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Re: cdrtools-2.01a37 ready



> Are there objections against having the only track of a CD
> ending with 300+ kB of _ non-zero _ pad bytes rather than the
> padding provided by  cdrecord padsize=...  or  mkisofs -pad  ?
> 
> A short "is ok" or "better pad 300 kB zeros" would be of help.

If this 300kb (150 sectors, 2 seconds) is to separate the tracks from
each other, the spec is that it must be silent, i.e. zeros.

If the padding is purely to work around the kernel bug which reads more
blocks than will ever be used, the actual data content is irrelevant.

If you want to store data (e.g. checksums) past the end of the
filesystem, write the filesystem first, then your data (any size,
obviously within limits of recording capacity), then 150 blocks of
zeros. From the drive's point of view, it's only interested in the
zeros. From the filesystem's point of view, it's not interested in any
block beyond the last one belonging to the filesystem. With dd, you can
easily access anything but may run into trouble for accessing the last
150 blocks; with Linux you will run into trouble before then.

You could consolidate all requirements by writing:

* filesystem blocks
* your additional data blocks
* sufficient number of rubbish blocks to keep the kernel happy (150
  minimum), I'd use 500 esp on a dvd, there's no reason not to use zeros
* 150 blocks of zeros

Volker

-- 
Volker Kuhlmann			is possibly list0570 with the domain in header
http://volker.dnsalias.net/		Please do not CC list postings to me.



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