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Date: Fri, 12 Dec 2008 21:02:31 +0100
From: Gerd Hoffmann <kraxel@redhat.com>
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To: Arnd Bergmann <arnd@arndb.de>
CC: Matthew Wilcox <matthew@wil.cx>, linux-kernel@vger.kernel.org,
       linux-arch@vger.kernel.org
Subject: Re: [PATCH v2] Add preadv and pwritev system calls.
References: <1229090440-32120-1-git-send-email-kraxel@redhat.com> <20081212152929.GM26095@parisc-linux.org> <200812122047.31405.arnd@arndb.de>
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Arnd Bergmann wrote:
> Aside from that, have you considered doing something even more flexible,
> like this?
> 
> struct piovec {
> 	void __user *iov_base;
> 	__kernel_size_t	iov_len;
> 	__kernel_loff_t pos;
> };
> 
> asmlinkage ssize_t sys_pwritev(unsigned long fd,
>                                const struct piovec __user *vec,
>                                unsigned long vlen);

There is little point in doing so because I *really* want the
user-visible API being identical to the existing ones in the *BSD
family.  Anything else is just a PITA for the applications using this.

cheers,
  Gerd