Re: Linux-only fdatasync() in 3c13bc

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+Date: Wed, 7 May 2014 13:18:36 -0400\r
+From: Austin Clements <amdragon@MIT.EDU>\r
+To: David Bremner <david@tethera.net>\r
+Subject: Re: Linux-only fdatasync() in 3c13bc\r
+Message-ID: <20140507171835.GA27619@mit.edu>\r
+References: <20140506195938.GA18213@coyotlan.Tlalpan>\r
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+Cc: Tomi Ollila <tomi.ollila@iki.fi>, notmuch@notmuchmail.org\r
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+\r
+Quoth David Bremner on May 07 at 10:17 pm:\r
+> Tomi Ollila <tomi.ollila@iki.fi> writes:\r
+> \r
+> > On Wed, May 07 2014, Kushal Kumaran <kushal.kumaran+notmuch@gmail.com> wrote:\r
+> >\r
+> >> Xīcò <xico@atelo.org> writes:\r
+> >>\r
+> >>> Also, commit 3c13bc introduced a call to fdatasync() which is not\r
+> >>> available on FreeBSD, and probably not either on MacOS at least.\r
+> >>>\r
+> >>\r
+> >> fdatasync is POSIX:\r
+> >> http://pubs.opengroup.org/onlinepubs/009695399/functions/fdatasync.html\r
+> >\r
+> > No wonder it is problematic, then >;)\r
+> >\r
+> \r
+> I seem to recall Austin saying on IRC that this usage was guaranteed to\r
+> call fsync anyway. Comments Austin?\r
+\r
+Yes, since the size of the file will have definitely changed, the\r
+metadata will have to be flushed anyway, so using fdatasync here has\r
+no advantage over using fsync.\r