From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 5413 invoked by alias); 14 Mar 2011 20:26:21 -0000 Received: (qmail 5402 invoked by uid 22791); 14 Mar 2011 20:26:20 -0000 X-SWARE-Spam-Status: No, hits=-2.4 required=5.0 tests=AWL,BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,RCVD_IN_DNSWL_LOW,TW_GT,T_RP_MATCHES_RCVD X-Spam-Check-By: sourceware.org Received: from sif.is.scarlet.be (HELO sif.is.scarlet.be) (193.74.71.28) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Mon, 14 Mar 2011 20:26:17 +0000 Received: from [172.17.1.10] (ip-81-11-247-249.dsl.scarlet.be [81.11.247.249]) by sif.is.scarlet.be (8.14.2/8.14.2) with ESMTP id p2EKQDWP027760; Mon, 14 Mar 2011 21:26:14 +0100 Subject: gdb influencing app behaviour ? From: Danny Backx Reply-To: danny.backx@scarlet.be To: gdb Content-Type: text/plain; charset="UTF-8" Date: Mon, 14 Mar 2011 20:26:00 -0000 Message-ID: <1300134373.2002.8.camel@pavilion> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit X-DCC-scarlet.be-Metrics: sif 20001; Body=2 Fuz1=2 Fuz2=2 X-IsSubscribed: yes Mailing-List: contact gdb-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-owner@sourceware.org X-SW-Source: 2011-03/txt/msg00099.txt.bz2 Hi, I was trying to debug the interaction between RoadMap and gpsd's client library recently. I believe I've found my problem, but I think gdb influenced application behaviour in a way I'd like to understand. The application uses some gtk call which presumably ends up using select(2) to trigger a function when data can be read from a socket. The application appears to behave differently when I set a breakpoint in that function. (The application and the library were both trying to read from the socket, by setting the breakpoint the other one would always win the race.) How can this be explained ? Am I wrong ? This is on Ubuntu on a regular PC. http://sf.net/projects/roadmap and http://gpsd.berlios.de . Danny -- Danny Backx ; danny.backx - at - scarlet.be ; http://danny.backx.info