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To: Julian Elischer <julian@elischer.org>
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Date: Wed, 21 Apr 2004 17:21:58 -0400
From: Stephan Uphoff <ups@tree.com>
cc: hackers@freebsd.org
Subject: Re: how to flush out cache.? 
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mmap() and msync(..MS_INVALIDATE..) should work.

	Stephan

> 
> Ok so I have an application where I need to 
> reread a file I have just written to ensure that it went to disk
> correctly..
> 
> Other than reading a few GB of data, is there a way to flush
> out the cache copy of a file I've written?
> 
> possibilities include:
> 
> a file flag saying "don't keep a copy after it's written to disk"?
> a syscall discard_cached_blocks(fd);
> 
> 
> ?
> any other suggestions?
> 
> julian
> (BTW this would be for 4.x initially)
> 
> 
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