Re: [PATCH v2] Add preadv and pwritev system calls.

[Scott Lurndal <scott.lurndal@3leafsystems.com>]

On Fri, Dec 12, 2008 at 05:02:05PM +0100, Gerd Hoffmann wrote:
> Matthew Wilcox wrote:
> > On the other hand, NetBSD have approximately 0% market share.
> > We shouldn't let them lock us into making a bad decision.  Is there
> > anyone other than NetBSD who has added these syscalls?
> 
> Free- and OpenBSD have it too.  For Solaris I've found a feature request
> only.  Dunno about MacOS/Darwin.  Other un*xes which are important these
> days?
> 
> I'd *really* hate it to have the same system call with different
> argument ordering on different systems though.  Especially when swapping
> two integer values, so gcc wouldn't error out on wrong usage.

I would suggest that from the end-users perspective, the user-mode API
should be similar to pread/pwrite, e.g:

    int preadv(fd, iovec, iovec_size, offset)

scott