From mboxrd@z Thu Jan  1 00:00:00 1970
From: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Subject: Re: First cut at git port to Cygwin
Date: Mon, 10 Oct 2005 21:01:31 +0200 (CEST)
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Cc: Junio C Hamano <junkio@cox.net>, git@vger.kernel.org,
	Linus Torvalds <torvalds@osdl.org>
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To: "H. Peter Anvin" <hpa@zytor.com>
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Hi,

On Mon, 10 Oct 2005, H. Peter Anvin wrote:

> Junio C Hamano wrote:
> > 
> > PROT_WRITE is true, but we do MAP_PRIVATE, and if I recall
> > correctly we do not write file via mmap -- at least we do not
> > intend to.
> > 
> 
> Then PROT_READ probably makes more sense?

Not necessarily. Sometimes you need to annotate the data from the index, 
and this does not need to be written back to the index file.

> > Yes.  It might have been overkill that you supported writing
> > changes back, though.
> 
> Not just overkill; if we do MAP_PRIVATE it's actively WRONG.

See above.

BTW, is there a mechanism to make sure that the index file is locked 
between reading and writing?

Ciao,
Dscho