From owner-freebsd-current  Tue Jul  2 16:40:15 2002
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Date: Tue, 2 Jul 2002 16:35:36 -0700 (PDT)
From: Julian Elischer <julian@elischer.org>
To: Garrett Wollman <wollman@lcs.mit.edu>
Cc: current@FreeBSD.ORG
Subject: Re: additional queue macro
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On Tue, 2 Jul 2002, Garrett Wollman wrote:

> <<On Tue, 2 Jul 2002 16:07:36 -0700 (PDT), Julian Elischer <julian@elischer.org> said:
> 
> > I would by the way argue that the statement "The queue macros always
> > guaranteed that traversal was safe in the presence of deletions" to be
> > false. Nowhere was this guaranteed, in fact the Manual page goes to
> > lengths to NOT do this..
> 
> I'm fairly certain that this *was* documented somewhere, at some point
> in time, although I can't find it in rev. 1.1 of either the
> documentation or the code.  Perhaps it was in a book (Stevens 2?).

I would add that there is no occurance I could find in the kernel that
assumes this.. (except the bad one I mentionned before in my own code) (at
least it all runs fine with -1 put in that location on deletion), so I
must not be alone in thinking that one shouldn't rely on it..


> 
> -GAWollman
> 
> 


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