empty waste basket securely

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iceburn
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Joined: 12/07/2019

With win 7 when certain items need deleting, they're put in the recycle bin and deleted using 'privazer'. I've looked in synaptic package manager but can find nothing similar here.

Is there a program to securely delete files with Trisquel ?

thanks.

calher

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Joined: 06/19/2015

If your hard drive is an SSD, there is no way to securely overwrite and
delete the file. The only solution is to take a sledge hammer to it.

If your hard drive is an old fashioned HDD, these 'secure delete'
programs should work.

iceburn
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Joined: 12/07/2019

Yes the HD is SSD.

rinakra
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Joined: 11/20/2019

wow really? What about this whole "writing everything over with zeros" business? That doesn't work for SSD's? There's no way. Then it would be like an infinite information well. Or do you just mean that you can't do it to individual files?

iceburn
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Joined: 12/07/2019

>wow really? What about this whole "writing everything over with zeros"
>business?
What about it ? Never had an SSD before so I'm at the ground floor.

That doesn't work for SSD's? There's no way. Then it would be like >an infinite information well. Or do you just mean that you can't do it to >individual files?

To be able to delete or overwrite individual files and or folders is what's wanted. After reading some articles about SSD it looks like the only way to destroy data is to take a sledge hammer to it.

liberpoolesque
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Joined: 01/07/2020

An SSD usually has more internal memory than advertised, so that wear leveling (you can read more on "wear leveling" on sites like Wikipedia) can be performed. This means that when you "overwrite" a specific address of the drive multiple times, the SSD may write over different internal memory blocks each time. This means that, if you "overwrite" the entire SSD, there may still be some of the old data left in those extra blocks, which can easily be recovered with some SSDs.
Even worse, if the SSD supports internal data compression, writing zeroes to the "entire" drive will only overwrite a tiny number of blocks.

If you want to get rid of an SSD, you should trigger its "secure erase" feature, because if the SSD uses automatic transparent encryption, this will make all data on it unreadable (by deleting the encryption key for the entire drive). Some low quality SSDs don't implement this correctly, they just pretend that it works.
There are some tutorials all over the internet that show how to do this using the "hdparm" command.

I suppose you could in addition use full-disk-encryption to protect your data, so that even if some of your data remains, it can't be read.

More on topic, securely deleting specific files is even trickier. If you ever copied the file around or edited it in any way, there may be multiple copies of it on the drive which can't be found anymore (even if it is a HDD).
Overwriting the file that the OS still knows of may not even overwrite the data on the drive (on an SSD, it almost definitely won't). Filling the entire remaining free space with random data afterwards may help on HDDs, except if the file was stored in an inode.

Magic Banana

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Joined: 07/24/2010

'shred' is a command-line program that is installed by default. See 'man shred'. 'wipe' is another one (not installed by default) that is integrated in Nautilus (install the package named "nautilus-wipe", from the package manager) that you may happen to use, as I do, although it is not Trisquel's default. There is 'secure-delete' too.