How to compute sha256sum

[Mr. Teo En Ming (Zhang Enming)]

On Thu, Nov 19, 2009 at 1:11 PM, Reg Clemens <reg at dwf.com> wrote:

> This may seem to be a stupid question, but .
>
> I can download a iso image of Fedora, then do a sha256sum of the file
> and I get the result shown in the SHASUM file.
>
> I can burn a DVD with k3b, ask for it to verify the checksum, and
> have it say the checksum is OK.
>
> But if I just do
>        sha256sum /dev/cdrom
>
> I get a result which is NOT the published sum, even tho k3b said the
> sum was going to be OK.
>
> So what am I doing wrong?  (and yes cdrom and dvd both point to sr0)
>
> --
>                                        Reg.Clemens
>                                        reg at dwf.com
>
>
> --
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Try

dd if=/dev/cdrom of=/home/reg/DVD-image.iso

Then

sha256sum /home/reg/DVD-image.iso

-- 
Mr. Teo En Ming (Zhang Enming) Dip(Mechatronics) BEng(Hons)(Mechanical
Engineering)
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