From unknown Mon Aug 18 11:33:03 2025 X-Loop: help-debbugs@gnu.org Subject: bug#15680: dd: suggest iflag=fullblock ... but only if count > 1 Resent-From: Bernhard Voelker Original-Sender: "Debbugs-submit" Resent-CC: bug-coreutils@gnu.org Resent-Date: Tue, 22 Oct 2013 06:49:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: report 15680 X-GNU-PR-Package: coreutils X-GNU-PR-Keywords: To: 15680@debbugs.gnu.org X-Debbugs-Original-To: bug-coreutils@gnu.org Received: via spool by submit@debbugs.gnu.org id=B.13824245072174 (code B ref -1); Tue, 22 Oct 2013 06:49:02 +0000 Received: (at submit) by debbugs.gnu.org; 22 Oct 2013 06:48:27 +0000 Received: from localhost ([127.0.0.1]:34146 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1VYVlS-0000Yz-Pb for submit@debbugs.gnu.org; Tue, 22 Oct 2013 02:48:27 -0400 Received: from eggs.gnu.org ([208.118.235.92]:45704) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1VYVlP-0000Yl-Kj for submit@debbugs.gnu.org; Tue, 22 Oct 2013 02:48:24 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1VYVlA-0007Y4-Sq for submit@debbugs.gnu.org; Tue, 22 Oct 2013 02:48:18 -0400 X-Spam-Checker-Version: SpamAssassin 3.3.2 (2011-06-06) on eggs.gnu.org X-Spam-Level: X-Spam-Status: No, score=0.8 required=5.0 tests=BAYES_50 autolearn=disabled version=3.3.2 Received: from lists.gnu.org ([2001:4830:134:3::11]:58063) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VYVlA-0007Xz-PQ for submit@debbugs.gnu.org; Tue, 22 Oct 2013 02:48:08 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:47396) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VYVl3-00051r-EI for bug-coreutils@gnu.org; Tue, 22 Oct 2013 02:48:08 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1VYVkw-0007VX-4P for bug-coreutils@gnu.org; Tue, 22 Oct 2013 02:48:01 -0400 Received: from moutng.kundenserver.de ([212.227.17.9]:62577) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VYVkv-0007VN-Qu for bug-coreutils@gnu.org; Tue, 22 Oct 2013 02:47:54 -0400 Received: from [192.168.1.11] (p5499C931.dip0.t-ipconnect.de [84.153.201.49]) by mrelayeu.kundenserver.de (node=mrbap0) with ESMTP (Nemesis) id 0MS0Vu-1V9r6j1Jk2-00TRYZ; Tue, 22 Oct 2013 08:47:51 +0200 Message-ID: <52661F96.9080402@bernhard-voelker.de> Date: Tue, 22 Oct 2013 08:47:50 +0200 From: Bernhard Voelker User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130329 Thunderbird/17.0.5 MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Provags-ID: V02:K0:q5Iy05EGG57082bXgmwwceSEj8yPxgUEzP9uvw/ruWX tmRDBDmV2x1HSm35tfjFn+X+caTQ8OoFoURNfl66l1/lgRZpw1 7p10TQIsLOBIZ9DCE9S/qApg85uGut7BizTlRJuDhfEupmrlPn u0HBBMmZ9f4s9tMVsvNK2htmkOYet7WgmebIfCvEY18x2aXBse 878e0LVku8YWPP9vOXpUrj6gUn/BEqAW5d/sH3iIW4VQscoKNN 8EWrzcz8riz/dDxeH8vW+QGK9Oj01J1nlTeYM7p5q/d3B7Jlui ITsICdoM6QyvwHZSRCNe8ojzDXqpTAFCH6L6H0VszUVTzfs5Vw OQsajCVCEaXYZ24xPzpnE6rUiqSiyKv+pxvHFePQe X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.4.x-2.6.x [generic] X-detected-operating-system: by eggs.gnu.org: Error: Malformed IPv6 address (bad octet value). X-Received-From: 2001:4830:134:3::11 X-Spam-Score: -5.0 (-----) X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: debbugs-submit-bounces@debbugs.gnu.org Sender: "Debbugs-submit" X-Spam-Score: -5.0 (-----) dd(1) issues a nice warning about