in reply to Cleaning up your hard disk

On Unix, you'd do it in half a line: 
    dd if=/dev/random of=/some/path

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You may replace /dev/random with /dev/urandom if you like, and you can wipe an entire disk or partition by giving the device file as argument to of.

Abigail

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Re: Cleaning up your hard disk
by b10m (Vicar) on Jan 26, 2004 at 15:39 UTC

    ... or just use something like wipe

    --
    b10m
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      They tell me there is something like this within PGP, even if I have never tried it.
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        I personally use PGP Wipe for situations like this. If we're going to talk about sufficently motivated people, any hack you write or tool you use should wipe multiple times. Once is not enough to ensure data unrecoverability, try 3 passes; or upwards of 9 passes if you're really paranoid...

        - jbWare
        Just because you're paranoid, doesn't mean they're not out to get you.
[reply]
Re: Re: Cleaning up your hard disk
by l3nz (Friar) on Jan 26, 2004 at 12:54 UTC
    Of course you could also 
    open F, ">file.txt";
while() { print F chr rand( 20 ) + 65; }

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    And break it when it's done.
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[d/l]

      No, not a good idea.

      This will use all the bit patterns between 100_0001 and 101_0101. Of interest is that the upper 3 bit are always set to 010. This flaw might be sufficient to allow a sufficiently motivated person to extract something useful.

      This would be better written as

          1 while print F chr(rand(256));

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      As an added bonus, when the file system is full, the print wil fail, the call will return 0 and bingo! you fall out of the while. At least I believe that that is what should happen. You'll forgive me if I don't try this out on my own filesystem...

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[d/l]

In Section Cool Uses for Perl