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Date: Fri, 16 Feb 2007 08:53:30 -0800
From: "Ray Lee" <madrabbit@gmail.com>
Reply-To: ray-gmail@madrabbit.org
To: "Evgeniy Polyakov" <johnpol@2ka.mipt.ru>
Subject: Re: [patch 05/11] syslets: core code
Cc: "Linus Torvalds" <torvalds@linux-foundation.org>,
       "Ingo Molnar" <mingo@elte.hu>,
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On 2/16/07, Evgeniy Polyakov <johnpol@2ka.mipt.ru> wrote:
> if its design is good, then
> interface can be changed in a moment without any problem

This isn't always the case. Sometimes the interface puts requirements
(contract-like) upon the implementation. Case in point in the kernel,
dnotify versus inotify. dnotify is a steaming pile of worthlessness,
because it's userspace interface is so bad (meaning inefficient) as to
be nearly unusable.

inotify has a different interface, one that supplies details about
events rather that mere notice that an event occurred, and therefore
has different requirements in implementation. dnotify probably was a
good design, but for a worthless interface.

The interface isn't always important, but it's certainly something
that has to be understood before putting the finishing touches on the
behind-the-scenes implementation.

Ray