From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gdb-return-38864-listarch-gdb=sources.redhat.com@sourceware.org>
Received: (qmail 14458 invoked by alias); 22 Mar 2011 16:40:55 -0000
Received: (qmail 14414 invoked by uid 22791); 22 Mar 2011 16:40:54 -0000
X-SWARE-Spam-Status: No, hits=-6.9 required=5.0	tests=AWL,BAYES_00,RCVD_IN_DNSWL_HI,SPF_HELO_PASS,T_RP_MATCHES_RCVD
X-Spam-Check-By: sourceware.org
Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28)    by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Tue, 22 Mar 2011 16:40:45 +0000
Received: from int-mx02.intmail.prod.int.phx2.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12])	by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id p2MGehBm003399	(version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK);	Tue, 22 Mar 2011 12:40:43 -0400
Received: from ns3.rdu.redhat.com (ns3.rdu.redhat.com [10.11.255.199])	by int-mx02.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id p2MGegB0010712;	Tue, 22 Mar 2011 12:40:42 -0400
Received: from opsy.redhat.com (ovpn01.gateway.prod.ext.phx2.redhat.com [10.5.9.1])	by ns3.rdu.redhat.com (8.13.8/8.13.8) with ESMTP id p2MGefG2012447;	Tue, 22 Mar 2011 12:40:42 -0400
Received: by opsy.redhat.com (Postfix, from userid 500)	id 2488A378491; Tue, 22 Mar 2011 10:40:41 -0600 (MDT)
From: Tom Tromey <tromey@redhat.com>
To: Keith Goldberg <keith.goldberg@actifio.com>
Cc: gdb@sourceware.org
Subject: Re: Walking an array of structs under gdb-Python
References: <AANLkTikzMH8QgAZRUEt-VNjaT4+3a_Go9BeUNSkpUL+=@mail.gmail.com>
Date: Tue, 22 Mar 2011 16:40:00 -0000
In-Reply-To: <AANLkTikzMH8QgAZRUEt-VNjaT4+3a_Go9BeUNSkpUL+=@mail.gmail.com>	(Keith Goldberg's message of "Fri, 18 Mar 2011 13:02:04 -0400")
Message-ID: <m3pqpjrtva.fsf@fleche.redhat.com>
User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.2 (gnu/linux)
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Mailing-List: contact gdb-help@sourceware.org; run by ezmlm
Precedence: bulk
List-Id: <gdb.sourceware.org>
List-Subscribe: <mailto:gdb-subscribe@sourceware.org>
List-Archive: <http://sourceware.org/ml/gdb/>
List-Post: <mailto:gdb@sourceware.org>
List-Help: <mailto:gdb-help@sourceware.org>, <http://sourceware.org/ml/#faqs>
Sender: gdb-owner@sourceware.org
X-SW-Source: 2011-03/txt/msg00118.txt.bz2

Keith> Can someone please point me to an example of how to walk through an
Keith> array of structs using python under GDB? Presuming I have malloc'd
Keith> enough space for 100 of mystruct, I would like to be able to use
Keith> "pointer math" to inspect each element and its members at will. I
Keith> appreciate any pointer to the right resource.

I don't know of an example offhand, but it should pretty much work as
you'd expect.

Suppose you have 'type *array' in the source.

python v = gdb.parse_and_eval('array')
python print v.dereference()        # print array[0]
python print (v + 1).dereference()  # print array[1]
python print (v + 2)['field']       # print array[2].field

Tom