Subject: Re: sysctl function and ROUNDUP kernel bug
To: David Waitzman <>
From: None <Chris_G_Demetriou@NIAGARA.NECTAR.CS.CMU.EDU>
List: current-users
Date: 01/30/1996 17:00:12
David Waitzman <> asked on port-alpha (referring to
the sysctl variable described by [CTL_NET, PF_ROUTE, 0, 0,
> I also note that the man pages are less than helpful.  sysctl(3) says
> to look at route(4) for information on the above variable.  route(4)
> doesn't mention the variable.  It does mention the getkerninfo(2)
> system call which doesn't exist anymore.  sysctl(3) should also
> mention the undocumented system call __sysctl(2).

It sounds like the fact that route(4) doesn't provide you with the
info you need, and that sysctl(3) refers you to it to find that
information, is a bug.  I'd suggest submitting a PR about it.

re: __sysctl(2) being undocumented: I don't think it's unreasonable to
say that users will _never_ call __sysctl(), and given that, i can't
think of a good reason to let them know that it exists at all.
__sysctl() is an artifact of the implementation of sysctl(3), and
should never, ever be invoked by the user...  thoughts?