5 ms·

LOL this was a common thing in high school for me but one teacher was more technically literate than we gave him credit for and in class (with overhead projecto

by qq66 5y ago

LOL this was a common thing in high school for me but one teacher was more technically literate than we gave him credit for and in class (with overhead projectors LOL) called the student out in front of the whole class and had printouts of the hex where he had fucked with it and gave him a 0. I don't think you could drag a kid publicly that way today, some parent would get the administration up your ass.

Handytinge 5y ago
What could parent complain about? I'm lost.
ARandomerDude 5y ago
That man believed in teaching more than what was in the textbook. Kudos for the lesson in integrity.
suifbwish 5y ago
There are ways to corrupt a file without messing with the hex content of the file
- MichaelBurge 5y ago
  No there isn't. It is a fundamental property of CS that all bitstrings with the same bits are equivalent for computing. So if file 1 is a bitstring, you don't modify the bits to produce file 2, then file 2 has the same bitstring and will be processed the same as file 1.
  - vba616 5y ago
    Mr. McGuire : I just want to say one word to you. Just one word. Benjamin : Yes, sir. Mr. McGuire : Are you listening? Benjamin : Yes, I am. Mr. McGuire : Metadata. (also see https://en.wikipedia.org/wiki/Resource_fork https://en.wikipedia.org/wiki/Resource_fork) "The Windows NT NTFS can support forks (and so can be a file server for Mac files), the native feature providing that support is called an alternate data stream."
  - nfoz 5y ago
    Not the parent and not sure what s/he meant, but one could imagine software that borks when there are invalid (but nonobvious) characters in the filename, for example. Or file permissions or other extended filesystem attributes / resource forks if somehow you can get them delivered to the teacher that way.
    - y4mi 5y ago
      The files are also often delivered via USB Stick which are usually formatted with a filesystem without bitrot detection. That would be indistinguishable from someone manually screwing with the file too. You can never be certain wherever the damage was caused by bitrot or a person screwing with the file, but certain patterns are very unlikely to occur naturally so a reasonable guess is at least somewhat possible
      - noduerme 5y ago
        My whole form of copy protection on AIR apps through about 2013 was basically to have the login system side-load another SWF once the user logged in - but the SWF's bytecode would be tweaked and corrupted in a way that required a valid response to the login to de-corrupt on the client side before it could be executed. Probably just the fact that you would've had to decompile the side-loader was enough to prevent it from being stolen.
        Yoric 5y ago
        Hey, I had a similar copy protection scheme for binaries during the 90s :)
        noduerme 5y ago
        Hah. It's pretty awesome to hear that from a Firefox dev. I look back at it and wonder... what was the point? I think I was just having fun. I even went as far as having two "patches", where the first one made the software work but without the second one, it would send your VM and browser into a death loop after about 30 seconds. It was just the right amount of time to cause an SWF decompiler on Windows to crash the whole system. Anyone who wanted it badly enough would have gotten it, and I doubt anyone ever put in the effort to hit that spiral, so I must have just been entertaining myself ;)
  - yread 5y ago
    you could just truncate it at page (4k multiple) boundary. very hrad to prove intent
bryanrasmussen 5y ago
how could he be sure the kid did it though, seems like he should have better proof than the file was screwed up.
- qq66 5y ago
  The hex was clearly corrupted manually, something had been typed there. I don't think it was just the word "fuck" but I think the word "fuck" was in it. Was decades ago.
  - zinekeller 5y ago
    Ah, it was only "hjfsagufsaiugasfigsaigsg78wafg7fas fuck you teacher! fhadiuofashofhsaibsaiu" Notepad corruption? Huh, that's a fun one! /s But seriously, I'm impressed by that teacher.
sillysaurusx 5y ago
Back in high school in ye olden days of 2003, the trick was to put a powerful magnet on your floppy disk prior to turning in the assignment. Floppy disk failures weren’t too uncommon, so it was hard to prove intent. Frankly I’m amazed computers were trusted by anybody back then. Imagine if iCloud randomly corrupted 1 in 100 photos.
- endymi0n 5y ago
  Seriously, the magic of error correction is hardly appreciated or noted by younger hackers these days. I had one important project (I don‘t remember anymore which one it was), so I put it on THREE 3,5‘‘ disks, one after each other. All three were unreadable by the time I arrived. I was devastated. (note I had heard stories about rotating current brakes ruining disks so I took care not to go by rail, must have been something else)
  - londons_explore 5y ago
    Either the drive you wrote the disks on, or the drive you used to read them, were misaligned. Putting the disks back in the original drive and they probably would have been readable.
    - scsilver 5y ago
      And they computers don't have a sense of humor.
  - bambax 5y ago
    Not exactly the same story, but there was this one time when I was working on a long document, several days work, on an Amstrad PPC 640 (this was the early 90s). Saving the file on a floppy took around 1 minute I think (maybe more) so I didn't do it often and had no copy or backup of any kind. It was around midnight, I was done and hit save. I had an external monitor, and for no particular reason, decided to move it around during the save. It was big and heavy, and while moving it I accidentally hit the power switch of the PC. Powering off the machine during disk write destroyed everything. I couldn't believe it, I stared at the machine for a while. Then I spent the rest of the night recreating the document from memory, while making frequent copies on different disks. It was a horrible moment that I remember vividly, but it taught me a valuable lesson. I never again lost any file for lack of appropriate backup.

by qq66 5y ago

Handytinge 5y ago

What could parent complain about? I'm lost.

