Re: filemon

From: Dag-Erling_Smørgrav <des_at_FreeBSD.org>
Date: Tue, 30 Jul 2024 11:44:18 UTC
"Poul-Henning Kamp" <phk@phk.freebsd.dk> writes:
> Dag-Erling Smørgrav <des@FreeBSD.org> writes:
> > There is very little difference between options and devices in kernel
> > configuration files, but for what it's worth, filemon is a device, not
> > an option.
> Apart from the internals of config(8) and it's input data, is there
> any actual difference left ?

From the perspective of including files in the build, there is no
difference: `foo/foo.c optional foo` does not care whether "foo" is an
option or a device.  However, options generate macros, while devices
don't.  So adding `option FILEMON` to your kernel config will cause
filemon to be compiled into the kernel, but it will also generate an
unneeded opt_filemon.h with `#define FILEMON 1`.  Or it would, if it
weren't for this:

    % git annotate sys/conf/options |& grep -i filemon
    6c6f1f0185b84	(Peter Wemm	2013-07-03 20:22:12 +0000	109)FILEMON	opt_dontuse.h

which suggests Peter intended filemon to be an option rather than a
device.

DES
-- 
Dag-Erling Smørgrav - des@FreeBSD.org