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Date: Mon, 31 Mar 2008 21:57:39 +0100
From: James Mansion <james@mansionfamily.plus.com>
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To: Mark Mielke <mark@mark.mielke.cc>
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Subject: Re: POSIX file updates
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> I don't believe POSIX has any restriction such as you describe - or if 
> it does, and I don't know about it, then most UNIX file systems (if 
> not most file systems on any platform) are not POSIX compliant.
>
I suspect that indeed there are two different issues here in that the 
file mutex relates to updates
to the file, not passing the buffers through into the drive, which 
indeed might be delayed.

Been using direct io too much recently. :-(