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From: Wojciech Puchar <wojtek@wojtek.tensor.gdynia.pl>
To: Tim Judd <tajudd@gmail.com>
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Cc: Gary Kline <kline@thought.org>, Polytropon <freebsd@edvax.de>,
	FreeBSD Mailing List <freebsd-questions@freebsd.org>
Subject: Re: How-to erase a DVD-RW
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>> which is exactly what i suggested - writing 0 byte disc
>
>
> that writes binary 0, the ASCII "NUL" character.  /dev/zero is NOT a 
> zero-size file.

yes it is

[wojtek@wojtek ~/NOBACKUP]$ dd if=/dev/null of=/dev/null bs=1
0+0 records in
0+0 records out
0 bytes transferred in 0.000037 secs (0 bytes/sec)


/dev/null simply gives EOF when trying to read