From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 83719 invoked by alias); 29 Jul 2019 15:40:54 -0000 Mailing-List: contact cygwin-help@cygwin.com; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cygwin-owner@cygwin.com Mail-Followup-To: cygwin@cygwin.com Received: (qmail 83712 invoked by uid 89); 29 Jul 2019 15:40:54 -0000 Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=-105.1 required=5.0 tests=AWL,BAYES_00,GOOD_FROM_CORINNA_CYGWIN,RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 spammy= X-HELO: mout.kundenserver.de Received: from mout.kundenserver.de (HELO mout.kundenserver.de) (212.227.126.131) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Mon, 29 Jul 2019 15:40:52 +0000 Received: from calimero.vinschen.de ([24.134.7.25]) by mrelayeu.kundenserver.de (mreue010 [212.227.15.167]) with ESMTPSA (Nemesis) id 1MMG6Y-1i891202sg-00JI7P for ; Mon, 29 Jul 2019 17:40:50 +0200 Received: by calimero.vinschen.de (Postfix, from userid 500) id 62BBCA80431; Mon, 29 Jul 2019 17:40:49 +0200 (CEST) Date: Mon, 29 Jul 2019 15:40:00 -0000 From: Corinna Vinschen To: cygwin@cygwin.com Subject: Re: Regression (last snapshot) Message-ID: <20190729154049.GR11632@calimero.vinschen.de> Reply-To: cygwin@cygwin.com Mail-Followup-To: cygwin@cygwin.com References: <20190722164509.GG21169@calimero.vinschen.de> <4b59209a91e8384ec000e2724696791c@smtp-cloud7.xs4all.net> <935d8ce5-fd5c-3010-4664-bb2dc9b7ca2f@cornell.edu> <20190729084552.GL11632@calimero.vinschen.de> <20190729134700.GO11632@calimero.vinschen.de> <20190729152327.GQ11632@calimero.vinschen.de> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="S0GG+JvAI2G0KxBG" Content-Disposition: inline In-Reply-To: <20190729152327.GQ11632@calimero.vinschen.de> User-Agent: Mutt/1.11.3 (2019-02-01) X-SW-Source: 2019-07/txt/msg00260.txt.bz2 --S0GG+JvAI2G0KxBG Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Content-length: 1388 On Jul 29 17:23, Corinna Vinschen wrote: > On Jul 29 14:26, Ken Brown wrote: > > On 7/29/2019 9:47 AM, Corinna Vinschen wrote: > > > On Jul 29 13:18, Ken Brown wrote: > > >> $ strace -o trace.out ls -lL <(grep bash .bashrc) > > >> ls: cannot access '/dev/fd/63': No such file or directory > > >=20 > > > No, please run bash: > > >=20 > > > strace -o trace.out bash -c 'ls -lL <(grep bash .bashrc)' > > >=20 > > > Otherwise there's no process actually creating the pipe, given the <() > > > expression is a bash expression. > >=20 > > Yes, of course. I should have realized this since it's exactly what I > > did under gdb. Anyway, the result is the same as it was under gdb: If > > I run the command under strace, I don't see the broken pipe error. > >=20 > > Is it possible that debugging causes an fd to the read end of the pipe > > to stay open longer, thereby preventing the error? >=20 > The fact that you observe it sporadically points to a race condition. > Debugging serializes stuff usually running in parallel, potentially > eliminating the race. Is there any chance this is a BLODA problem? If /dev/fd/63 doesn't exist in ls, it would mean ls didn't inherit the FIFO, which sounds very unlikely. I ran the ls call in a loop a couple of 1000 times, even in parallel windows including xterm and I just can't reproduce. Corinna --=20 Corinna Vinschen Cygwin Maintainer --S0GG+JvAI2G0KxBG Content-Type: application/pgp-signature; name="signature.asc" Content-length: 833 -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEEoVYPmneWZnwT6kwF9TYGna5ET6AFAl0/E4EACgkQ9TYGna5E T6CFlQ/+KC/8G7ao8FCeAYxs82jc/xqLeWTDd0suisszWvINjQAM5azbBqpkE+lw 7pwnIKDbFmgkY+b/u6KdanyIs2FFdyJR/lJO2CzN9dxN0NxoleGjpPV4iPt5QL1W xkttGU/3R4qeAU5+kQGm1OhDyIQ2NWdpp6+vPzMJWmvRyy/yvQQkchQ+JB4lHLd5 7rYH8dXuJet5Lb/5zDBcIVuWYkY+Bwq2I8UKSb8uUMEx3buO7MvtrU/e9vpeuo4t Yhl2FXWPX9t0LhnOYGBZ12xUxweUN3W926jCxQGl+2vJa6djvPhCgLAAtIzEjfVz vN2kcD3t9YXPMFZttxVMPbgCvC4m0j189dI41PzJyd3dE4g2mLZOVEE5DjQjBeJp HiiJFHUPj1/jtJ4bYAWia4bXrZNAytwIaFS3mKU0fPxTeESQfZFr6zYi+QesK/Xu Qpfd2UamD4L4pA7bjkQIIhhwStqaK3tbsF8Cxd6U0zTH/00TsQRPnQ3LYOmZBj3Y zL2pQAECUeC2hQF+DO0nxaSLOzIjSiWtlmeDRRPgKG96/8l9ZFwtrXoE7FddoM+R ax+y6xxXsDga+D92BFFx7Ab1gthtrBp+OzUVhlKQS5wppZiXUQo5X7T7LO6J05pu tXjBU/Su5a43HtzFo+RcYU3U1aa3cEgGwsrB2v2ubTF2N3gl24A= =487v -----END PGP SIGNATURE----- --S0GG+JvAI2G0KxBG--