Date: Sat, 15 May 1999 10:16:51 +0200 (SAST) From: Robert Nordier <rnordier@nordier.com> To: jdp@polstra.com (John Polstra) Cc: mike@smith.net.au, stable@freebsd.org Subject: Re: equivalent to "-P" in boot.config Message-ID: <199905150816.KAA22268@ceia.nordier.com> In-Reply-To: <199905150137.SAA03336@vashon.polstra.com> from John Polstra at "May 14, 1999 06:37:40 pm"
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John Polstra wrote:
> In article <199905142221.PAA02318@dingo.cdrom.com>,
> Mike Smith <mike@smith.net.au> wrote:
> > > What's the new /boot/loader.rc equivalent of -P in /boot.config?
> >
> > -P in /boot.config (This is the best place to do it)
>
> I'm curious about how it fits together. Does the bootblock code pass
> the -P to /boot/loader, which then does the right thing with it?
The -P is completely handled by boot2. The effect is to set the
bootblock -D (dual) and -h (serial) options, if no keyboard is found.
When control is passed to /boot/loader (and, because loader
masquerades as an a.out kernel, the bootblocks are never completely
sure whether they are loading loader or loading a kernel) the -h
option causes a bit to be set in the "howto" flags passed to the
kernel.
So, the only outward result of -P is that
(howto & RB_SERIAL)
is non-zero, and this is what loader (or the kernel) reacts to.
It's useful to have the -P or -h options in /boot.config in case
control never reaches loader: both to see diagnostics and because,
if /boot/loader is inaccessible, the bootblocks will attempt to
boot the kernel directly.
--
Robert Nordier
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