Re^3: Calculating corruption

You asked how to check if a file is corrupted.

Store a checksum of the encrypted file, best together with the file, maybe appended to the end.

If you meant something different, you may want to try to explain it...

Cheers Rolf

_{(addicted to the Perl Programming Language and ☆☆☆☆ :)}

update

btw: Trying to decrypt it should be enough, I'm not aware of any common encryption which can be reversed if corrupted.

Comment on Re^3: Calculating corruption

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Re^4: Calculating corruption by james28909 (Deacon) on Oct 18, 2014 at 21:56 UTC
but storing a checksum of the encrypted file will be useless wouldnt it? because i am not sure if even the first file will be corrupted. i wouldnt want to generate a hash for a corrupted file to check with. i need to check the first original file for corruption. and like i say, the file cannot be decrypted because the keys to decrypt it are unknown afaik :l the next idea i had would be checking it for randomness. an excrypted files should be very low or null on repeating byte characters, shouldnt it? but how do you check a file for byte character randomness, or randomess at all? <.<	[reply]
Re^5: Calculating corruption by Jim (Curate) on Oct 18, 2014 at 23:42 UTC
There's no solution to the problem you've described. And I don't loosely mean there's no tractable solution to the problem; I mean there's utterly no solution at all. UPDATE: I just realized someone else has already made this same point elsewhere in the thread.	[reply]
Re^5: Calculating corruption by LanX (Saint) on Oct 19, 2014 at 11:03 UTC
If you can't checksum the file right after encryption then better try Dowsing ! Anyway I expect most encryption methods to detect corruptions by themselves, hence a pretty fruitless discussion. Cheers Rolf _{(addicted to the Perl Programming Language and ☆☆☆☆ :)} PS: Talking about statistics, ignoring users with many trailing digits proofs to be an excellent rule of thumb to avoid "corrupted" (and cryptic) questions. Thanks! :)	[reply]
Re^6: Calculating corruption by james28909 (Deacon) on Oct 20, 2014 at 02:59 UTC
the best thing i can do is provide proofs to what i am saying. tomorrow i will compile a list of outcomes on these files. :) and you can judge for yourself	[reply]