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    SubjectRe: Problems accessing USB Mass Storage
    The device may not actually have the beginning few sectors.  Use skip= to
    try to read something from the middle of the media.

    Yes, I actually have seen this before. The firmware 'fakes' a partition
    table on the first attempt to read one, but sector 0 really isn't there.

    Matt

    On Tue, Sep 17, 2002 at 02:50:32PM -0500, Thomas Dodd wrote:
    >
    > Mark C. Wrote:
    > >>> [root@stimpy dev]# dd if=/dev/sda of=/dev/null bs=1k count=1
    > >>> dd: reading `/dev/sda': Input/output error
    > >>> 0+0 records in
    > >>> 0+0 records out
    >
    >
    > Randy.Dunlap wrote:
    > > On Tue, 17 Sep 2002, Jonathan Corbet wrote:
    > >
    > > |
    > > | You might try just using dd to copy your card to disk with an offset of 25
    > > | sectors, and see of you can mount the resulting image.
    > >
    > > This is a bit like what we (JE, David Brownell, and I) saw at
    > > the USB plugfest in 1999. We had a camera device that we
    > > couldn't mount as a filesystem, but we could dd it.
    > > When we did that and studied the dd-ed file, we could see a
    > > FAT filesystem beginning after the first <N> blocks (but more than
    > > 25 sectors IIRC -- more like after 50-100 KB, or maybe even more).
    >
    > See the above form Mark's post. He tried to dd a 1K block
    > and it failed. Granted, The first few blocks may need to be skipped,
    > but right now he cannot even get the raw data out.
    >
    > If we can get the data, we can use the loop device to mount it.
    >
    > Any ideas to figure out the why the dd fails?
    >
    > -Thomas
    >
    >
    > -
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    --
    Matthew Dharm Home: mdharm-usb@one-eyed-alien.net
    Maintainer, Linux USB Mass Storage Driver

    How would you like this tie wrapped around your hairy round head?
    -- Greg
    User Friendly, 9/2/1998
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