short reads ... src/dd if=/dev/random of=sample bs=1000 count=2 src/dd: warning: partial read (128 bytes); suggest iflag=fullblock 0+2 records in 0+2 records out 256 bytes (256 B) copied, 0.000423371 s, 605 kB/s ... but only if count was > 1: src/dd if=/dev/random of=sample bs=1000 count=1 0+1 records in 0+1 records out 128 bytes (128 B) copied, 0.000270231 s, 474 kB/s Is this by intension or an off-by-one? I'd like to provide a patch in the latter case. Have a nice day, Berny From unknown Mon Aug 18 11:33:03 2025 X-Loop: help-debbugs@gnu.org Subject: bug#15680: dd: suggest iflag=fullblock ... but only if count > 1 Resent-From: Eric Blake Original-Sender: "Debbugs-submit" Resent-CC: bug-coreutils@gnu.org Resent-Date: Tue, 22 Oct 2013 07:06:01 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 15680 X-GNU-PR-Package: coreutils X-GNU-PR-Keywords: To: Bernhard Voelker , 15680@debbugs.gnu.org Received: via spool by 15680-submit@debbugs.gnu.org id=B15680.13824255263775 (code B ref 15680); Tue, 22 Oct 2013 07:06:01 +0000 Received: (at 15680) by debbugs.gnu.org; 22 Oct 2013 07:05:26 +0000 Received: from localhost ([127.0.0.1]:34169 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1VYW1t-0000yo-SL for submit@debbugs.gnu.org; Tue, 22 Oct 2013 03:05:26 -0400 Received: from mx1.redhat.com ([209.132.183.28]:48376) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1VYW1p-0000ye-SS for 15680@debbugs.gnu.org; Tue, 22 Oct 2013 03:05:23 -0400 Received: from int-mx01.intmail.prod.int.phx2.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id r9M75Gnk015200 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Tue, 22 Oct 2013 03:05:16 -0400 Received: from [10.3.113.153] (ovpn-113-153.phx2.redhat.com [10.3.113.153]) by int-mx01.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id r9M75DMP019186; Tue, 22 Oct 2013 03:05:14 -0400 Message-ID: <526623A8.9050103@redhat.com> Date: Tue, 22 Oct 2013 08:05:12 +0100 From: Eric Blake Organization: Red Hat, Inc. User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.0 MIME-Version: 1.0 References: <52661F96.9080402@bernhard-voelker.de> In-Reply-To: <52661F96.9080402@bernhard-voelker.de> X-Enigmail-Version: 1.6 OpenPGP: url=http://people.redhat.com/eblake/eblake.gpg Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="GP8Lqc9WaqQcIgHmXcQr5Wetb815bLwo4" X-Scanned-By: MIMEDefang 2.67 on 10.5.11.11 X-Spam-Score: -5.4 (-----) X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: debbugs-submit-bounces@debbugs.gnu.org Sender: "Debbugs-submit" X-Spam-Score: -5.4 (-----) This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --GP8Lqc9WaqQcIgHmXcQr5Wetb815bLwo4 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On 10/22/2013 07:47 AM, Bernhard Voelker wrote: > dd(1) issues a nice warning about short reads ... >=20 > src/dd if=3D/dev/random of=3Dsample bs=3D1000 count=3D2 > src/dd: warning: partial read (128 bytes); suggest iflag=3Dfullblock > 0+2 records in > 0+2 records out > 256 bytes (256 B) copied, 0.000423371 s, 605 kB/s >=20 > ... but only if count was > 1: >=20 > src/dd if=3D/dev/random of=3Dsample bs=3D1000 count=3D1 > 0+1 records in > 0+1 records out > 128 bytes (128 B) copied, 0.000270231 s, 474 kB/s >=20 > Is this by intension or an off-by-one? My understanding