From debbugs-submit-bounces@debbugs.gnu.org Sun Mar 23 17:21:15 2014 Received: (at submit) by debbugs.gnu.org; 23 Mar 2014 21:21:15 +0000 Received: from localhost ([127.0.0.1]:46288 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WRppS-0002jM-KI for submit@debbugs.gnu.org; Sun, 23 Mar 2014 17:21:14 -0400 Received: from eggs.gnu.org ([208.118.235.92]:39807) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WRppQ-0002jD-Gk for submit@debbugs.gnu.org; Sun, 23 Mar 2014 17:21:12 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WRppI-0001v9-3p for submit@debbugs.gnu.org; Sun, 23 Mar 2014 17:21:12 -0400 X-Spam-Checker-Version: SpamAssassin 3.3.2 (2011-06-06) on eggs.gnu.org X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=disabled version=3.3.2 Received: from lists.gnu.org ([2001:4830:134:3::11]:43722) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WRppI-0001v5-0Y for submit@debbugs.gnu.org; Sun, 23 Mar 2014 17:21:04 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:41445) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WRppC-0002Pl-0t for bug-diffutils@gnu.org; Sun, 23 Mar 2014 17:21:03 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WRpp5-0001tB-T4 for bug-diffutils@gnu.org; Sun, 23 Mar 2014 17:20:57 -0400 Received: from frenzy.freefriends.org ([66.54.153.139]:42402 helo=freefriends.org) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WRpp5-0001sV-Mb for bug-diffutils@gnu.org; Sun, 23 Mar 2014 17:20:51 -0400 X-Envelope-From: karl@freefriends.org X-Envelope-To: Received: from freefriends.org (localhost [127.0.0.1]) by freefriends.org (8.14.8/8.14.8) with ESMTP id s2NLKl5h018917 for ; Sun, 23 Mar 2014 15:20:47 -0600 Received: (from nobody@localhost) by freefriends.org (8.14.8/8.14.8/submit) id s2NLKlVe018916; Sun, 23 Mar 2014 21:20:47 GMT Date: Sun, 23 Mar 2014 21:20:47 GMT Message-Id: <201403232120.s2NLKlVe018916@freefriends.org> X-Authentication-Warning: frenzy.freefriends.org: nobody set sender to karl@freefriends.org using -f From: karl@freefriends.org (Karl Berry) To: bug-diffutils@gnu.org Subject: diff - - exits immediately X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x 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-Debbugs-Envelope-To: submit 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 (-----) With diff 3.3, running diff - - exits immediately, and successfully, for me. (Compiled from the original GNU source, running on CentOS 6.5.) It seems like it should either read stdin twice (probably too much trouble), or read stdin once and then abort when it can't be read again, or just abort immediately. Or something, just not success. FWIW ... karl From debbugs-submit-bounces@debbugs.gnu.org Sun Mar 23 17:47:24 2014 Received: (at 17075) by debbugs.gnu.org; 23 Mar 2014 21:47:24 +0000 Received: from localhost ([127.0.0.1]:46306 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WRqEk-0003Qu-W9 for submit@debbugs.gnu.org; Sun, 23 Mar 2014 17:47:23 -0400 Received: from smtp.cs.ucla.edu ([131.179.128.62]:55737) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WRqEi-0003Qe-MS for 17075@debbugs.gnu.org; Sun, 23 Mar 2014 17:47:21 -0400 Received: from localhost (localhost.localdomain [127.0.0.1]) by smtp.cs.ucla.edu (Postfix) with ESMTP id EAAF639E8012; Sun, 23 Mar 2014 14:47:14 -0700 (PDT) X-Virus-Scanned: amavisd-new at smtp.cs.ucla.edu Received: from smtp.cs.ucla.edu ([127.0.0.1]) by localhost (smtp.cs.ucla.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Jgd+l0LJj4A9; Sun, 23 Mar 2014 14:47:14 -0700 (PDT) Received: from [192.168.1.9] (pool-108-0-233-62.lsanca.fios.verizon.net [108.0.233.62]) by smtp.cs.ucla.edu (Postfix) with ESMTPSA id 6A3F339E8008; Sun, 23 Mar 2014 14:47:14 -0700 (PDT) Message-ID: <532F5661.9060703@cs.ucla.edu> Date: Sun, 23 Mar 2014 14:47:13 -0700 From: Paul Eggert Organization: UCLA Computer Science Department User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.4.0 MIME-Version: 1.0 To: Karl Berry , 17075@debbugs.gnu.org Subject: Re: [bug-diffutils] bug#17075: diff - - exits immediately References: <201403232120.s2NLKlVe018916@freefriends.org> In-Reply-To: <201403232120.s2NLKlVe018916@freefriends.