X-Recipient: archive-cygwin@delorie.com X-SWARE-Spam-Status: No, hits=-1.8 required=5.0 tests=AWL,BAYES_00,RCVD_IN_DNSWL_NONE X-Spam-Check-By: sourceware.org X-Mail-Handler: MailHop Outbound by DynDNS X-Report-Abuse-To: abuse@dyndns.com (see http://www.dyndns.com/services/mailhop/outbound_abuse.html for abuse reporting information) X-MHO-User: U2FsdGVkX184W80n9DpxSinhmzSjWUcD Date: Mon, 12 Mar 2012 18:02:04 -0400 From: Christopher Faylor To: cygwin@cygwin.com Subject: Re: Can't reliably redirect standard output from C# program in recent Cygwin Message-ID: <20120312220204.GA29921@ednor.casa.cgf.cx> Reply-To: cygwin@cygwin.com Mail-Followup-To: cygwin@cygwin.com References: <004e01ccfd70$c69af3f0$53d0dbd0$@motionview3d.com> <005c01ccfd79$6341f980$29c5ec80$@motionview3d.com> <007201ccfe25$130065e0$390131a0$@motionview3d.com> <20120309195247.GB18960@calimero.vinschen.de> <20120311013339.GA32518@ednor.casa.cgf.cx> <00b701cd0059$25c26a80$71473f80$@motionview3d.com> <20120312141929.GE2382@calimero.vinschen.de> <00cf01cd0075$8430b290$8c9217b0$@motionview3d.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <00cf01cd0075$8430b290$8c9217b0$@motionview3d.com> User-Agent: Mutt/1.5.20 (2009-06-14) Mailing-List: contact cygwin-help@cygwin.com; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cygwin-owner@cygwin.com Mail-Followup-To: cygwin@cygwin.com Delivered-To: mailing list cygwin@cygwin.com On Mon, Mar 12, 2012 at 05:28:17PM -0000, James Johnston wrote: >Well, good call. I shouldn't have jumped to conclusions. Both my C++ >and C# examples still fail: Not really a call. It was obviously different failure. The previous fix wasn't even pipe related. But, regardless, Corinna (who has more time these days to look into this type of thing) found a damning piece of MSDN documentation which indicates that a write of zero bytes to a pipe will cause a read of zero bytes on the other end of the pipe. So, a program which assumes that a zero byte read means EOF, like most Linux programs, will stop processing when it sees the zero bytes from ReadFile. Corinna sent me a patch to fix the problem which I've mildly tweaked and installed. It's in the latest snapshot. cgf -- 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