From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 78816 invoked by alias); 30 May 2016 20:02:58 -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 78808 invoked by uid 89); 30 May 2016 20:02:57 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.7 required=5.0 tests=AWL,BAYES_00,RP_MATCHES_RCVD,SPF_HELO_PASS,SPF_PASS autolearn=ham version=3.3.2 spammy=Was, exhibits, D*cx, oct X-HELO: limerock02.mail.cornell.edu Received: from limerock02.mail.cornell.edu (HELO limerock02.mail.cornell.edu) (128.84.13.242) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Mon, 30 May 2016 20:02:47 +0000 X-CornellRouted: This message has been Routed already. Received: from authusersmtp.mail.cornell.edu (granite4.serverfarm.cornell.edu [10.16.197.9]) by limerock02.mail.cornell.edu (8.14.4/8.14.4_cu) with ESMTP id u4UK2jH3026243 for ; Mon, 30 May 2016 16:02:45 -0400 Received: from [192.168.1.5] (mta-68-175-148-36.twcny.rr.com [68.175.148.36] (may be forged)) (authenticated bits=0) by authusersmtp.mail.cornell.edu (8.14.4/8.12.10) with ESMTP id u4UK2ikV013914 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES128-SHA bits=128 verify=NOT) for ; Mon, 30 May 2016 16:02:45 -0400 Subject: gdb pty problem [Was: emacs gud-interface is not updated after gdb command execution (maybe because of incomplete output from gdb)] To: cygwin@cygwin.com References: <466943424.37628.394d161a-7219-415d-a659-0f774811ad2d.open-xchange@email.1und1.de> <44459aa0-4381-2368-ab63-5dffc26f3344@cornell.edu> From: Ken Brown Message-ID: Date: Tue, 31 May 2016 01:47:00 -0000 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.1.0 MIME-Version: 1.0 In-Reply-To: <44459aa0-4381-2368-ab63-5dffc26f3344@cornell.edu> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit X-PMX-Cornell-Gauge: Gauge=XXXXX X-IsSubscribed: yes X-SW-Source: 2016-05/txt/msg00413.txt.bz2 On 5/26/2016 8:31 AM, Ken Brown wrote: > This looks like a bug I reported several years ago; it actually has > nothing to do with emacs: > > https://www.cygwin.com/ml/cygwin/2011-10/msg00445.html > > It was fixed but then reappeared some months later: > > https://www.cygwin.com/ml/cygwin/2012-05/msg00049.html > > It was fixed again but apparently is back. The test case from the > original report still exhibits the problem. I've tracked down the commits that fixed this bug in the past. The first fix was commit 31d2bedc585420092eb53895c5f5646651f13215 Author: Christopher Faylor Date: Sun Oct 23 19:01:47 2011 +0000 * fhandler_tty.cc (fhandler_pty_slave::read): Use consistent way for testing ReadFile return. * pipe.cc (fhandler_pipe::create_selectable): Open the write side of the pipe in message-mode to force writing as "chunks". Explain why. The second was commit fb9d631817cc2b5d83c2a6ff928851d201c992bf Author: Christopher Faylor Date: Fri May 4 03:00:43 2012 +0000 * DevNotes: Add entry cgf-000002. * fhandler_tty.cc (bytes_available): Revert to previous Oct-2011 behavior where a dummy buffer is used to determine how many bytes will be read. (fhandler_pty_master::ioctl): Correct coercion in assignment. A few weeks later the code was simplified: commit bd8afa5eb160b56715b805befe850a5ba2131d28 Author: Christopher Faylor Date: Wed May 16 01:56:41 2012 +0000 * DevNotes: Add entry cgf-000008. * fhandler_tty.cc (bytes_available): Simplify by returning the number of bytes available in the message unless that is zero. I've looked at the current code in the vicinity of these changes, and nothing jumps out at me as obviously breaking the previous fixes; but that doesn't mean much. Ken -- 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