Subject: Re: CVS commit: src/sys/uvm
To: Christos Zoulas <christos@astron.com>
From: Antti Kantee <pooka@cs.hut.fi>
List: source-changes
Date: 05/12/2007 00:38:50
On Fri May 11 2007 at 21:02:04 +0000, Christos Zoulas wrote:
> >On a related note, SUS says that len==0 should return EINVAL, not succeed
> >with no action like our code does. Is this emulating some prehistoric
> >behaviour?
>
> For some calls 0 is an error, for others it is ok. I don't know the
> rationale behind it. I'd say let's leave it alone for now.
Well, it's the null problem, both approaches are correct. But I was
actually bitten by this just this week. I thought my mapping succeeded
and was looking for the error in the completely wrong place. In reality
my mapping had only "succeeded" because of len 0, where len 0 was due
to the actual bug.
But that's not to say something historic might not rely on len==0 =>
success.
--
Antti Kantee <pooka@iki.fi> Of course he runs NetBSD
http://www.iki.fi/pooka/ http://www.NetBSD.org/
"la qualité la plus indispensable du cuisinier est l'exactitude"