is that it is intentional. --=20 Eric Blake eblake redhat com +1-919-301-3266 Libvirt virtualization library http://libvirt.org --GP8Lqc9WaqQcIgHmXcQr5Wetb815bLwo4 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.15 (GNU/Linux) Comment: Public key at http://people.redhat.com/eblake/eblake.gpg Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iQEcBAEBCAAGBQJSZiOoAAoJEKeha0olJ0NqOyEH/AtjM7V1wWSECDRfHqvlyGLk IJuctVjBel8uyfTSnTfXlVtzDyQqeoSGJTOauMEZezM6GLcPJAflsSIGuvAE2uIC zO5IPiDx+UWSvqJjPaf/YloTbwMJhvl52LFN2ryV8oXXpIxBENKImUhEMAjM1t5C yxrXAw5CbCFnhhxZ9UwpKCEmZNUy1iPHv7ZCqMrt+vpPdYWkcQgNpvqG3RJ36llY iLjzCeqxD47CcvywKaIWFAbf/Ai+LrqKillMBItq1kZa+xnWU3RLw2ybl4YACGTt BOMkVCtBtx57lHs8l3xcLZJNN3aRNwJtXGxa8vXfm/epG0oAd4v78HNqQMUzUck= =KVG/ -----END PGP SIGNATURE----- --GP8Lqc9WaqQcIgHmXcQr5Wetb815bLwo4-- From unknown Mon Aug 18 11:33:03 2025 X-Loop: help-debbugs@gnu.org Subject: bug#15680: dd: suggest iflag=fullblock ... but only if count > 1 Resent-From: =?UTF-8?Q?P=C3=A1draig?= Brady Original-Sender: "Debbugs-submit" Resent-CC: bug-coreutils@gnu.org Resent-Date: Tue, 22 Oct 2013 09:27:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 15680 X-GNU-PR-Package: coreutils X-GNU-PR-Keywords: To: Bernhard Voelker Cc: 15680@debbugs.gnu.org Received: via spool by 15680-submit@debbugs.gnu.org id=B15680.138243396621252 (code B ref 15680); Tue, 22 Oct 2013 09:27:02 +0000 Received: (at 15680) by debbugs.gnu.org; 22 Oct 2013 09:26:06 +0000 Received: from localhost ([127.0.0.1]:34316 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1VYYE1-0005Wg-8n for submit@debbugs.gnu.org; Tue, 22 Oct 2013 05:26:05 -0400 Received: from mail4.vodafone.ie ([213.233.128.170]:8223) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1VYYDs-0005W3-ML; Tue, 22 Oct 2013 05:25:57 -0400 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: ApwBALxDZlJtTvAx/2dsb2JhbAANTIM/Tr5HgTyDGQEBAQQyAUYQCw0BCgkWDwkDAgECAUUGDQEHAQGIBwOnLpNKj0YHhCkDmTiFM4VxiFk Received: from unknown (HELO [192.168.1.79]) ([109.78.240.49]) by mail3.vodafone.ie with ESMTP; 22 Oct 2013 10:25:49 +0100 Message-ID: <5266449D.8030905@draigBrady.com> Date: Tue, 22 Oct 2013 10:25:49 +0100 From: =?UTF-8?Q?P=C3=A1draig?= Brady User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130110 Thunderbird/17.0.2 MIME-Version: 1.0 References: <52661F96.9080402@bernhard-voelker.de> In-Reply-To: <52661F96.9080402@bernhard-voelker.de> X-Enigmail-Version: 1.5.2 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit X-Spam-Score: 0.0 (/) X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: debbugs-submit-bounces@debbugs.gnu.org Sender: "Debbugs-submit" X-Spam-Score: 0.0 (/) tag 15680 notabug close 15680 stop On 10/22/2013 07:47 AM, Bernhard Voelker wrote: > dd(1) issues a nice warning about short reads ... > > src/dd if=/dev/random of=sample bs=1000 count=2 > src/dd: warning: partial read (128 bytes); suggest iflag=fullblock > 0+2 records in > 0+2 records out > 256 bytes (256 B) copied, 0.000423371 s, 605 kB/s > > ... but only if count was > 1: > > src/dd if=/dev/random of=sample bs=1000 count=1 > 0+1 records in > 0+1 records out > 128 bytes (128 B) copied, 0.000270231 s, 474 kB/s > > Is this by intension or an off-by-one? > I'd like to provide a patch in the latter case. The