DCC:	B=MGTINTERNET; R=smtp1.atof.net 1170; Body=1 Fuz1=1 Fuz2=1
X-Spam-RBL:
X-Spam-PYZOR:	Reported 0 times.
Date:	Thu, 20 Apr 2023 14:40:23 -0400
To:	Bruno Haible <bruno AT clisp DOT org>
Cc:	cygwin AT cygwin DOT com
Subject:	Re: posix_spawn facility
Message-ID:	<ZEGHF4jr9PaV0E88@xps13>
References:	<1752276 DOT 7aRn1RRit1 AT nimes> <ZEFKW/rbAS8x4QbV AT calimero DOT vinschen DOT de>
	<ZEFO9ELNzIliSGPv AT calimero DOT vinschen DOT de> <4892432 DOT 0VBMTVartN AT nimes>
MIME-Version:	1.0
In-Reply-To:	<4892432.0VBMTVartN@nimes>
X-Spam-Status:	No, score=-2.1 required=5.0 tests=BAYES_00, KAM_DMARC_STATUS,
	SPF_HELO_NONE, SPF_PASS, TXREP,
	T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6
X-BeenThere:	cygwin AT cygwin DOT com
X-Mailman-Version:	2.1.29
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:	"gs-cygwin.com--- via Cygwin" <cygwin AT cygwin DOT com>
Reply-To:	gs-cygwin DOT com AT gluelogic DOT com
Errors-To:	cygwin-bounces+archive-cygwin=delorie DOT com AT cygwin DOT com
Sender:	"Cygwin" <cygwin-bounces+archive-cygwin=delorie DOT com AT cygwin DOT com>
X-MIME-Autoconverted:	from base64 to 8bit by delorie.com id 33KIfVxq006500

On Thu, Apr 20, 2023 at 04:58:20PM +0200, Bruno Haible via Cygwin wrote:
> Corinna Vinschen wrote:
> > > Hmm.  Your code uses lpReserved2 for that, but the functionality is
> > > one implemented in MSVCRT.  For obvious reasons, Cygwin executables
> > > are not linked against msvcrt.dll and we're using lpReserved2 for our
> > > own purposes.
> > 
> > Oh, btw., did you know that there's a newer mechanism for defining
> > specific inheritable handles to CreateProcess, which is implemented
> > in kernel32.dll, so it does not depend on MSVCRT?
> > 
> > There's a STARTUPINFOEX structure which allows to specify the 
> > additional handles.  See
> > 
> > https://learn.microsoft.com/en-us/windows/win32/api/winbase/ns-winbase-startupinfoexa
> > 
> > and the PROC_THREAD_ATTRIBUTE_HANDLE_LIST argument described in
> > 
> > https://learn.microsoft.com/en-us/windows/win32/api/processthreadsapi/nf-processthreadsapi-updateprocthreadattribute
> 
> Indeed, this appears to be a more "official" way to pass handles for fd ≥ 3,
> instead of lpReserved2 — albeit without associated 'flags'. Not sure how
> O_APPEND is handled then... (Note: O_APPEND behaviour is tested by
> gnulib/tests/test-posix_spawn-open2.c.)
> 
> I had seen this doc page, but thought it was irrelevant because the
> title is about "thread attributes", not "process attributes"...

Excellent (very technical) article on the subject:

Programmatically controlling which handles are inherited by new processes in Win32
https://devblogs.microsoft.com/oldnewthing/20111216-00/?p=8873

Cheers, Glenn

-- 
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

- Raw text -