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To: arch@freebsd.org
Subject: sockaddr API question
From: Poul-Henning Kamp <phk@phk.freebsd.dk>
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Date: Mon, 05 Aug 2013 07:05:07 +0000
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The theoretical variant of the question:
	Where the length of a sockaddr must be passed to an API,
	library or kernel, is it _always_ legal for the length to
	be larger than the relevant subtype of struct sockaddr ?

The practical variant of the question:
	Can I just use struct sockaddr_storage all over the place
	and give sizeof(struct sockaddr_storage) to sockaddr_len arguments ?

PS: Yes, I realize that there will be inefficiencies related to
moving more data than required, the question is only if it is safe,
not if it is a good idea.

-- 
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.