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Date: Thu, 3 Jan 2002 00:46:45 -0800 (PST)
From: Julian Elischer <julian@elischer.org>
To: Poul-Henning Kamp <phk@critter.freebsd.dk>
Cc: Stephen McKay <mckay@thehub.com.au>,
	John Baldwin <jhb@FreeBSD.org>, cvs-all@FreeBSD.org,
	cvs-committers@FreeBSD.org, Julian Elischer <julian@FreeBSD.org>,
	Greg Lehey <grog@FreeBSD.org>
Subject: Re: cvs commit: src/share/man/man3 queue.3 
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On Wed, 2 Jan 2002, Poul-Henning Kamp wrote:

> In message <Pine.BSF.4.21.0201020933320.19204-100000@InterJet.elischer.org>, Ju
> lian Elischer writes:
> 
> >how about explicitly detailing that it's NULL at the end?
> >Doesn't that also work?
> 
> I don't think we should document that.
> 
> There are types of lists/queues which doesn't naturally end with
> that condition.  That is why we have the FOO_EMPTY() clause, although
> people tend to also rely on
> 
> 	if (FOO_FIRST(...) == NULL)
> 		/* nothing to do */

Since TAILQ_FIRST== NULL is a termination (it's empty) 
condition (as is TAILQ_NEXT() == NULL)
it makes PERFECT sense that a completed set of iterations ends up
with the pointer being NULL.

Sometimes I reckon you are bloody minded just for the sheer fun of it..



> 
> -- 
> Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
> phk@FreeBSD.ORG         | TCP/IP since RFC 956
> FreeBSD committer       | BSD since 4.3-tahoe    
> Never attribute to malice what can adequately be explained by incompetence.
> 


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