X-Recipient: archive-cygwin AT delorie DOT com X-Spam-Check-By: sourceware.org Date: Tue, 9 Feb 2010 11:34:46 -0500 From: Christopher Faylor To: cygwin AT cygwin DOT com Subject: Re: poll() on fifo read descriptor with non-zero timeout ==> segfault Message-ID: <20100209163446.GA18306@ednor.casa.cgf.cx> Reply-To: cygwin AT cygwin DOT com Mail-Followup-To: cygwin AT cygwin DOT com References: <4B6E470D DOT 9080607 AT monai DOT ca> <20100209085426 DOT GW28659 AT calimero DOT vinschen DOT de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20100209085426.GW28659@calimero.vinschen.de> User-Agent: Mutt/1.5.20 (2009-06-14) Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , 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 Tue, Feb 09, 2010 at 09:54:26AM +0100, Corinna Vinschen wrote: >On Feb 6 20:52, Steven Monai wrote: >> Hi folks, >> >> Here is a short test case I've named "fifo-read.c": >> [...] >> Here's what happens at the command line: >> >> $ uname -a >> CYGWIN_NT-5.1 lonestar 1.7.1(0.218/5/3) 2009-12-07 11:48 i686 Cygwin >> >> $ gcc-4 -Wall -Werror -ansi -pedantic -o fifo-read fifo-read.c >> >> $ mkfifo -m0600 myfifo >> >> $ ls -l >> total 29 >> -rw-r--r--+ 1 steve None 939 2010-02-06 20:25 fifo-read.c >> -rwxr-xr-x+ 1 steve None 22792 2010-02-06 20:25 fifo-read.exe >> prw------- 1 steve None 0 2010-02-06 20:25 myfifo >> >> $ ./fifo-read >> About to enter poll() >> Segmentation fault (core dumped) >> >> >> If I change the timeout to a positive number, it also segfaults. >> >> If I change the timeout to zero, it works, but poll() returns >> immediately with no descriptor ready to read. Not very useful. >> >> I get identical results on two different machines, with two different >> OSes (XP and 2000). Can anyone else reproduce this? Am I using poll() >> incorrectly? > >Can you check with the latest snapshot from http://cygwin.com/snapshots, >please? I can not reproduce the above crash with your test application >when using Cygwin from CVS, neither on XP, nor on Windows 7. Relevant threads: http://cygwin.com/ml/cygwin/2009-12/threads.html#00685 http://cygwin.com/ml/cygwin/2010-01/msg00067.html Bottom line: The crash is fixed but cygwin still doesn't work right. 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