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Date: Thu, 9 May 1996 12:07:56 +1000
From: Bruce Evans <bde@zeta.org.au>
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To: babbleon@mercury.interpath.com, freebsd-hackers@FreeBSD.ORG,
        freebsd-hardware@FreeBSD.ORG
Subject: Re: Uknown CD-ROM : debugging a driver
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>I started out by putting a few printf statements about, but that gets
>sorta of tedious as I have to reboot each time I rebuild, so I got the
>...

>QUESTIONS:
>  - I'm surely not the first to do this sort of thing.  How does one
>    usually do it?

I usually use ddb, and sometimes add code to log events, and sometimes
load small test lkms.

>  - Where is doc on ddb, if that's the best way to look at this?
>  - For that matter, where is ddb itself?
>    I have a man page, but no command, and I did a string search in

See another reply.

>  - I want to watch the probing along with the open &c.
>    How can I get FreeBSD to probe for a device *after* the system
>    has booted and the rest of it is sane rather than before?

This isn't supported for most devices.  However, parts of the wcd driver
are in an lkm which can be loaded at any time, and you can always write
a tiny lkm to call the probe routine, or call the probe routine in ddb.

Bruce