how to extract 512 bytes from a file

[Sergey Zaharchenko]

On Fri, Jun 18, 2004 at 11:36:04PM -0400,
 Thomas Farrell probably wrote:

> I was thinking I could take a working avi and extract the first 512
> bytes and insert it into the beginning of a bogus file. Does anyone
> think this may work?

Given the number of compression formats actually hiding under the '.avi'
extension, and that the most sensitive information is usually in the
header, I doubt that. Unless you know for sure what should be there,
this won't work.

> Any idea how I can accomplish this?

dd(1). Especially `seek=...', `skip=...' and `conv=notrunc'.

> Do I smoke too much weed?

Only if you think you're going to guess 512 bytes of the header from
scratch:)

-- 
DoubleF
Any excuse will serve a tyrant.
		-- Aesop
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