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Re: [PLUG] Linux Bootable CD
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On Sat, 23 Mar 2002, Bill Jonas wrote:
> The fundamental difference between hard drives and CD-ROM drives is that
> hard drives *can have blank space*. CD-ROM discs don't.
>
> With a CD, there's no empty space on the disc. There are *unburned* (or
> unpressed) areas of the disc, but there's no blank space *in the
> filesystem*. This is the important difference.
>
> When you burn a CD, the disc gets "fixated". If you're reading the
> image off the disc (with your tool of choice), the kernel device driver
> returns EOF when it hits this point.
>
> Clearer?
>
> --
> Bill Jonas * bill@billjonas.com * http://www.billjonas.com/
>
But if you deleted or recopied a file on a CDR - the old file would
still be there and the new one would be written further out. So
technically there would be blank or junk space which would be copied with
the dd but of no value. If the file were large - say 100Megs, then the
image would contain 100 megs of junk. Just a point. I do understand now.
Thanks.
Doug
****************************
* Doug Crompton *
* Richboro, PA 18954 *
* 215-431-6307 *
* *
* doug@crompton.com *
* wa3dsp@wa3dsp.ampr.org *
* http://www.crompton.com *
****************************
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