various cases for warning were disucussed at: http://bugs.gnu.org/7362 Also I mentioned this particular case with count at: http://bugs.gnu.org/9734#18 Copying from there... "Note the particular case where count=1 is not warned about, as with a single read, one doesn't know if we're just at EOF. Also it's probably a quite common idiom to, consume available data up to $bs bytes." thanks, P�draig. From unknown Mon Aug 18 11:33:03 2025 X-Loop: help-debbugs@gnu.org Subject: bug#15680: dd: suggest iflag=fullblock ... but only if count > 1 Resent-From: Bernhard Voelker Original-Sender: "Debbugs-submit" Resent-CC: bug-coreutils@gnu.org Resent-Date: Tue, 22 Oct 2013 10:27:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 15680 X-GNU-PR-Package: coreutils X-GNU-PR-Keywords: notabug To: =?UTF-8?Q?P=C3=A1draig?= Brady Cc: 15680@debbugs.gnu.org Reply-To: Bernhard Voelker Received: via spool by 15680-submit@debbugs.gnu.org id=B15680.138243759931249 (code B ref 15680); Tue, 22 Oct 2013 10:27:02 +0000 Received: (at 15680) by debbugs.gnu.org; 22 Oct 2013 10:26:39 +0000 Received: from localhost ([127.0.0.1]:34425 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1VYZAc-00087x-Lf for submit@debbugs.gnu.org; Tue, 22 Oct 2013 06:26:39 -0400 Received: from moutng.kundenserver.de ([212.227.126.186]:59876) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1VYZAZ-00087f-0o for 15680@debbugs.gnu.org; Tue, 22 Oct 2013 06:26:36 -0400 Received: from oxbaltgw10.schlund.de (oxbaltgw10.schlund.de [172.19.246.16]) by mrelayeu.kundenserver.de (node=mreu3) with ESMTP (Nemesis) id 0M0GPh-1Vrccb1coX-00ubIQ; Tue, 22 Oct 2013 12:26:28 +0200 Date: Tue, 22 Oct 2013 12:26:28 +0200 (CEST) From: Bernhard Voelker Message-ID: <1221012425.432486.1382437588425.open-xchange@email.1und1.de> In-Reply-To: <5266449D.8030905@draigBrady.com> References: <52661F96.9080402@bernhard-voelker.de> <5266449D.8030905@draigBrady.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Priority: 3 Importance: Medium X-Mailer: Open-Xchange Mailer v7.2.2-Rev20 X-Provags-ID: V02:K0:IOQDl/kd5w5Tb5GrjXbvuU4S5v7WRTgGq/6JZFMrikJ /6/xte+j7KU0NJwZbnAJcHG+q8iGE0m0p5HoXYwZHM5gy/AlaN n2iTT6X8xi9e4bRNlGrIGDn2jLChQ+7/g0pverupvPTLtwThLk z69yiYZ1pduQpd0OC6qvi8oCcIVLY6uGwrtgXxxddmvj8RDxuL GiC6wmJK+GoumUkcmbfuN98hr7Xcf4sJhVRjgjHiTY13zW35nM DfszzAnsUheKanMM50ZRCYcoh1CCuCT0Hgjplg6uL9CjwKmszV yauSiMEq8YVhSOwK9MieJMDBqJ5K3fvpFt6Kor/ATt+5l4BV6e YRJ4WiMpT6fLXKYEz6E+Wwe8Ss1DFKOjErHnsScoL/bl37i3NI 1RFSqr4hd9ni3bofG50uah6xKw8GALJwts= X-Spam-Score: -0.0 (/) X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: debbugs-submit-bounces@debbugs.gnu.org Sender: "Debbugs-submit" X-Spam-Score: -0.0 (/) >=C2=A0On=C2=A0October=C2=A022,=C2=A02013=C2=A0at=C2=A011:25=C2=A0AM=C2=A0P= =C3=A1draig=C2=A0Brady=C2=A0=C2=A0wrote: >=C2=A0Also=C2=A0I=C2=A0mentioned=C2=A0this=C2=A0particular=C2=A0case=C2=A0= with=C2=A0count=C2=A0at: >=C2=A0http://bugs.gnu.org/9734#18 >=C2=A0 >=C2=A0Copying=C2=A0from=C2=A0there... >=C2=A0 >=C2=A0"Note=C2=A0the=C2=A0particular=C2=A0case=C2=A0where=C2=A0count=3D1= =C2=A0is=C2=A0not=C2=A0warned=C2=A0about, >=C2=A0as=C2=A0with=C2=A0a=C2=A0single=C2=A0read,=C2=A0one=C2=A0doesn't=C2= =A0know=C2=A0if=C2=A0we're=C2=A0just=C2=A0at=C2=A0EOF. >=C2=A0Also=C2=A0it's=C2=A0probably=C2=A0a=C2=A0quite=C2=A0common=C2=A0idio= m=C2=A0to,=C2=A0consume=C2=A0available=C2=A0data >=C2=A0up=C2=A0to=C2=A0$bs=C2=A0bytes." Thanks. To avoid that this question comes up again: should we add this into the Texinfo file? Have a nice day, Berny From unknown Mon Aug 18 11:33:03 2025 X-Loop: help-debbugs@gnu.org Subject: bug#15680: dd: suggest iflag=fullblock ... but only if count > 1 Resent-From: =?UTF-8?Q?P=C3=A1draig?