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Date: Tue, 9 Jan 1996 14:43:04 -0500 (EST)
From: "Ron G. Minnich" <rminnich@Sarnoff.COM>
To: Jaye Mathisen <mrcpu@cdsnet.net>
cc: John Beukema <john@gateway.net.hk>, hackers@freebsd.org
Subject: mmap issue with vm/file system 
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As things stand now, in 2.1, you can't mmap a file and assume that you'll
get the same results from a series of loads/stores as from a series of
reads/writes. The vm and file system integration is still not there,
although I understand john dyson and co. are working very hard on getting
it done. But once it does work the release number will be > 2.1.  That's
not to say that you can't use shared mapped files for some uses, it's just
that you can't expect it to be integrated correctly with file I/O.

freebsd is not alone in this: xxxbsd doesn't do it yet, and from my 
several tries at it linux doesn't get it right either. 

Ron Minnich                |Like a knife through Daddy's heart: 
rminnich@sarnoff.com       |"Don't make fun of Windows, daddy! It takes care
(609)-734-3120             | of all my files and it's reliable and I like it".