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Date: Tue, 27 May 2003 23:03:49 -0700
From: Terry Lambert <tlambert2@mindspring.com>
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To: Igor Sysoev <is@rambler-co.ru>
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Subject: Re: sendfile(2) SF_NOPUSH flag proposal
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Igor Sysoev wrote:
> > I don't think overhead is the issue, at this point: say we agree
> > with you on overhead, for your particular application, and we are
> > not against you solving your overhead problem: why exactly does
> > the API have to change to fix the root cause of the problem?
> 
> I do not propose the change of the API, I propose the source and binary
> compatible addition.

The "Subject:" line says you want to add a flag.  This is
binary backward compatible, but it is not binary portable,
and it is not source portable to systems that use your flag.

What happens when you want to recompile or run your code
that uses the new flag on NetBSD, Darwin, MacOS X, etc.?

I'll tell you what happens: you get a compilation error
with an undefined variable.

-- Terry