= Brady Original-Sender: "Debbugs-submit" Resent-CC: bug-coreutils@gnu.org Resent-Date: Tue, 22 Oct 2013 11:04:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 15680 X-GNU-PR-Package: coreutils X-GNU-PR-Keywords: notabug To: Bernhard Voelker Cc: 15680@debbugs.gnu.org Received: via spool by 15680-submit@debbugs.gnu.org id=B15680.13824398212404 (code B ref 15680); Tue, 22 Oct 2013 11:04:02 +0000 Received: (at 15680) by debbugs.gnu.org; 22 Oct 2013 11:03:41 +0000 Received: from localhost ([127.0.0.1]:34473 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1VYZkS-0000ci-Ln for submit@debbugs.gnu.org; Tue, 22 Oct 2013 07:03:40 -0400 Received: from mail5.vodafone.ie ([213.233.128.176]:13065) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1VYZkO-0000cS-Qv for 15680@debbugs.gnu.org; Tue, 22 Oct 2013 07:03:37 -0400 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: ApwBAPtaZlJtTvAx/2dsb2JhbAANTIM/ToMwux6BPIMZAQEBBCMPAUYQCw0BCgICBRYLAgIJAwIBAgFFBg0BBQIBAYgHA6ctdZJTgSmOHQeCaoE/A5k4hTOOSg Received: from unknown (HELO [192.168.1.79]) ([109.78.240.49]) by mail3.vodafone.ie with ESMTP; 22 Oct 2013 12:03:11 +0100 Message-ID: <52665B6E.6020608@draigBrady.com> Date: Tue, 22 Oct 2013 12:03:10 +0100 From: =?UTF-8?Q?P=C3=A1draig?= Brady User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130110 Thunderbird/17.0.2 MIME-Version: 1.0 References: <52661F96.9080402@bernhard-voelker.de> <5266449D.8030905@draigBrady.com> <1221012425.432486.1382437588425.open-xchange@email.1und1.de> In-Reply-To: <1221012425.432486.1382437588425.open-xchange@email.1und1.de> X-Enigmail-Version: 1.5.2 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Spam-Score: 0.0 (/) X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: debbugs-submit-bounces@debbugs.gnu.org Sender: "Debbugs-submit" X-Spam-Score: 0.0 (/) On 10/22/2013 11:26 AM, Bernhard Voelker wrote: >> On October 22, 2013 at 11:25 AM Pádraig Brady wrote: >> Also I mentioned this particular case with count at: >> http://bugs.gnu.org/9734#18 >> >> Copying from there... >> >> "Note the particular case where count=1 is not warned about, >> as with a single read, one doesn't know if we're just at EOF. >> Also it's probably a quite common idiom to, consume available data >> up to $bs bytes." > > Thanks. > To avoid that this question comes up again: should we add > this into the Texinfo file? Maybe, though we have to be careful of coupling the docs too tightly with the code. Worth a source comment at least. From unknown Mon Aug 18 11:33:03 2025 X-Loop: help-debbugs@gnu.org Subject: bug#15680: dd: suggest iflag=fullblock ... but only if count > 1 Resent-From: Bernhard Voelker Original-Sender: "Debbugs-submit" Resent-CC: bug-coreutils@gnu.org Resent-Date: Tue, 22 Oct 2013 13:15:03 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 15680 X-GNU-PR-Package: coreutils X-GNU-PR-Keywords: notabug To: =?UTF-8?Q?P=C3=A1draig?