From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933104Ab3EOUs5 (ORCPT ); Wed, 15 May 2013 16:48:57 -0400 Received: from mail3.vodafone.ie ([213.233.128.45]:42083 "EHLO mail3.vodafone.ie" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932698Ab3EOUs4 (ORCPT ); Wed, 15 May 2013 16:48:56 -0400 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AkIDAPPzk1FtTvCU/2dsb2JhbAANNBqDPkSCeL0ZAwGBE4MTAQEBAwEjDwE/BxALDQEKAgIFIQICDwJGBgEMAQcBAYgCDQUzqhBykVKBJo0ZXweCQoETA5hchReFXogx Message-ID: <5193F4B5.500@draigBrady.com> Date: Wed, 15 May 2013 21:48:53 +0100 From: =?UTF-8?B?UMOhZHJhaWcgQnJhZHk=?= User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130110 Thunderbird/17.0.2 MIME-Version: 1.0 To: Eric Blake , linux-api@vger.kernel.org, Alexander Viro CC: linux-kernel@vger.kernel.org Subject: Re: RFC: allow empty symlink targets References: <1358427833-3847-1-git-send-email-P@draigBrady.com> <50F8252C.2060404@draigBrady.com> <519381D8.5080206@draigBrady.com> <51939E49.1040209@redhat.com> In-Reply-To: <51939E49.1040209@redhat.com> X-Enigmail-Version: 1.5.1 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 05/15/2013 03:40 PM, Eric Blake wrote: > On 05/15/2013 06:38 AM, Pádraig Brady wrote: >> On 01/17/2013 04:22 PM, Pádraig Brady wrote: >>> On 01/17/2013 01:03 PM, Pádraig Brady wrote: >>>> The discussion leading to this is at http://bugs.gnu.org/13447 >>>> In summary other systems allow an empty target for a symlink, >>>> and POSIX specifies that it should be allowed? >>> >>> In relation to this, Eric Blake said: >>> >>>> In today's Austin Group meeting, I was tasked to open a new bug that >>>> would state specifically how the empty symlink is resolved; the intent >>>> is to allow both Solaris behavior (current directory) and BSD behavior >>>> (ENOENT). Meanwhile, everyone was in agreement that the Linux kernel >>>> has a bug for rejecting the creation of an empty symlink, but once that >>>> bug is fixed, then Linux can choose either Solaris or BSD behavior for >>>> how to resolve such a symlink. >>>> >>>> It will probably be a bug report similar to this one, which regarded how >>>> to handle a symlink containing just slashes: >>>> http://austingroupbugs.net/view.php?id=541 >> >> Following up from http://austingroupbugs.net/view.php?id=649 >> It seems POSIX will now allow the current Linux behavior of returning ENOENT, > > Huh? Linux currently doesn't allow the creation of an empty symlink. > That link mentions the current BSD behavior of returning ENOENT when > resolving such a symlink (that is, what stat() does when chasing through > an empty symlink, provided such a symlink is first created). Ah OK. The standards are hard enough to interpret, never mind the comments discussing the standards :) Not helping was that symlink() returns ENOENT in this case too. >> or the Solaris behavior of allowing empty symlink targets. > > The point made in that bug report is that Linux is buggy for not > allowing symlink() to create an empty symlink in the first place; once > you allow the creation of an empty symlink, then how to handle such a > symlink in stat() is up to you whether to copy Solaris' or BSD's example. OK cool, that make more sense to me. Adding in a couple more recipients to garner interest... thanks, Pádraig.