Subject: Re: New read & write syscalls
To: None <tech-kern@netbsd.org>
From: Ignatios Souvatzis <is@jocelyn.rhein.de>
List: tech-kern
Date: 06/30/1999 21:16:53
On Wed, Jun 30, 1999 at 11:40:30AM -0700, Chris G. Demetriou wrote:
> non-iovec is the common case, _and_ creating the iovec in user-land is
> going to make for a slower syscall (have to copy it in, rather than
> just get the information from the syscall args, do more error checking
> because of the possible iovec cases, etc.).
> 
> So why penalize the common case?

ok... actually, for modern register-passing-ABI cpus, I see that read/write
is faster... I was only thinking of stack ABI cpus, which might even be
able to have a zero-copy (hm, actually: one-copy) assembler stub.

> In any case before a flameware erupts, re: the existing readv/writev
> vs. read/write: IT AIN'T BROKE, SO DON'T PROPOSE TO FIX IT!!!  8-)

okokok.
	-is