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Score: -2.8 (--) X-Debbugs-Envelope-To: 17075 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: -2.8 (--) Karl Berry wrote: > It seems like it should either read stdin twice (probably too much > trouble), or read stdin once and then abort when it can't be read again, > or just abort immediately. Or something, just not success. I don't see why 'diff' should be prohibited from optimizing the case 'diff A A'. 'diff' should be allowed to read 'A' just once (or even not at all, which is what 'diff' actually does). '-' is just a special case of this. From debbugs-submit-bounces@debbugs.gnu.org Mon Mar 24 08:33:59 2014 Received: (at 17075) by debbugs.gnu.org; 24 Mar 2014 12:33:59 +0000 Received: from localhost ([127.0.0.1]:46776 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WS44l-0000c8-37 for submit@debbugs.gnu.org; Mon, 24 Mar 2014 08:33:59 -0400 Received: from mx1.redhat.com ([209.132.183.28]:46643) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WS44h-0000bw-73 for 17075@debbugs.gnu.org; Mon, 24 Mar 2014 08:33:57 -0400 Received: from int-mx12.intmail.prod.int.phx2.redhat.com (int-mx12.intmail.prod.int.phx2.redhat.com [10.5.11.25]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id s2OCXqxD009146 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Mon, 24 Mar 2014 08:33:52 -0400 Received: from [10.3.113.70] (ovpn-113-70.phx2.redhat.com [10.3.113.70]) by int-mx12.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id s2OCXpfO004394; Mon, 24 Mar 2014 08:33:52 -0400 Message-ID: <5330262F.2070305@redhat.com> Date: Mon, 24 Mar 2014 06:33:51 -0600 From: Eric Blake Organization: Red Hat, Inc. User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.3.0 MIME-Version: 1.0 To: Paul Eggert , Karl Berry , 17075@debbugs.gnu.org Subject: Re: [bug-diffutils] bug#17075: bug#17075: diff - - exits immediately References: <201403232120.s2NLKlVe018916@freefriends.org> <532F5661.9060703@cs.ucla.edu> In-Reply-To: <532F5661.9060703@cs.ucla.edu> 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="T3Tv47hpkBPNKF1aAqPapquaX5HhQ0mxm" X-Scanned-By: MIMEDefang 2.68 on 10.5.11.25 X-Spam-Score: -5.5 (-----) X-Debbugs-Envelope-To: 17075 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: -5.5 (-----) This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --T3Tv47hpkBPNKF1aAqPapquaX5HhQ0mxm Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On 03/23/2014 03:47 PM, Paul Eggert wrote: > Karl Berry wrote: >> It seems like it should either read stdin twice (probably too much >> trouble), or read stdin once and then abort when it can't be read agai= n, >> or just abort immediately. Or something, just not success. >=20 > I don't see why 'diff' should be prohibited from optimizing the case > 'diff A A'. 'diff' should be allowed to read 'A' just once (or even no= t > at all, which is what 'diff' actually does). '-' is just a special cas= e > of this. POSIX states in XCU 1.4: http://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap01.html Unless otherwise stated, the use of multiple instances of '-' to mean standard input in a single command produces unspecified results. and its description for 'diff' does not place any other requirements on double '-', so we are free to behave however we want. I personally think that special-casing '-' to read stdin twice makes more sense, at least when fstat(0) says that stdin is not a regular file (the way that 'cat - -' behaves differently for stdin used twice). I agree with the optimization of not reading a file at all if we know the argument is not '-', or if the argument is '-' but fstat(0) says the file is regular. --=20 Eric Blake eblake redhat com +1-919-301-3266 Libvirt virtualization library http://libvirt.org --T3Tv47hpkBPNKF1aAqPapquaX5HhQ0mxm 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 Comment: Public key at http://people.redhat.com/eblake/eblake.gpg Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iQEcBAEBCAAGBQJTMCYvAAoJEKeha0olJ0Nq3pUH/0qsMJzbmQRR0nRcyPfD7l5n