this post was submitted on 21 Oct 2024
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    [–] [email protected] 67 points 1 month ago* (last edited 1 month ago) (2 children)

    The query actually shows a lack of confidence. He should have googled "How to recover a file from /dev/null?" instead.

    [–] [email protected] 37 points 1 month ago (1 children)
    [–] [email protected] 1 points 1 month ago

    Can you not just try it with a dummy folder??

    [–] [email protected] 9 points 1 month ago* (last edited 1 month ago) (1 children)
    [–] [email protected] 8 points 1 month ago

    Top voted answer

    "Why would you want to?"

    [–] [email protected] 58 points 1 month ago (1 children)

    "... you don't. You recover it from /dev/random. Eventually."

    [–] [email protected] 12 points 1 month ago* (last edited 1 month ago)

    And if really want quality recovery, /dev/urandom. Might take a bit longer, but it's worth the wait 👌.

    [–] [email protected] 29 points 1 month ago (1 children)

    Duh, just read it back from /dev/random

    You will recover the data, you just need to wait long enough.

    [–] [email protected] 6 points 1 month ago

    Patience is key.

    [–] [email protected] 21 points 1 month ago (1 children)

    I mean, if the data was written to a HDD, then any forensic tool can read the magnetic residual patterns on the metal platters instead of looking for file headers?

    [–] [email protected] 17 points 1 month ago (1 children)

    That is true, though it would be pointless to look for it in /dev/null.

    [–] stoicmaverick 8 points 1 month ago (1 children)

    There is nothing in /dev/null, and no man needs nothing.

    [–] SmoothLiquidation 9 points 1 month ago (1 children)

    A hole would be something, this is NOTHING!

    [–] [email protected] 8 points 1 month ago

    /dev/void 🤔

    [–] stoicmaverick 18 points 1 month ago (1 children)

    That hack Torvalds keeps denying my pull request to implement /dev/aether which would immediately begin overwriting the entire disk and all other mounted storage with the repeating content of whatever is moved there.

    [–] [email protected] 8 points 1 month ago

    That is... brilliant! I love it!

    [–] [email protected] 15 points 1 month ago (3 children)

    Programmatically, what does the kernel actually do with data sent to /dev/null? Put it in a temp buffer and just delete it?

    [–] [email protected] 20 points 1 month ago (1 children)

    I was also curious, here's a good answer:

    https://unix.stackexchange.com/questions/670199/how-is-dev-null-implemented

    The implementation is:

    static ssize_t write_null(struct file *file, const char __user *buf,
                  size_t count, loff_t *ppos)
    {
        return count;
    }
    
    [–] [email protected] 16 points 1 month ago (1 children)

    So it's basically doing nothing and lying about it. 😆

    [–] [email protected] 17 points 1 month ago (1 children)

    "I accepted all of the bytes you gave me. I didn't do anything with them, but I accept you gave them to me".

    [–] [email protected] 4 points 1 month ago (1 children)

    Could've at least say thank you...

    [–] [email protected] 2 points 1 month ago (1 children)

    It's open source. If manners are an important feature to you perhaps look into contributing... :)

    [–] [email protected] 2 points 1 month ago

    Yeah, that could actually be fun to be honest, lol 😂. But I just know the PR would be rejected, lol 😂.

    [–] [email protected] 17 points 1 month ago

    The syscall to write passes a buffer and length. If it is Dev null the call just returns without doing anything more.

    [–] [email protected] 6 points 1 month ago* (last edited 1 month ago)

    Programmatically, what does the kernel actually do with data sent to /dev/null?

    I imagine it's like getting nullified in that olde show ReBoot.

    [–] [email protected] 2 points 1 month ago (1 children)

    Why would you be trying to recover something from a virtual device?

    [–] [email protected] 4 points 1 month ago* (last edited 1 month ago) (2 children)

    Because apparently, he moved it there... and doesn't know what /dev/null is...

    [–] [email protected] 2 points 1 month ago (1 children)

    It is still on the disk though

    Do people not understand how files work? Actually never mind that makes sense.

    [–] [email protected] 1 points 1 month ago
    [–] [email protected] 2 points 1 month ago (1 children)

    It is still on the disk though

    Do people not understand how files work? Actually never mind that makes sense.

    [–] shyguyblue 4 points 1 month ago

    Do people not understand how files work?

    Oh honey, imagine trying to tech-support a family of rednecks. Threaten to charge them for services and they'll stop pretty quick though...