Roland Smith <> wrote:
> On Thu, Apr 09, 2009 at 12:47:23PM -0700, wrote:
> > It's an SD card, not a "drive", so I had not expected it to be
> > partitioned; but yes, it is:
> > 
> > $ ls -l /dev/da0*
> > crw-r-----  1 root  operator    0, 244 Feb 14 15:09 /dev/da0
> > crw-r-----  1 root  operator    0, 245 Feb 14 15:09 /dev/da0s1
> That would suggest that there is a filesystem on there, doesn't it?

It would certainly suggest there is a DOS "partition" table aka
BSD "slice" table.  I don't think it says anything about what the
slice contains, however.

> > $ dd if=/dev/da0 of=~/sd bs=1b
> > 
> > That's been running for something like 45 minutes now, and based
> > on the size of the output file it has read about a tenth of the
> > card.
> Reading one byte at a time is bound to be slow.

"dd bs=1b" is one block (512 bytes), not one byte.

At least it seems to be working.  I *would* anticipate problems if
trying to read a umass device in units not a multiple of its native

> It could be that this USB chipset needs some "quirks" to work
> correctly.

like "Don't attempt to read more than 32768 bytes at a time" --
subsequent testing shows it to be OK up to bs=64b, but bs=126b
fails -- or is there maybe a way to set that sort of limit in
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