Re: [PATCH] dump: make dump take Xapian write lock

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+From: David Bremner <david@tethera.net>\r
+To: Mark Walters <markwalters1009@gmail.com>, notmuch@notmuchmail.org\r
+Subject: Re: [PATCH] dump: make dump take Xapian write lock\r
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+References: <87zjhh67e7.fsf@qmul.ac.uk>\r
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+Mark Walters <markwalters1009@gmail.com> writes:\r
+\r
+>\r
+> Discussion with Olly on irc indicates that this is currently the best\r
+> solution: in xapian trunk there may be better possibilities using\r
+> snapshots but they need to make it to a release and propogate out to\r
+> users before we can switch approach.\r
+\r
+I agree that this seems to be the only feasible approach to make dump\r
+atomic.  I'm a little unsure about the benefits to the end user though.\r
+Currently, the user has to check the return code of dump to ensure it\r
+completed correctly.  With this change, the user will still have to\r
+check that dump did not error out when trying to acquire a write lock.\r
+The following ticket\r
+\r
+      http://trac.xapian.org/ticket/275\r
+\r
+suggests that if we wanted to a blocking open, we'd be on our own.\r
+\r
+Did I miss something here about the benefits? I agree that failing\r
+earlier is nicer, but is that it?\r
+\r
+d\r