devfs and hot unplugging firewire device

[M. L. Dodson]

On Wednesday 20 September 2006 23:03, John-Mark Gurney wrote:
> Eric Anderson wrote this message on Wed, Sep 20, 2006 at 21:57 -0500:
> > On 09/20/06 15:16, M. L. Dodson wrote:
> > >On Wednesday 20 September 2006 14:42, John-Mark Gurney wrote:
> > >>M. L. Dodson wrote this message on Wed, Sep 20, 2006 at 14:14 -0500:
> > >>>More experimental results on firewire disks and hot unplugging:
> > >>>
> > >>>Transcripts of two sessions can be retrieved from
> > >>>http://siegfried.utmb.edu/bdodson/firewire.on.histidine.txt and
> > >>>http://siegfried.utmb.edu/bdodson/firewire.on.serine.txt
> > >>
> > >>doh, I think I know what your problem is...  you need to do three
> > >>or so fwcontrol -r's before the device will disappear...  This is
> > >>necessary, since each plug causes a rescan, and you don't want
> > >> devices disappearing when you add your cd drive...  It looks like
> > >> adding a timeout would be a good thing to the device orphan...  If
> > >> the device has been orphaned for more than a minute, drop it, or
> > >> three or so resets...
> > >
> > >That worked.  Thanks again!
> >
> > It's too bad firewire doesn't act more like USB storage in this case -
> > you can yank and plug in the same or similar storage using the same
> > adapter many many times without issue - I've done this many times.
>

And that is the behaviour I expected.  I did not appreciate the
differences between a chain and a tree.  I'm a scientist, but not
a computer scientist.  I have been somewhat verbose in these
emails to document my experiences for the archives.  Thanks to you
all.

> USB is a tree w/ hubs... If you have a chain of devices, and need to
> pull one in the middle, you'd loose the end devices if firewire
> behaved this way...
>
> /me notes that each have their advantages and disadvantages.

-- 
M. L. Dodson
Email:	mldodson-at-houston-dot-rr-dot-com
Phone:	eight_three_two-56_three-386_one