X-Recipient:	archive-cygwin AT delorie DOT com
X-Spam-Check-By:	sourceware.org
Date:	Tue, 15 Dec 2009 18:10:51 +0100
From:	Corinna Vinschen <corinna-cygwin AT cygwin DOT com>
To:	cygwin AT cygwin DOT com
Subject:	Re: SO_REUSEADDR and windows enhanced socket security
Message-ID:	<20091215171051.GH8059@calimero.vinschen.de>
Reply-To:	cygwin AT cygwin DOT com
Mail-Followup-To:	cygwin AT cygwin DOT com
References:	<4B27AFEB DOT 4030609 AT gmail DOT com>
MIME-Version:	1.0
In-Reply-To:	<4B27AFEB.4030609@gmail.com>
User-Agent:	Mutt/1.5.20 (2009-06-14)
Mailing-List:	contact cygwin-help AT cygwin DOT com; run by ezmlm
List-Id:	<cygwin.cygwin.com>
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

On Dec 15 18:48, yesin wrote:
> looks like a problem with SO_REUSEADDR exists in CYGWIN for all
> windows with support for "Enhanced socket security" (see
> http://msdn.microsoft.com/en-us/library/ms740621(VS.85).aspx <http://www.google.com/url?sa=D&q=http://msdn.microsoft.com/en-us/library/ms740621%28VS.85%29.aspx&usg=AFQjCNF9bXOmPTwYjiP37Xdq2xRAYNXfWg>)
> 
> 
> i'am trying to start multimple simultaneous UDP listeners for a
> multicast packets on a single machine (reuse same address and port
> with SO_REUSEADDR)
> [...]
> with cygwin environment i can't run multiple listerers... bind error:
> Address already in use!

Thanks for the report and especially thanks for the testcase.  There
is code in Cygwin which skips calls to setsockopt(SO_REUSEADDR) on
systems supporting enhanced socket security.  That's necessary to
emulate socket re-binding behaviour more closely to POSIX behaviour.
The problem was that this should have been only called for TCP sockets
but Cygwin accidentally called it for UDP sockets as well.  I fixed
that in CVS.


Thanks again,
Corinna

-- 
Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Project Co-Leader          cygwin AT cygwin DOT com
Red Hat

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

- Raw text -