From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 9021 invoked by alias); 28 May 2003 15:31:07 -0000 Mailing-List: contact gdb-help@sources.redhat.com; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-owner@sources.redhat.com Received: (qmail 9013 invoked from network); 28 May 2003 15:31:07 -0000 Received: from unknown (HELO aragorn.inter.net.il) (192.114.186.23) by sources.redhat.com with SMTP; 28 May 2003 15:31:07 -0000 Received: from zaretsky (tony08-232-64.inter.net.il [80.230.232.64] (may be forged)) by aragorn.inter.net.il (Mirapoint Messaging Server MOS 3.2.2-GA) with ESMTP id ASJ66099; Wed, 28 May 2003 18:30:06 +0300 (IDT) Date: Wed, 28 May 2003 15:31:00 -0000 From: "Eli Zaretskii" To: sick_soul@yahoo.it Message-Id: <8011-Wed28May2003183122+0300-eliz@elta.co.il> CC: gdb@sources.redhat.com In-reply-to: <20030528045321.87485.qmail@web40412.mail.yahoo.com> (message from =?iso-8859-1?q?Claudio=20Fontana?= on Wed, 28 May 2003 06:53:21 +0200 (CEST)) Subject: Re: [ feature request ] : software watchpoints, search byte pattern Reply-to: Eli Zaretskii References: <20030528045321.87485.qmail@web40412.mail.yahoo.com> X-SW-Source: 2003-05/txt/msg00365.txt.bz2 > Date: Wed, 28 May 2003 06:53:21 +0200 (CEST) > From: =?iso-8859-1?q?Claudio=20Fontana?= > > Hello, > do you think these features can be added in the > following versions? > > - software watchpoints: rwatch and awatch which, if > hardware breakpoints are not available, revert to > software ones To implement software watchpoints, GDB single-steps the program being debugged, and checks after each instruction whether the data being watched has changed its value. It is impossible to implement read watchpoints this way, since there's no way to know whether the last instruction accessed the data being watched: reading the data doesn't change its value. For that reason, rwatch and awatch are only available if hardware-assisted watchpoints are available.