ON+JLOoHs3QooOU5rIa9adwSVY6yz1JTfSeNlEL9dkvKsqQ54nF2TPj6ZnZCwsoo na2D3f0+rPL7DcBmSzlHU1c3yEjfdiO2Zo6tuIrwFMWkxkh2ryH+ggvC+ivajdeX 3k0VICF2UPXRh7+bmw7yY3YQ25Z251ti9aAivZ6H7ncK292GQvmgTsIup2faqejf U4WFx7EgcGr486FD9nPR8lo+RDPhBD5Xgy7xc7xz8TlpsBm4D4C9gkgScJrM3hE0 l8aMe6jSAzDCRIwRx1XHLn8+hKIXZQz5SCyUFGzvrRLzox475rGgCTdW0WOSAMY= =Yqx8 -----END PGP SIGNATURE----- --T3Tv47hpkBPNKF1aAqPapquaX5HhQ0mxm-- From debbugs-submit-bounces@debbugs.gnu.org Mon Mar 24 11:27:21 2014 Received: (at 17075) by debbugs.gnu.org; 24 Mar 2014 15:27:21 +0000 Received: from localhost ([127.0.0.1]:47775 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WS6mW-0005XH-LV for submit@debbugs.gnu.org; Mon, 24 Mar 2014 11:27:20 -0400 Received: from smtp.cs.ucla.edu ([131.179.128.62]:34472) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WS6mU-0005X7-N6 for 17075@debbugs.gnu.org; Mon, 24 Mar 2014 11:27:19 -0400 Received: from localhost (localhost.localdomain [127.0.0.1]) by smtp.cs.ucla.edu (Postfix) with ESMTP id 44ABFA60002; Mon, 24 Mar 2014 08:27:18 -0700 (PDT) X-Virus-Scanned: amavisd-new at smtp.cs.ucla.edu Received: from smtp.cs.ucla.edu ([127.0.0.1]) by localhost (smtp.cs.ucla.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 3M+JgfZbLIey; Mon, 24 Mar 2014 08:27:17 -0700 (PDT) Received: from [192.168.1.9] (pool-108-0-233-62.lsanca.fios.verizon.net [108.0.233.62]) by smtp.cs.ucla.edu (Postfix) with ESMTPSA id CF8E5A60001; Mon, 24 Mar 2014 08:27:17 -0700 (PDT) Message-ID: <53304ED5.5020808@cs.ucla.edu> Date: Mon, 24 Mar 2014 08:27:17 -0700 From: Paul Eggert Organization: UCLA Computer Science Department User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.4.0 MIME-Version: 1.0 To: Eric Blake , Karl Berry , 17075@debbugs.gnu.org Subject: Re: [bug-diffutils] bug#17075: bug#17075: diff - - exits immediately References: <201403232120.s2NLKlVe018916@freefriends.org> <532F5661.9060703@cs.ucla.edu> <5330262F.2070305@redhat.com> In-Reply-To: <5330262F.2070305@redhat.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Score: -2.8 (--) X-Debbugs-Envelope-To: 17075 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: -2.8 (--) Eric Blake wrote: > special-casing '-' to read stdin twice makes more sense, at > least when fstat(0) says that stdin is not a regular file (the way that > 'cat - -' behaves differently for stdin used twice). The difference in behavior is inherent to what the two commands need to do. 'cat - -' must read standard input, whereas 'diff - -' needn't. It's like 'cmp -s - -'. Here's another difference, which is also OK: 'diff -q - /etc/passwd' need not read standard input until EOF. It can simply read stdin until it finds a difference, just as 'cmp -s - /etc/passwd' can. 'cat - /etc/passwd' doesn't have that liberty. From debbugs-submit-bounces@debbugs.gnu.org Mon Mar 24 14:10:30 2014 Received: (at 17075) by debbugs.gnu.org; 24 Mar 2014 18:10:30 +0000 Received: from localhost ([127.0.0.1]:47957 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WS9KP-0004Hl-AZ for submit@debbugs.gnu.org; Mon, 24 Mar 2014 14:10:29 -0400 Received: from frenzy.freefriends.org ([66.54.153.139]:46710 helo=freefriends.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WS9KM-0004Ha-GZ for 17075@debbugs.gnu.org; Mon, 24 Mar 2014 14:10:27 -0400 X-Envelope-From: karl@freefriends.org Received: from freefriends.org (localhost [127.0.0.1]) by freefriends.org (8.14.8/8.14.8) with ESMTP id s2OIAJfT020882; Mon, 24 Mar 2014 12:10:19 -0600 Received: (from nobody@localhost) by freefriends.org (8.14.8/8.14.8/submit) id s2OIAJal020881; Mon, 24 Mar 2014 18:10:19 GMT Date: Mon, 24 Mar 2014 18:10:19 GMT Message-Id: <201403241810.s2OIAJal020881@freefriends.org> X-Authentication-Warning: frenzy.freefriends.org: nobody set sender to karl@freefriends.org using -f From: karl@freefriends.org (Karl Berry) To: eggert@cs.ucla.edu Subject: Re: [bug-diffutils] bug#17075: diff - - exits immediately In-Reply-To: <532F5661.9060703@cs.ucla.edu> X-Spam-Score: -0.5 (/) X-Debbugs-Envelope-To: 17075 Cc: 17075@debbugs.gnu.org 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: -0.5 (/) diff