ARandomerDude 5y ago

That man believed in teaching more than what was in the textbook. Kudos for the lesson in integrity.

suifbwish 5y ago

There are ways to corrupt a file without messing with the hex content of the file

MichaelBurge 5y ago
No there isn't. It is a fundamental property of CS that all bitstrings with the same bits are equivalent for computing. So if file 1 is a bitstring, you don't modify the bits to produce file 2, then file 2 has the same bitstring and will be processed the same as file 1.
- vba616 5y ago
  Mr. McGuire : I just want to say one word to you. Just one word. Benjamin : Yes, sir. Mr. McGuire : Are you listening? Benjamin : Yes, I am. Mr. McGuire : Metadata. (also see https://en.wikipedia.org/wiki/Resource_fork https://en.wikipedia.org/wiki/Resource_fork) "The Windows NT NTFS can support forks (and so can be a file server for Mac files), the native feature providing that support is called an alternate data stream."
- nfoz 5y ago
  Not the parent and not sure what s/he meant, but one could imagine software that borks when there are invalid (but nonobvious) characters in the filename, for example. Or file permissions or other extended filesystem attributes / resource forks if somehow you can get them delivered to the teacher that way.
  - y4mi 5y ago
    The files are also often delivered via USB Stick which are usually formatted with a filesystem without bitrot detection. That would be indistinguishable from someone manually screwing with the file too. You can never be certain wherever the damage was caused by bitrot or a person screwing with the file, but certain patterns are very unlikely to occur naturally so a reasonable guess is at least somewhat possible
    - noduerme 5y ago
      My whole form of copy protection on AIR apps through about 2013 was basically to have the login system side-load another SWF once the user logged in - but the SWF's bytecode would be tweaked and corrupted in a way that required a valid response to the login to de-corrupt on the client side before it could be executed. Probably just the fact that you would've had to decompile the side-loader was enough to prevent it from being stolen.
      - Yoric 5y ago
        Hey, I had a similar copy protection scheme for binaries during the 90s :)
        noduerme 5y ago
        Hah. It's pretty awesome to hear that from a Firefox dev. I look back at it and wonder... what was the point? I think I was just having fun. I even went as far as having two "patches", where the first one made the software work but without the second one, it would send your VM and browser into a death loop after about 30 seconds. It was just the right amount of time to cause an SWF decompiler on Windows to crash the whole system. Anyone who wanted it badly enough would have gotten it, and I doubt anyone ever put in the effort to hit that spiral, so I must have just been entertaining myself ;)
- yread 5y ago
  you could just truncate it at page (4k multiple) boundary. very hrad to prove intent

bryanrasmussen 5y ago

how could he be sure the kid did it though, seems like he should have better proof than the file was screwed up.

qq66 5y ago
The hex was clearly corrupted manually, something had been typed there. I don't think it was just the word "fuck" but I think the word "fuck" was in it. Was decades ago.
- zinekeller 5y ago
  Ah, it was only "hjfsagufsaiugasfigsaigsg78wafg7fas fuck you teacher! fhadiuofashofhsaibsaiu" Notepad corruption? Huh, that's a fun one! /s But seriously, I'm impressed by that teacher.

sillysaurusx 5y ago

Back in high school in ye olden days of 2003, the trick was to put a powerful magnet on your floppy disk prior to turning in the assignment. Floppy disk failures weren’t too uncommon, so it was hard to prove intent. Frankly I’m amazed computers were trusted by anybody back then. Imagine if iCloud randomly corrupted 1 in 100 photos.

endymi0n 5y ago
Seriously, the magic of error correction is hardly appreciated or noted by younger hackers these days. I had one important project (I don‘t remember anymore which one it was), so I put it on THREE 3,5‘‘ disks, one after each other. All three were unreadable by the time I arrived. I was devastated. (note I had heard stories about rotating current brakes ruining disks so I took care not to go by rail, must have been something else)
- londons_explore 5y ago
  Either the drive you wrote the disks on, or the drive you used to read them, were misaligned. Putting the disks back in the original drive and they probably would have been readable.
  - scsilver 5y ago
    And they computers don't have a sense of humor.
- bambax 5y ago
  Not exactly the same story, but there was this one time when I was working on a long document, several days work, on an Amstrad PPC 640 (this was the early 90s). Saving the file on a floppy took around 1 minute I think (maybe more) so I didn't do it often and had no copy or backup of any kind. It was around midnight, I was done and hit save. I had an external monitor, and for no particular reason, decided to move it around during the save. It was big and heavy, and while moving it I accidentally hit the power switch of the PC. Powering off the machine during disk write destroyed everything. I couldn't believe it, I stared at the machine for a while. Then I spent the rest of the night recreating the document from memory, while making frequent copies on different disks. It was a horrible moment that I remember vividly, but it taught me a valuable lesson. I never again lost any file for lack of appropriate backup.