[svn.haxx.se] · SVN Dev · SVN Users · SVN Org · TSVN Dev · TSVN Users · Subclipse Dev · Subclipse Users · this month's index

Re: Atomicity under Windows

From: Stephen C. Tweedie <sct_at_redhat.com>
Date: 2002-06-09 23:41:46 CEST

Hi,

On Sun, Jun 09, 2002 at 10:54:57PM +0200, Branko ?ibej wrote:
 
> I'm not sure about directory operations. You can't open a directory on
> Windows like you'd do on Unix (well, you can, but only for
> backup/restore purposes, and with the proper privileges enabled). I
> think that in the end it depends on what filesystem you're using. With
> NTFS, they should be atomic.

Right, but atomic != synchronous. A journaling filesystem can still
perform asynchronous writeback when doing a rename. You have a
guarantee that either the old or the new name will be visible after a
crash, but the atomicity guarantee alone is not enough to tell you
_when_ the new name is hard on disk. That's what you need the
additional fsync-style call for (unless the filesystem guarantees
synchronous updates as well as atomic updates.)

--Stephen

---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscribe@subversion.tigris.org
For additional commands, e-mail: dev-help@subversion.tigris.org
Received on Sun Jun 9 23:42:17 2002

This is an archived mail posted to the Subversion Dev mailing list.