ubuntu: destroy a huge binary file and make it non-readable.

[Nandakumar]

This package may help you:
https://launchpad.net/gopanam/+download

You encrypt the file with a key, and if the key is unknown, even the
developer can't decrypt it.

On 1/26/14, John R. Sowden <jsowden at americansentry.net> wrote:
> On 01/26/2014 01:51 AM, Johnny Rosenberg wrote:
>> 2014-01-25 ping song <songpingemail at gmail.com
>> <mailto:songpingemail at gmail.com>>
>>
>>     thanks.
>>     but guess I haven't make it clear.
>>
>>     my goal is to :
>>     1) not to delete the file, not to chmod either
>>     2) don't change the file size either
>>     3) make the gzip file not being able to ungzipped and viewed -
>>     just to mess up the file and make it not usable (what I meant
>>     "destroy").
>>
>>     I finally use GNU "head" to delete the last a couple of lines like
>>     this:
>>
>>     head --lines=-100 myfile.gz > newfile.gz
>>
>>     after this , gzip can't recogize it. that's it.
>>
>>     but , I doubt this is not the safe way, coz an gzip expert might
>>     be easily open the binary file and fixed the missed lines (I'm not
>>     sure).
>>
>>     maybe I better 'sort' the whole file, or, swap randomly some
>>     lines, so there is no way the file can be read...
>>
>>
>>
>> I know this is way off topic, but I'm just curious: Why do you want to
>> do this? Is the file ever going to be readable again? If not, why not
>> just delete it...? If you want to be able to open the file yourself
>> but nobody else, why not just protect it (encrypt it) with a password?
>>
>> Johnny Rosenberg
>>
>>
>>
>>
>>     On Sat, Jan 25, 2014 at 12:09 PM, Liam Proven <lproven at gmail.com
>>     <mailto:lproven at gmail.com>> wrote:
>>
>>         On 25 January 2014 16:17, ping song <songpingemail at gmail.com
>>         <mailto:songpingemail at gmail.com>> wrote:
>>         > may sounds like a sin, but I just wanna know the best way to
>>         change a binary
>>         > file without actually open it (since it's really huge)?
>>
>>         Your subject says "destroy". To me that would seem to mean
>>         securely erase.
>>
>>         But your body text seems to ask about editing it.
>>
>>         As such, I do not understand what you mean.
>>
>>         If you do mean secure erase, read this:
>>
>>
>> http://askubuntu.com/questions/57572/how-to-delete-files-in-secure-manner
>>
>>
>>         --
>>         Liam Proven . Profile: http://lproven.livejournal.com/profile
>>         Email: lproven at cix.co.uk <mailto:lproven at cix.co.uk> .
>>         GMail/G+/Twitter/Flickr/Facebook: lproven
>>         MSN: lproven at hotmail.com <mailto:lproven at hotmail.com> .
>>         Skype/AIM/Yahoo/LinkedIn: liamproven
>>         Tel: +44 20-8685-0498 <tel:%2B44%2020-8685-0498> . Cell: +44
>>         7939-087884 <tel:%2B44%207939-087884>
>>
>>
> we're all sitting on the edge of our chairs waiting for this answer :)
>
>