X-Recipient: archive-cygwin AT delorie DOT com X-SWARE-Spam-Status: No, hits=-7.1 required=5.0 tests=AWL,BAYES_00,RCVD_IN_DNSWL_HI,RP_MATCHES_RCVD,SPF_HELO_PASS,TW_FD X-Spam-Check-By: sourceware.org Message-ID: <4E7A4C69.5080807@redhat.com> Date: Wed, 21 Sep 2011 14:43:21 -0600 From: Eric Blake User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.22) Gecko/20110906 Fedora/3.1.14-1.fc14 Lightning/1.0b3pre Mnenhy/0.8.3 Thunderbird/3.1.14 MIME-Version: 1.0 To: cygwin Subject: fsync bug Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-IsSubscribed: yes Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cygwin-owner AT cygwin DOT com Mail-Followup-To: cygwin AT cygwin DOT com Delivered-To: mailing list cygwin AT cygwin DOT com fsync() is required to work on read-only fds (in theory, you can sync the atime metadata, which is a write operation triggered by a read-only fd). But cygwin rejects this program, which works on Linux: $ cat foo.c #include #include #include #include #include #include int main (void) { int fd = open("file", O_CREAT|O_EXCL|O_WRONLY, 0600); if (fd < 0) return 1; if (close(fd)) return 2; fd = open("file", O_RDONLY); if (fd < 0) return 3; if (fsync(fd)) return 4; if (unlink("file")) return 5; puts("success"); return 0; } $ rm -f file && ./foo; echo $? 4 -- Eric Blake eblake AT redhat DOT com +1-801-349-2682 Libvirt virtualization library http://libvirt.org -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple