Phantom USB device!

[Peter King]

On Mon, Nov 03, 2003 at 12:12:36PM -0500, Ian Goldberg wrote:

> On Mon, Nov 03, 2003 at 12:05:28PM -0500, Peter King wrote:
> > But when I unplug the yepp, there the supposedly copied files aren't.
> > 
> > Curiously, I did succeed in deleting some files from the yepp. So Linux
> > knows it's there and can do at least *some* file manipulations. But not
> > write to it -- although Linux reports that the copy has been successful,
> > and duly notes the copied files in the yepp directory listing -- and it
> > even decrements the freespace left on the yepp appropriately.
> > 
> > What's wrong?
> 
> Are you doing a "umount" before pulling the USB cable out?  It's
> possible (likely?) Linux hasn't yet written the changes to the disk,
> but they're still in the cache.  I've seen similar behaviour when using
> a PCMCIA CF card reader.  The umount will flush the changes to the
> device, and then you can safely disconnect it.

Yes, I was unmounting it. It seems as though the USB-disk writes were
being deferred to that point, since nothing would happen immediately
after issuing a write command; on a umount there would be a noticeable
delay before the USB-disk was unmounted, and the LCD on the Yepp read
"Writing". It lied, apparently.

-- 
Peter King			        peter.king-H217xnMUJC0sA/PxXw9srA at public.gmane.org
Philosophy Department
University of Toronto			    (416)-978-3788 ofc
Toronto, ON   M5S 1A1			    (416)-978-8703 fax
    CANADA
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