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Date:   Sat, 25 May 2019 00:45:49 +0100
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Alexey Dobriyan <adobriyan@gmail.com>
Cc:     Linus Torvalds <torvalds@linux-foundation.org>,
        Christian Brauner <christian@brauner.io>,
        Linux List Kernel Mailing <linux-kernel@vger.kernel.org>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>
Subject: Re: [PATCH v2 0/2] close_range()
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On Sat, May 25, 2019 at 12:27:40AM +0300, Alexey Dobriyan wrote:

> What about orthogonality of interfaces?
> 
> 	fdmap()
> 	bulk_close()
> 
> Now fdmap() can be reused for lsof/criu and it is only 2 system calls
> for close-everything usecase which is OK because readdir is 4(!) minimum:
> 
> 	open
> 	getdents
> 	getdents() = 0
> 	close
> 
> Writing all of this I understood how fdmap can be made more faster which
> neither getdents() nor even read() have the luxury of: it can return
> a flag if more data is available so that application would do next fdmap()
> only if truly necessary.

Tactless question: what has traumatised you so badly about string operations?
Because that seems to be the common denominator to a lot of things...