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Date: Wed, 01 May 2013 13:57:51 +1000
From: Lawrence Stewart <lstewart@freebsd.org>
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Subject: Adding a FOREACH_CONTINUE() variant to queue(3)
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[reposting from freebsd-arch@ - was probably the wrong list]

Hi all,

I've had use for these a few times now when wanting to restart a loop at
a previously found element, and wonder if there are any thoughts about
sticking them (and equivalents for other list types) in <sys/queue.h>?

Cheers,
Lawrence

#define TAILQ_FOREACH_CONTINUE(var, head, field)		\
	for ((var) = ((var) ? (var) : TAILQ_FIRST((head)));	\
	(var);							\
	(var) = TAILQ_NEXT((var), field))


#define SLIST_FOREACH_CONTINUE(var, head, field)		\
	for ((var) = ((var) ? (var) : SLIST_FIRST((head)));	\
	(var);							\
	(var) = SLIST_NEXT((var), field))