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Date: Tue, 26 Jan 2016 18:25:43 +0100
From: Gary Jennejohn <gljennjohn@gmail.com>
To: Luigi Rizzo <rizzo@iet.unipi.it>
Cc: Konstantin Belousov <kostikbel@gmail.com>, Boris Astardzhiev
<boris.astardzhiev@gmail.com>, threads@freebsd.org,
"freebsd-net@freebsd.org" <net@freebsd.org>
Subject: Re: Does FreeBSD have sendmmsg or recvmmsg system calls?
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On Tue, 26 Jan 2016 09:06:39 -0800
Luigi Rizzo <rizzo@iet.unipi.it> wrote:
> On Tue, Jan 26, 2016 at 5:40 AM, Konstantin Belousov
> <kostikbel@gmail.com> wrote:
> > On Mon, Jan 25, 2016 at 11:22:13AM +0200, Boris Astardzhiev wrote:
> >> +ssize_t
> >> +recvmmsg(int s, struct mmsghdr *__restrict msgvec, size_t vlen, int flags,
> >> + const struct timespec *__restrict timeout)
> >> +{
> >> + size_t i, rcvd;
> >> + ssize_t ret;
> >> +
> >> + if (timeout != NULL) {
> >> + fd_set fds;
> >> + int res;
> > Please move all local definitions to the beginning of the function.
>
> This style recommendation was from 30 years ago and is
> bad programming practice, as it tends to complicate analysis
> for the human and increase the chance of improper usage of
> variables.
>
> We should move away from this for new code.
>
Really? I personally find having all variables grouped together
much easier to understand. Stumbling across declarations in the
middle of the code in a for-loop, for example, takes me by surprise.
I also greatly dislike initializing variables in their declarations.
Maybe I'm just old fashioned since I have been writing C-code for
more than 30 years.
--
Gary Jennejohn