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Date: Sat, 6 Aug 2005 09:04:23 +0200
From: Jeremie Le Hen <jeremie@le-hen.org>
To: "Thordur I. Bjornsson" <thib@mi.is>
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Cc: freebsd-hackers@freebsd.org
Subject: Re: Checking sysctl values from within the kernel.
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Hi Thordur,

> PS: If you don't mind, what is a "real accessor function" ?

This is a function acting as a wrapper for accessing an integer
declared as static.  This function must of course live in the same
file.  This may be something like this, there may exist neater
interfaces though :


static int age;

int
age_accessor(int *get, int set)
{

	if (get != NULL)
		*get = age;
	else if (set < 0 || set > 125)
		return -1;
	else
		age = set;
	return 0;
}


If `get' is not NULL, this means the caller wants to retrieve the
current age value.  Else, this means the caller wants to set the age
value to a new one : if the latter is lower than 0 and greater than
125, this is an incredible age and the accessor reports an error.
Else it sets the new value.

I hope this helped.

Regards,
-- 
Jeremie Le Hen
< jeremie at le-hen dot org >< ttz at chchile dot org >