A A Couldn't there be side effects missed by not reading the input? E.g., if stdin is a pipe, or maybe a named pipes, or special file. Doesn't seem equivalent to regular files to me, as Eric says. Anyway, I won't argue for a change in behavior. I was just surprised that stdin was not read at all. Perhaps the help message could get a one-line addition: < If a FILE is '-', read standard input. - > If a FILE is '-', read standard input. > If FILES are identical strings, nothing is read. Not sure that's exactly right, but it's the best my brain can do right now. The manual explicitly says: As a special case, `diff - -' compares a copy of standard input to itself. That does not seem accurate to me (perhaps it was once). It doesn't read stdin at all, it just exits zero immediately. Not that any of this is a big deal, of course. thanks, karl From debbugs-submit-bounces@debbugs.gnu.org Mon Mar 24 20:06:14 2014 Received: (at 17075) by debbugs.gnu.org; 25 Mar 2014 00:06:14 +0000 Received: from localhost ([127.0.0.1]:48213 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WSEsg-0007tf-5K for submit@debbugs.gnu.org; Mon, 24 Mar 2014 20:06:14 -0400 Received: from smtp.cs.ucla.edu ([131.179.128.62]:36651) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WSEsd-0007tT-Va for 17075@debbugs.gnu.org; Mon, 24 Mar 2014 20:06:12 -0400 Received: from localhost (localhost.localdomain [127.0.0.1]) by smtp.cs.ucla.edu (Postfix) with ESMTP id A159539E8016; Mon, 24 Mar 2014 17:06:10 -0700 (PDT) X-Virus-Scanned: amavisd-new at smtp.cs.ucla.edu Received: from smtp.cs.ucla.edu ([127.0.0.1]) by localhost (smtp.cs.ucla.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id y+-Ndhr+u+Nn; Mon, 24 Mar 2014 17:06:10 -0700 (PDT) Received: from [192.168.1.9] (pool-108-0-233-62.lsanca.fios.verizon.net [108.0.233.62]) by smtp.cs.ucla.edu (Postfix) with ESMTPSA id ECF5F39E8008; Mon, 24 Mar 2014 17:06:09 -0700 (PDT) Message-ID: <5330C86D.50006@cs.ucla.edu> Date: Mon, 24 Mar 2014 17:06:05 -0700 From: Paul Eggert Organization: UCLA Computer Science Department User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.4.0 MIME-Version: 1.0 To: Karl Berry Subject: Re: [bug-diffutils] bug#17075: diff - - exits immediately References: <201403241810.s2OIAJal020881@freefriends.org> In-Reply-To: <201403241810.s2OIAJal020881@freefriends.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Score: -2.8 (--) X-Debbugs-Envelope-To: 17075 Cc: 17075@debbugs.gnu.org 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: -2.8 (--) Karl Berry wrote: > Couldn't there be side effects missed by not reading the input? Sure, but the invoker shouldn't rely on those side effects, from 'diff' or from 'cmp' or from 'head' or from any other program that need not read all its input. > Perhaps the help message could get a one-line addition: Unfortunately all the one-liners I can think of are wrong. For example, diff must read all its input even when given two identical file names A and A, e.g., if it's also given the -DFOO option. And even without -DFOO, 'diff A A' reports an error if A does not exist. Another amusing example: 'diff A A' can succeed even if A is unreadable: $ umask 777 $ echo foo >A $ ls -l A ---------- 1 eggert eggert 4 Mar 24 17:02 A $ diff A A $ echo $? 0 From debbugs-submit-bounces@debbugs.gnu.org Tue Mar 25 17:12:43 2014 Received: (at 17075) by debbugs.gnu.org; 25 Mar 2014 21:12:43 +0000 Received: from localhost ([127.0.0.1]:49722 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WSYeH-00077m-V3 for submit@debbugs.gnu.org; Tue, 25 Mar 2014 17:12:42 -0400 Received: from frenzy.freefriends.org ([66.54.153.139]:59722 helo=freefriends.