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Anyone know about interaction of 'dd' with memory cards?
- From: "Dave Korn" <dave dot korn at artimi dot com>
- To: <cygwin at cygwin dot com>
- Date: Thu, 22 Sep 2005 18:22:24 +0100
- Subject: Anyone know about interaction of 'dd' with memory cards?
Hi all,
I've got a PC here with a memory card reader. I've been using 'dd' like
so:
dd if=/dev/sdb bs=1024 count=32768 of=cf.img
to make image files from the contents of the disk. What didn't work, OTOH,
was this:
dd if=/dev/sdb bs=1024 of=cf.img
I was hoping that when I left the count argument out, dd would just read
the entire disk volume and stop when it reached the end. But it didn't: the
file grew to several Gb before I Ctrl-C'd it.
Now, dd is supposed to terminate the copy operation when it reaches EOF on
the input, and I doubt that is broken. What I'm wondering is, I _expected_
that reading /dev/sdb would give an EOF when the entire drive's contents had
been read. Was this a false assumption? Is Cygwin _supposed_ to return an
EOF when you reach the end of a device volume, and it (or dd) is broken, or
has this never been implemented?
cheers,
DaveK
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Can't think of a witty .sigline today....
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