From mboxrd@z Thu Jan  1 00:00:00 1970
From: "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: [PATCH] nextfd(2)
Date: Wed, 11 Apr 2012 10:58:24 -0700
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Cc: Alexey Dobriyan <adobriyan@gmail.com>, akpm@linux-foundation.org,
	viro@zeniv.linux.org.uk, torvalds@linux-foundation.org,
	drepper@gmail.com, linux-kernel@vger.kernel.org,
	linux-fsdevel@vger.kernel.org
To: KOSAKI Motohiro <kosaki.motohiro@gmail.com>
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On 04/10/2012 05:09 PM, KOSAKI Motohiro wrote:
> 
> I know the reason. fcntl(F_NEXT) is one of a proposal of next SUS enhancement.
> 
>   http://austingroupbugs.net/view.php?id=149
> 
> nextfd() has a semantics of F_NEXT.
> 
> Next, why shoundn't we implement fcntl(F_NEXT) in our kernel? I think
> we have two reason.
> 
> 1) As linus pointed out, linux specific "flags" argument may be useful.
> 2) The name of F_NEXT is not fixed yet. another url of the austin says
> it is FD_NEXT.
>      So, we can't choose right name yet. Moreover, A meanings of 3rd
> argument of F_NEXT
>      haven't been fixed.
> 

But it still has the same braindamage: one system call per loop
invocation, and we can do better.  I would much rather see fdwalk() in SUS.

	-hpa