Skip site navigation (1)Skip section navigation (2)
Date:      Sat, 11 Dec 1999 02:50:03 -0800
From:      "Jordan K. Hubbard" <jkh@zippy.cdrom.com>
To:        Archie Cobbs <archie@whistle.com>
Cc:        abial@webgiro.com (Andrzej Bialecki), freebsd-current@FreeBSD.ORG
Subject:   Re: Modules and sysctl tree 
Message-ID:  <81199.944909403@zippy.cdrom.com>
In-Reply-To: Your message of "Thu, 09 Dec 1999 15:59:35 PST." <199912092359.PAA76217@bubba.whistle.com> 

next in thread | previous in thread | raw e-mail | index | archive | help
> I think the latter. In 'theory' there should be no discernable
> difference between functionality from a KLD vs. the same functionality
> compiled directly into the kernel.

Only in theory, of course. :)

As Andrzej has already pointed out, modules can also be loaded and
unloaded, creating a sysctl space where things enter and leave
dynamically.  Let's say I'm somebody who creates a nifty little GUI
sysctl editor for the CLI-challenged and, because it's time-consuming
to build a form with fields for all the relevant sysctl variables, I
take the obvious shortcut of parsing the output of `sysctl -A' once at
startup time and then dealing with the individual field callbacks
thereafter.  On my "classic" system with a config-generated kernel,
this works just fine and my GUI front-end for sysctl is eventually
declared "useful enough" that I start handing it around.  Then
somebody who actually loads and unloads klds tries to use it, and
results (needless to say) are no longer quite in alignment with
expectations. :)  Just a hypothetical scenario, of course, but
I simply wanted to make the point that "no discernable difference"
might be hard to achieve for certain values of discernment.

- Jordan


To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-current" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?81199.944909403>