> And I want to rip out just "a" to write to another disk.  First, its
> imperative to have the fdisk setup correctly, though for a flash device,
> creating a whole partition on 3 works well, (fdisk -e sd0, e 3, A6,
> follow prompts).
> 
> Once you've got your partition created, remember to dd out the first 63
> sectors along with the size of the partition.  So you'd do "dd
> if=/dev/wd0 bs=512 of=wd0a.img count=819504" and write it out with "dd
> if=wd0a.img of=/dev/sd0c".
> 
...
> To copy out the "d" partition for example, its as simple as doing "dd
> if=/dev/wd0 of=wd0d.img bs=512 skip=1639008". The "skip" flag size is
> calculated by looking at the size of a+b+63 (63 being the initial offset
> of "a").
> 
> Hope this helps clear up some things.  Also, "bs=512" isn't needed, I
> just use it in my scripts to tell other people who may use it later that
> the default blocksize is 512 in case they're not clued up enough to know
> this.

Wow, thanks for the detailed break down, that is great.

Just a quick follow up, are you saying that I should not increase the bs size, 
ie from bs=512 (the default if nothing is specified) to bs=20m?  I ask this b/c 
using a bs=20m speeds up the writing to my usb-cf reader significantly (like 10 
minutes rather then 4 hours).

Thanks again,
Gordo.

--
http://www.gordonturner.ca

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