= Brady Cc: 15680@debbugs.gnu.org Reply-To: Bernhard Voelker Received: via spool by 15680-submit@debbugs.gnu.org id=B15680.138244766819233 (code B ref 15680); Tue, 22 Oct 2013 13:15:03 +0000 Received: (at 15680) by debbugs.gnu.org; 22 Oct 2013 13:14:28 +0000 Received: from localhost ([127.0.0.1]:34743 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1VYbn0-000508-NS for submit@debbugs.gnu.org; Tue, 22 Oct 2013 09:14:27 -0400 Received: from moutng.kundenserver.de ([212.227.17.9]:57401) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1VYbmx-0004zu-Qr for 15680@debbugs.gnu.org; Tue, 22 Oct 2013 09:14:24 -0400 Received: from oxbaltgw10.schlund.de (oxbaltgw10.schlund.de [172.19.246.16]) by mrelayeu.kundenserver.de (node=mreu0) with ESMTP (Nemesis) id 0LsdiP-1VjuUq0Y5h-011xol; Tue, 22 Oct 2013 15:14:17 +0200 Date: Tue, 22 Oct 2013 15:14:17 +0200 (CEST) From: Bernhard Voelker Message-ID: <374824287.443347.1382447657148.open-xchange@email.1und1.de> In-Reply-To: <52665B6E.6020608@draigBrady.com> References: <52661F96.9080402@bernhard-voelker.de> <5266449D.8030905@draigBrady.com> <1221012425.432486.1382437588425.open-xchange@email.1und1.de> <52665B6E.6020608@draigBrady.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Priority: 3 Importance: Medium X-Mailer: Open-Xchange Mailer v7.2.2-Rev20 X-Provags-ID: V02:K0:MR5782Lk3TY26dIp2mifttsLGwcz97uIMFuoY/q1xkT j0yN+nf0SYn6i8pPIhh/czRAlCF52eHuftp5LwjqXlI4WiVDyh DhH9G94vGuQw+Z81TFKJPS3v61iiPOQRu2+U+lKx9gMXR90LFa CMwQD7I8srLZ6JVDIaSGx79VBFdxX3ZzysviyUSWtz4Wecd658 h+PRtZX3x0j5L4GcLEaBjseetkvHayKqviLraq8rjyBpH9ITFP i8BWT+JGq9RbQlayzYv5dcKEXb6ip27Q803we6s8u3uAfA1GV6 m9NsnFCA42IQG1n0cdx3Q2e6BzW8u48usVdy3Mns4HUM69pfw8 KY6enIbOoIrullGnfnZcVu8sc0cvC6GOwQp98RBKZGyMvMlfS+ c82Wdb//W+g/3QY7gua7765znXcgDAs9uo= X-Spam-Score: -0.0 (/) X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: debbugs-submit-bounces@debbugs.gnu.org Sender: "Debbugs-submit" X-Spam-Score: -0.0 (/) >=C2=A0On=C2=A0October=C2=A022,=C2=A02013=C2=A0at=C2=A01:03=C2=A0PM=C2=A0P= =C3=A1draig=C2=A0Brady=C2=A0=C2=A0wrote: >=C2=A0On=C2=A010/22/2013=C2=A011:26=C2=A0AM,=C2=A0Bernhard=C2=A0Voelker=C2= =A0wrote: >=C2=A0>=C2=A0To=C2=A0avoid=C2=A0that=C2=A0this=C2=A0question=C2=A0comes=C2= =A0up=C2=A0again:=C2=A0should=C2=A0we=C2=A0add >=C2=A0>=C2=A0this=C2=A0into=C2=A0the=C2=A0Texinfo=C2=A0file? >=C2=A0 >=C2=A0Maybe,=C2=A0though=C2=A0we=C2=A0have=C2=A0to=C2=A0be=C2=A0careful=C2= =A0of=C2=A0coupling=C2=A0the >=C2=A0docs=C2=A0too=C2=A0tightly=C2=A0with=C2=A0the=C2=A0code. >=C2=A0Worth=C2=A0a=C2=A0source=C2=A0comment=C2=A0at=C2=A0least. Ctually, this question came up on a discussion on the opensuse-factory mailing list [1]. It'd be good to be able to point end users to some documentation they can easily access.=C2=A0 Therefore, I thought that the info pages would be the right place. WDYT? [1] http://lists.opensuse.org/opensuse-factory/2013-10/msg00565.html Have a nice day, Berny From unknown Mon Aug 18 11:33:03 2025 X-Loop: help-debbugs@gnu.org Subject: bug#15680: dd: suggest iflag=fullblock ... but only if count > 1 Resent-From: =?UTF-8?Q?P=C3=A1draig?