Par files


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Allow me to explain. PAR files stand for Parity files, and they are one of the best error-checking methods for my beloved newsgroups I've seen in a while. Anyway, the way I think of them is like an Ace when playing cards; it can be just about anything in that spanned RAR archive.

Say if I were to download a 220 meg MPEG file that is spanned across 15 RAR files that are 15 megs each, but what if .r01 is missing and .r06 is corrupt? Instead of begging the person who uploaded it to repost those files, I merely look to the .PAR files. If he posted 3 PAR files, that means I can repair any 3 files in the archive. 1 PAR = 1 RAR. If 4 RAR files are damaged and/or destroyed, you'll have to re-download at least one of them and hope it fixes it in this situation.

The program you need is called "Mirror". Right now it is at version 0.2.6, and can be obtained from here. It will scan the .PAR file, which is an index file, then check the spanned RAR archive it goes with, then the PAR files that hold the data. It will then let you restore any files if you need to.

I hope this has answered your question regarding PAR files. If I left out something, sorry about that, but 2 finals in 1 day + little sleep = frazzled brain.:cross:

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You need a par extractor ... no not an extractor, a rebuilder. Search on Yahoo. They are not a compression of a file, but rather a way to recover a missing file. Suppose you are missing file 2 of 10, and you have a .PAR file, a .P01 file, and a .P02 file. You would use .P01 to recover the second file. It first does a CRC, and if it does not find a match, it rebuilds the file using the other files and the par (it being your program :) )

I dont know the math behind it but i would like to know. I understand it is EXTREMELY complicated.

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