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WSYeG-00077c-2n for 17075@debbugs.gnu.org; Tue, 25 Mar 2014 17:12:40 -0400 X-Envelope-From: karl@freefriends.org Received: from freefriends.org (localhost [127.0.0.1]) by freefriends.org (8.14.8/8.14.8) with ESMTP id s2PLCcUr005330; Tue, 25 Mar 2014 15:12:38 -0600 Received: (from nobody@localhost) by freefriends.org (8.14.8/8.14.8/submit) id s2PLCbRW005329; Tue, 25 Mar 2014 21:12:37 GMT Date: Tue, 25 Mar 2014 21:12:37 GMT Message-Id: <201403252112.s2PLCbRW005329@freefriends.org> X-Authentication-Warning: frenzy.freefriends.org: nobody set sender to karl@freefriends.org using -f From: karl@freefriends.org (Karl Berry) To: eggert@cs.ucla.edu Subject: Re: [bug-diffutils] bug#17075: diff - - exits immediately In-Reply-To: <5330C86D.50006@cs.ucla.edu> X-Spam-Score: -0.4 (/) X-Debbugs-Envelope-To: 17075 Cc: 17075@debbugs.gnu.org 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: -0.4 (/) Unfortunately all the one-liners I can think of are wrong. Yeah, ok, forget that. How about more than one line of explanation in the manual, then? At least to avoid the wrong implication in the manual now, even if we don't want to say anything very specific about the behavior. For instance: Given the same file name twice, @code{diff} will ordinarily immediately report success, but may or may not read the file even once, depending on other options (e.g., @code{-D}) or the situation (e.g., if the file exists). This includes the case where the file is standard input, that is, @code{diff - -}. Something ... Thanks, k From debbugs-submit-bounces@debbugs.gnu.org Tue Mar 25 19:42:28 2014 Received: (at 17075) by debbugs.gnu.org; 25 Mar 2014 23:42:28 +0000 Received: from localhost ([127.0.0.1]:49790 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WSazD-00037A-HZ for submit@debbugs.gnu.org; Tue, 25 Mar 2014 19:42:28 -0400 Received: from smtp.cs.ucla.edu ([131.179.128.62]:39159) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WSazB-000371-9R for 17075@debbugs.gnu.org; Tue, 25 Mar 2014 19:42:26 -0400 Received: from localhost (localhost.localdomain [127.0.0.1]) by smtp.cs.ucla.edu (Postfix) with ESMTP id 44B9339E8013; Tue, 25 Mar 2014 16:42:24 -0700 (PDT) X-Virus-Scanned: amavisd-new at smtp.cs.ucla.edu Received: from smtp.cs.ucla.edu ([127.0.0.1]) by localhost (smtp.cs.ucla.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 6+afHMwj7GX9; Tue, 25 Mar 2014 16:42:24 -0700 (PDT) Received: from [192.168.1.9] (pool-108-0-233-62.lsanca.fios.verizon.net [108.0.233.62]) by smtp.cs.ucla.edu (Postfix) with ESMTPSA id E45E839E8008; Tue, 25 Mar 2014 16:42:23 -0700 (PDT) Message-ID: <5332145B.4010308@cs.ucla.edu> Date: Tue, 25 Mar 2014 16:42:19 -0700 From: Paul Eggert Organization: UCLA Computer Science Department User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.4.0 MIME-Version: 1.0 To: Karl Berry Subject: Re: [bug-diffutils] bug#17075: diff - - exits immediately References: <201403252112.s2PLCbRW005329@freefriends.org> In-Reply-To: <201403252112.s2PLCbRW005329@freefriends.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Score: -2.7 (--) X-Debbugs-Envelope-To: 17075 Cc: 17075@debbugs.gnu.org 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: -2.7 (--) I dunno, even that sounds dubious, as it's incomplete. For example, when A and B are different files, 'diff -q A B' reads neither A nor B if it determines via the 'stat' syscall that the files are different sizes. More generally, I'm not sure it's necessary or wise to describe exactly the optimizations 'diff' uses to avoid reading files. Quite possibly, though, I'm not understanding the problem that caused you to file the bug report in the first place. From debbugs-submit-bounces@debbugs.gnu.org Tue Mar 25 19:55:36 2014 Received: (at 17075) by debbugs.gnu.org; 25 Mar 2014 23:55:36 +0000 Received: from localhost ([127.0.0.1]:49796 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WSbBw-0003UY-4S for submit@debbugs.gnu.org; Tue, 25 Mar 2014 19:55:36 -0400 Received: from frenzy.freefriends.org ([66.54.153.139]:60984 helo=freefriends.