= Brady Original-Sender: "Debbugs-submit" Resent-CC: bug-coreutils@gnu.org Resent-Date: Tue, 22 Oct 2013 15:30:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 15680 X-GNU-PR-Package: coreutils X-GNU-PR-Keywords: notabug To: Bernhard Voelker Cc: 15680@debbugs.gnu.org Received: via spool by 15680-submit@debbugs.gnu.org id=B15680.138245579732397 (code B ref 15680); Tue, 22 Oct 2013 15:30:02 +0000 Received: (at 15680) by debbugs.gnu.org; 22 Oct 2013 15:29:57 +0000 Received: from localhost ([127.0.0.1]:35309 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1VYdu8-0008QQ-0n for submit@debbugs.gnu.org; Tue, 22 Oct 2013 11:29:56 -0400 Received: from mail6.vodafone.ie ([213.233.128.184]:55974) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1VYdu4-0008Q8-0K for 15680@debbugs.gnu.org; Tue, 22 Oct 2013 11:29:53 -0400 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: ApUBAIaZZlJtTvAx/2dsb2JhbAANTIM/g366U0uBO4MZAQEBBAECIA8BOwsQCw0BCgICBRYLAgIJAwIBAgEWLwYNAQUCAQEFiAIIpnV1klOBKY4lB4JqgT8DlTyDfIUzjko Received: from unknown (HELO [192.168.1.79]) ([109.78.240.49]) by mail3.vodafone.ie with ESMTP; 22 Oct 2013 16:29:45 +0100 Message-ID: <526699E8.1090000@draigBrady.com> Date: Tue, 22 Oct 2013 16:29:44 +0100 From: =?UTF-8?Q?P=C3=A1draig?= Brady User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130110 Thunderbird/17.0.2 MIME-Version: 1.0 References: <52661F96.9080402@bernhard-voelker.de> <5266449D.8030905@draigBrady.com> <1221012425.432486.1382437588425.open-xchange@email.1und1.de> <52665B6E.6020608@draigBrady.com> <374824287.443347.1382447657148.open-xchange@email.1und1.de> In-Reply-To: <374824287.443347.1382447657148.open-xchange@email.1und1.de> X-Enigmail-Version: 1.5.2 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Spam-Score: 0.0 (/) X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: debbugs-submit-bounces@debbugs.gnu.org Sender: "Debbugs-submit" X-Spam-Score: 0.0 (/) On 10/22/2013 02:14 PM, Bernhard Voelker wrote: >> On October 22, 2013 at 1:03 PM Pádraig Brady wrote: >> On 10/22/2013 11:26 AM, Bernhard Voelker wrote: >> > To avoid that this question comes up again: should we add >> > this into the Texinfo file? >> >> Maybe, though we have to be careful of coupling the >> docs too tightly with the code. >> Worth a source comment at least. > > Ctually, this question came up on a discussion on the > opensuse-factory mailing list [1]. > It'd be good to be able to point end users to some documentation > they can easily access. Therefore, I thought that the info > pages would be the right place. > WDYT? > > [1] http://lists.opensuse.org/opensuse-factory/2013-10/msg00565.html That thread could just link to: http://www.gnu.org/software/coreutils/manual/html_node/dd-invocation.html and the count= description which references iflag=fullblock, should explain the short read situation adequately I think? The runtime warning conditions were chosen to be conservative, and only trigger when a short read is confirmed to have occurred, in a probably unintended situation, rather than flagging potential issues with different inputs files etc. Now we might add various extra up front messages about potential gotchas in dd usage when conv=debug was specified (akin to sort --debug). Given that I have trouble remembering the edge cases sometimes (like I did for sort), it might be worth adding. thanks, Pádraig.