From owner-freebsd-hackers@FreeBSD.ORG  Wed Apr 21 12:23:25 2004
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Date: Wed, 21 Apr 2004 12:23:20 -0700 (PDT)
From: Julian Elischer <julian@elischer.org>
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Subject: how to flush out cache.?
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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)