From: Eric Sandeen Subject: Re: sparsify - utility to punch out blocks of 0s in a file Date: Sun, 05 Feb 2012 11:21:26 -0600 Message-ID: <4F2EBA96.2070603@redhat.com> References: <4F2D8F30.3090802@redhat.com> <201202050933.q159XQpB026380@helium.internal.tigress.co.uk> <4F2EB017.5090006@redhat.com> <201202051719.q15HJJme010040@helium.internal.tigress.co.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: xfs@oss.sgi.com, linux-ext4@vger.kernel.org To: Ron Yorston Return-path: Received: from mx1.redhat.com ([209.132.183.28]:35957 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753888Ab2BERVb (ORCPT ); Sun, 5 Feb 2012 12:21:31 -0500 In-Reply-To: <201202051719.q15HJJme010040@helium.internal.tigress.co.uk> Sender: linux-ext4-owner@vger.kernel.org List-ID: On 2/5/12 11:19 AM, Ron Yorston wrote: > OK, I tried it out for my use case of flinging VM filesystem images around > on ext4 and it seems to do the job. I don't have any 64-bit systems > here at home so I used my feeble 32-bit netbook. Since sizeof(off_t) != > sizeof(long long) the debug output was all wrong: > > punching at 8989607068975104 len -4635819229210214401 whoops, I'll fix that thanks. This is the problem when I start something as a hack and then expose it to the light of day. ;) -Eric > but the image file and the host filesystem both survived the ordeal. > > Ron