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WSbBt-0003UO-L7 for 17075@debbugs.gnu.org; Tue, 25 Mar 2014 19:55:34 -0400 X-Envelope-From: karl@freefriends.org Received: from freefriends.org (localhost [127.0.0.1]) by freefriends.org (8.14.8/8.14.8) with ESMTP id s2PNtVA4013088; Tue, 25 Mar 2014 17:55:32 -0600 Received: (from karl@localhost) by freefriends.org (8.14.8/8.14.8/submit) id s2PNtVhC013087; Tue, 25 Mar 2014 23:55:31 GMT From: Karl Berry To: Paul Eggert Subject: Re: [bug-diffutils] bug#17075: diff - - exits immediately In-Reply-To: <5332145B.4010308@cs.ucla.edu> (message from Paul Eggert on Tue, 25 Mar 2014 16:42:19 -0700) Date: Tue, 25 Mar 2014 17:55:31 -0600 Message-ID: <86fvm5j0jw.fsf@frenzy.freefriends.org> MIME-Version: 1.0 Content-Type: text/plain X-Spam-Score: -0.4 (/) X-Debbugs-Envelope-To: 17075 Cc: 17075@debbugs.gnu.org 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: -0.4 (/) though, I'm not understanding the problem that caused you to file the bug report in the first place. I was surprised that "diff - -" did not read stdin. Sure, what I wrote is incomplete; completeness wasn't the goal (and surely isn't desired). Avoiding user surprise was the goal. Here is the one sentence in the manual which I think should be changed, regardless of anything else: As a special case, `diff - -' compares a copy of standard input to itself. I suppose some torturous interpretation could be made to consider that technically not false, but the straightforward implication is that it reads stdin. Even just deleting the sentence and replacing it with nothing would be better than leaving it, seems to me. But I think it would be better to say *something* about the fact that diff does not always read its input, in the event that it can determine the result via other methods. This is so unlike virtually every other program, as we've discussed in this thread, that I think it deserves mention. If it counts for anything, I've been using Unix for 30+ years and have worked (a tiny bit) on the diff source, the diff manual, and tons of other utilities, and I was *still* surprised. best, karl From debbugs-submit-bounces@debbugs.gnu.org Tue Mar 25 19:56:04 2014 Received: (at 17075) by debbugs.gnu.org; 25 Mar 2014 23:56:04 +0000 Received: from localhost ([127.0.0.1]:49800 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WSbCO-0003Vd-Fp for submit@debbugs.gnu.org; Tue, 25 Mar 2014 19:56:04 -0400 Received: from frenzy.freefriends.org ([66.54.153.139]:60991 helo=freefriends.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WSbCL-0003VC-Nr for 17075@debbugs.gnu.org; Tue, 25 Mar 2014 19:56:02 -0400 X-Envelope-From: karl@freefriends.org Received: from freefriends.org (localhost [127.0.0.1]) by freefriends.org (8.14.8/8.14.8) with ESMTP id s2PNtwDr013119; Tue, 25 Mar 2014 17:55:58 -0600 Received: (from karl@localhost) by freefriends.org (8.14.8/8.14.8/submit) id s2PNtw3A013115; Tue, 25 Mar 2014 23:55:58 GMT From: Karl Berry To: Paul Eggert Subject: Re: [bug-diffutils] bug#17075: diff - - exits immediately In-Reply-To: <5332145B.4010308@cs.ucla.edu> (message from Paul Eggert on Tue, 25 Mar 2014 16:42:19 -0700) Date: Tue, 25 Mar 2014 17:55:57 -0600 Message-ID: <86d2h9j0j6.fsf@frenzy.freefriends.org> MIME-Version: 1.0 Content-Type: text/plain X-Spam-Score: -0.4 (/) X-Debbugs-Envelope-To: 17075 Cc: 17075@debbugs.gnu.org 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: -0.4 (/) More generally, I'm not sure it's necessary or wise to describe exactly the optimizations 'diff' uses to avoid reading files. I completely agree and that was never (intended to be) my suggestion. k From debbugs-submit-bounces@debbugs.gnu.org Tue Mar 25 21:06:58 2014 Received: (at 17075) by debbugs.gnu.org; 26 Mar 2014 01:06:58 +0000 Received: from localhost ([127.0.0.1]:49842 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WScIz-0005dN-S4 for submit@debbugs.gnu.org; Tue, 25 Mar 2014 21:06:58 -0400 Received: from smtp.cs.ucla.edu ([131.179.128.62]:42457) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WScIy-0005dF-0V for 17075@debbugs.gnu.org; Tue, 25 Mar 2014 21:06:56 -0400 Received: from localhost (localhost.localdomain [127.0.0.1]) by smtp.cs.ucla.edu (Postfix) with ESMTP id 1B59039E8017; Tue, 25 Mar 2014 18:06:55 -0700 (PDT) X-Virus-Scanned: amavisd-new at smtp.cs.ucla.edu Received: from smtp.cs.ucla.edu ([127.0.0.1]) by localhost (smtp.cs.ucla.