From owner-freebsd-hackers@FreeBSD.ORG  Sat Aug 21 20:29:44 2004
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To: Alfred Perlstein <alfred@freebsd.org>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Sat, 21 Aug 2004 13:02:05 PDT."
             <20040821200205.GE26612@elvis.mu.org> 
Date: Sat, 21 Aug 2004 22:29:41 +0200
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cc: hackers@freebsd.org
Subject: Re: sysctl hacks 
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In message <20040821200205.GE26612@elvis.mu.org>, Alfred Perlstein writes:
>I'm doing some work that requires that I have a sysctl structure
>be passed around, but inside that structure are several pointers I
>may need to dereference.
>
>Basically:
>
>struct mysysctldata {
>   .... (data here)
>   void *moredata;
>   size_t morelen;
>};
>
>What is the proper way of sysctl'ing IN the data from moredata?
>
>I need to make a copy of the sysctl req, but... I'm not sure what
>to initialize the 'lock' member to.

Just use the SYSCTL_IN() and ..._OUT() functions.

-- 
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.