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I am using dcfldd to wipe a drive and lear forensics. I don't really want to have to deal with the math of the blocks and sectors, and just want dd or dcfldd to write over every possible bit on the drive or device.

As an example I saw this example on a site, too write ones to a drive

dcfldd pattern="11111111" of=/dev/hda bs=4096 conv=sync,notrunc

Why do you need 8 one's(I assume to make a byte) and what does notrunc mean, as well as the sync option. Also with the bs= option, is bigger always better and faster?

I have read the man page but don't understand the keywords.

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up vote 1 down vote accepted

According to the dcfldd man page:

sync: pad every input block with NULs to ibs-size; when used with block or unblock, pad with spaces rather than NULs

notrunc: do not truncate the output file

Basically, the man page should be able to answer all your questions.

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Yeah I read the manpage, but have no idea what it means. That's why I was asking. – Recursion Dec 8 '09 at 22:25

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