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 5kgXup15+hrI; Tue, 25 Mar 2014 18:06:54 -0700 (PDT) Received: from [192.168.1.9] (pool-108-0-233-62.lsanca.fios.verizon.net [108.0.233.62]) by smtp.cs.ucla.edu (Postfix) with ESMTPSA id 8898239E8008; Tue, 25 Mar 2014 18:06:54 -0700 (PDT) Message-ID: <5332282D.7070901@cs.ucla.edu> Date: Tue, 25 Mar 2014 18:06:53 -0700 From: Paul Eggert Organization: UCLA Computer Science Department User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.4.0 MIME-Version: 1.0 To: Karl Berry Subject: Re: [bug-diffutils] bug#17075: diff - - exits immediately References: <86fvm5j0jw.fsf@frenzy.freefriends.org> In-Reply-To: <86fvm5j0jw.fsf@frenzy.freefriends.org> Content-Type: multipart/mixed; boundary="------------070904000401050608010604" X-Spam-Score: -2.7 (--) X-Debbugs-Envelope-To: 17075 Cc: 17075@debbugs.gnu.org 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: -2.7 (--) This is a multi-part message in MIME format. --------------070904000401050608010604 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Karl Berry wrote: > I think it would be better to say*something* about the fact that > diff does not always read its input, in the event that it can determine the > result via other methods. Thanks, that sounds good; I installed the attached. > This is so unlike virtually every other program Hmm, well, in diff's defense, lots of commonly-used programs avoid reading some or all their input in some cases, including 'grep', 'head', 'tail', 'sed', 'awk', 'dd', 'more', and 'od'. It's not just 'diff' and 'cmp'. --------------070904000401050608010604 Content-Type: text/plain; charset=UTF-8; name="0001-doc-improve-documentation-about-reading-and-stdin.patch" Content-Transfer-Encoding: base64 Content-Disposition: attachment; filename*0="0001-doc-improve-documentation-about-reading-and-stdin.patch" RnJvbSA2NTE4MzgyNDg2MWNhMTBmMzllOTM0ZDk0MGM5YmU0YjgyMWY4ZjJhIE1vbiBTZXAg MTcgMDA6MDA6MDAgMjAwMQpGcm9tOiBQYXVsIEVnZ2VydCA8ZWdnZXJ0QGNzLnVjbGEuZWR1 PgpEYXRlOiBUdWUsIDI1IE1hciAyMDE0IDE3OjU1OjI2IC0wNzAwClN1YmplY3Q6IFtQQVRD SF0gZG9jOiBpbXByb3ZlIGRvY3VtZW50YXRpb24gYWJvdXQgcmVhZGluZyBhbmQgc3RkaW4K ClNlZSBCdWcjMTcwNzUuCiogZG9jL2RpZmZ1dGlscy50ZXhpIChDb21wYXJpc29uKTogU2F5 IHRoYXQgZmlsZXMgbmVlZCBub3QgYmUgcmVhZC4KKEludm9raW5nIGRpZmYpOiBSZW1vdmUg Y29uZnVzaW5nIHJlbWFyayBhYm91dCAnZGlmZiAtIC0nLgpJdCdzIG5vdCB0aGF0IHVzZWZ1 bCwgYW5kIGl0J3Mgbm90IHBvcnRhYmxlIGFueXdheS4KLS0tCiBkb2MvZGlmZnV0aWxzLnRl eGkgfCA4ICsrKysrKy0tCiAxIGZpbGUgY2hhbmdlZCwgNiBpbnNlcnRpb25zKCspLCAyIGRl bGV0aW9ucygtKQoKZGlmZiAtLWdpdCBhL2RvYy9kaWZmdXRpbHMudGV4aSBiL2RvYy9kaWZm dXRpbHMudGV4aQppbmRleCA3YjA4Y2Q0Li4wMjJmYjhkIDEwMDY0NAotLS0gYS9kb2MvZGlm ZnV0aWxzLnRleGkKKysrIGIvZG9jL2RpZmZ1dGlscy50ZXhpCkBAIC0yMTksNiArMjE5LDEx IEBAIGdyb3VwcyBvZiBsaW5lcyB0aGF0IGRpZmZlciwgYW5kIHJlcG9ydHMgZWFjaCBncm91 cCBvZiBkaWZmZXJpbmcgbGluZXMuCiBJdHMgb3V0cHV0IGlzIGRlc2lnbmVkIHRvIG1ha2Ug aXQgZWFzeSB0byBpbnNwZWN0IHR3byBkaWZmZXJlbnQgc2V0cyBvZgogY2hhbmdlcyB0byB0 aGUgc2FtZSBmaWxlLgogCitUaGVzZSBjb21tYW5kcyBjb21wYXJlIGlucHV0IGZpbGVzIHdp dGhvdXQgbmVjZXNzYXJpbHkgcmVhZGluZyB0aGVtLgorRm9yIGV4YW1wbGUsIGlmIEBjb21t YW5ke2RpZmZ9IGlzIGFza2VkIHNpbXBseSB0byByZXBvcnQgd2hldGhlciB0d28KK2ZpbGVz IGRpZmZlciwgYW5kIGl0IGRpc2NvdmVycyB0aGF0IHRoZSBmaWxlcyBoYXZlIGRpZmZlcmVu dCBzaXplcywgaXQKK25lZWQgbm90IHJlYWQgdGhlbSB0byBkbyBpdHMgam9iLgorCiBAbWVu dQogKiBIdW5rczo6ICAgICAgICAgICAgIEdyb3VwcyBvZiBkaWZmZXJpbmcgbGluZXMuCiAq IFdoaXRlIFNwYWNlOjogICAgICAgU3VwcHJlc3NpbmcgZGlmZmVyZW5jZXMgaW4gd2hpdGUg c3BhY2UuCkBAIC0zNjcyLDggKzM2NzcsNyBAQCBkaWZmIEB2YXJ7b3B0aW9uc31AZG90c3t9 IEB2YXJ7ZmlsZXN9QGRvdHN7fQogSW4gdGhlIHNpbXBsZXN0IGNhc2UsIHR3byBmaWxlIG5h bWVzIEB2YXJ7ZnJvbS1maWxlfSBhbmQKIEB2YXJ7dG8tZmlsZX0gYXJlIGdpdmVuLCBhbmQg QGNvbW1hbmR7ZGlmZn0gY29tcGFyZXMgdGhlIGNvbnRlbnRzIG9mCiBAdmFye2Zyb20tZmls ZX0gYW5kIEB2YXJ7dG8tZmlsZX0uICBBIGZpbGUgbmFtZSBvZiBAZmlsZXstfSBzdGFuZHMg Zm9yCi10ZXh0IHJlYWQgZnJvbSB0aGUgc3RhbmRhcmQgaW5wdXQuICBBcyBhIHNwZWNpYWwg Y2FzZSwgQHNhbXB7ZGlmZiAtIC19Ci1jb21wYXJlcyBhIGNvcHkgb2Ygc3RhbmRhcmQgaW5w dXQgdG8gaXRzZWxmLgordGhlIHN0YW5kYXJkIGlucHV0LgogCiBJZiBvbmUgZmlsZSBpcyBh IGRpcmVjdG9yeSBhbmQgdGhlIG90aGVyIGlzIG5vdCwgQGNvbW1hbmR7ZGlmZn0gY29tcGFy ZXMKIHRoZSBmaWxlIGluIHRoZSBkaXJlY3Rvcnkgd2hvc2UgbmFtZSBpcyB0aGF0IG9mIHRo ZSBub24tZGlyZWN0b3J5LgotLSAKMS44LjUuMwoK --------------070904000401050608010604-- From debbugs-submit-bounces@debbugs.gnu.org Thu Mar 27 17:40:13 2014 Received: (at 17075) by debbugs.gnu.org; 27 Mar 2014 21:40:13 +0000 Received: from localhost ([127.0.0.1]:53223 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WTI21-0007Od-0u for submit@debbugs.gnu.org; Thu, 27 Mar 2014 17:40:13 -0400 Received: from frenzy.freefriends.org ([66.54.153.139]:54159 helo=freefriends.