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From: "Eugene L. Vorokov" <vel@bugz.infotecs.ru>
Message-Id: <200107061505.f66F56P01143@bugz.infotecs.ru>
Subject: Re: LIST_NEXT()
In-Reply-To: <200107061348.JAA26189@mail1.javanet.com> "from Evan Sarmiento at
 Jul 6, 2001 09:48:26 am"
To: Evan Sarmiento <kaworu@sektor7.ath.cx>
Date: Fri, 6 Jul 2001 19:05:06 +0400 (MSD)
Cc: freebsd-hackers@freebsd.org
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> Hello,
> 
> I'm writing a kernel module, and it involves traversing the proc list searching for the right structure,
> however, when I use SLIST_NEXT(p, p_list) in the program, I get a warning when I compile it: 
> 
> warning: statement with mo effect
> 
> What am I doing wrong? I've read the manpages on queue and looked at the proc structure.
> 
> Here's the code:
> int
> prfw_setflags(p, uap)
> struct proc *p;
> struct prfw_setflags_args *uap;
> {
> ...
> if (uap->id) {
>  while (uap->id != p->p_pid)
>   LIST_NEXT(p, p_list);
> }
> 
> ...
> }

The proper way would be:

    p = LIST_NEXT(p, p_list);

Regards,
Eugene


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