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WTI1y-0007OU-Pw for 17075@debbugs.gnu.org; Thu, 27 Mar 2014 17:40:11 -0400 X-Envelope-From: karl@freefriends.org Received: from freefriends.org (localhost [127.0.0.1]) by freefriends.org (8.14.8/8.14.8) with ESMTP id s2RLe8Nv031704; Thu, 27 Mar 2014 15:40:08 -0600 Received: (from nobody@localhost) by freefriends.org (8.14.8/8.14.8/submit) id s2RLe8Y6031703; Thu, 27 Mar 2014 21:40:08 GMT Date: Thu, 27 Mar 2014 21:40:08 GMT Message-Id: <201403272140.s2RLe8Y6031703@freefriends.org> X-Authentication-Warning: frenzy.freefriends.org: nobody set sender to karl@freefriends.org using -f From: karl@freefriends.org (Karl Berry) To: eggert@cs.ucla.edu Subject: Re: [bug-diffutils] bug#17075: diff - - exits immediately In-Reply-To: <5332282D.7070901@cs.ucla.edu> X-Spam-Score: -0.4 (/) X-Debbugs-Envelope-To: 17075 Cc: 17075@debbugs.gnu.org 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: -0.4 (/) Hmm, well, in diff's defense, lots of commonly-used programs avoid reading some or all their input in some cases, Sure. But in most other cases, the user says something to imply the partial read, e.g., it would actually be surprising in the other direction if head -10 read more than 10 lines. But head -10 - does read stdin ... anyway, I don't argue that diff is unique in this regard, only that in practice it comes up more and is more surprising when it does. Thanks for the doc patch, looks good to me. karl From debbugs-submit-bounces@debbugs.gnu.org Sun Mar 30 01:04:30 2014 Received: (at 17075-done) by debbugs.gnu.org; 30 Mar 2014 05:04:30 +0000 Received: from localhost ([127.0.0.1]:56579 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WU7v3-0002Ev-RS for submit@debbugs.gnu.org; Sun, 30 Mar 2014 01:04:30 -0400 Received: from smtp.cs.ucla.edu ([131.179.128.62]:41367) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WU7v0-0002Em-W2 for 17075-done@debbugs.gnu.org; Sun, 30 Mar 2014 01:04:27 -0400 Received: from localhost (localhost.localdomain [127.0.0.1]) by smtp.cs.ucla.edu (Postfix) with ESMTP id 300A939E8019; Sat, 29 Mar 2014 22:04:26 -0700 (PDT) X-Virus-Scanned: amavisd-new at smtp.cs.ucla.edu Received: from smtp.cs.ucla.edu ([127.0.0.1]) by localhost (smtp.cs.ucla.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 1rGovcEskGu1; Sat, 29 Mar 2014 22:04:25 -0700 (PDT) Received: from [192.168.1.9] (pool-108-0-233-62.lsanca.fios.verizon.net [108.0.233.62]) by smtp.cs.ucla.edu (Postfix) with ESMTPSA id DC5F839E8012; Sat, 29 Mar 2014 22:04:25 -0700 (PDT) Message-ID: <5337A5D9.5060003@cs.ucla.edu> Date: Sat, 29 Mar 2014 22:04:25 -0700 From: Paul Eggert Organization: UCLA Computer Science Department User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.4.0 MIME-Version: 1.0 To: Karl Berry Subject: Re: [bug-diffutils] bug#17075: diff - - exits immediately References: <201403272140.s2RLe8Y6031703@freefriends.org> In-Reply-To: <201403272140.s2RLe8Y6031703@freefriends.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Score: -2.7 (--) X-Debbugs-Envelope-To: 17075-done Cc: 17075-done@debbugs.gnu.org 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: -2.7 (--) Karl Berry wrote: > Thanks for the doc patch, looks good to me. Thanks; closing the bug report. From unknown Sat Aug 09 13:21:15 2025 Received: (at fakecontrol) by fakecontrolmessage; To: internal_control@debbugs.gnu.org From: Debbugs Internal Request Subject: Internal Control Message-Id: bug archived. Date: Sun, 27 Apr 2014 11:24:05 +0000 User-Agent: Fakemail v42.6.9 # This is a fake control message. # # The action: # bug archived. thanks # This fakemail brought to you by your local debbugs # administrator