SFV files contain CRC32 checksums which can be used to determine whether or not the files listed were downloaded correctly. So, after downloading a set of files, you can use a program like SuperNZB to calculate the CRC32 checksums and then compare them to the checksums in the SFV file. If they match, then everything was downloaded perfectly.
If you open an SFV file with Microsoft Word, or any other word processor that can run scripts, it is possible that a virus in the SFV could get you. When downloading text files, it’s always a good idea to open them with a bare-bones text editor like NotePad on Windows and TextEdit on the Mac, both of which come free with your computer.
Here is a sample SFV file:
------------ Begin Sample SFV File Listing ------------ ;15000000 08:52.45 2005-07-28 Some.File.avi.part01.rar ;15000000 08:53.06 2005-07-28 Some.File.avi.part02.rar ;15000000 08:53.28 2005-07-28 Some.File.avi.part03.rar ;15000000 08:53.49 2005-07-28 Some.File.avi.part04.rar ;15000000 08:54.12 2005-07-28 Some.File.avi.part05.rar ;15000000 08:54.35 2005-07-28 Some.File.avi.part06.rar ;15000000 08:54.57 2005-07-28 Some.File.avi.part07.rar ;15000000 08:55.19 2005-07-28 Some.File.avi.part08.rar ;15000000 08:55.40 2005-07-28 Some.File.avi.part09.rar ;15000000 08:56.01 2005-07-28 Some.File.avi.part10.rar ;15000000 08:56.23 2005-07-28 Some.File.avi.part11.rar ;15000000 08:56.44 2005-07-28 Some.File.avi.part12.rar ; 2432113 08:56.48 2005-07-28 Some.File.avi.part13.rar ; 13376 08:59.32 2005-07-28 Some.File.avi.par2 ; 397444 08:59.32 2005-07-28 Some.File.avi.vol00+01.PAR2 ; 794812 08:59.32 2005-07-28 Some.File.avi.vol01+02.PAR2 ; 1576248 08:59.32 2005-07-28 Some.File.avi.vol03+04.PAR2 ; 3125820 08:59.32 2005-07-28 Some.File.avi.vol07+08.PAR2 ; 6211664 08:59.32 2005-07-28 Some.File.avi.vol15+16.PAR2 ;11204548 08:59.32 2005-07-28 Some.File.avi.vol31+29.PAR2 ;15442596 08:59.32 2005-07-28 Some.File.avi.vol60+40.PAR2 Some.File.avi.part01.rar 5079A617 Some.File.avi.part02.rar 27001333 Some.File.avi.part03.rar C3B6525B Some.File.avi.part04.rar B8C8C580 Some.File.avi.part05.rar EAFB98CB Some.File.avi.part06.rar DB963752 Some.File.avi.part07.rar EC26E01A Some.File.avi.part08.rar 837AE97F Some.File.avi.part09.rar E580FB75 Some.File.avi.part10.rar 838EFC3C Some.File.avi.part11.rar A45455D5 Some.File.avi.part12.rar FF34484F Some.File.avi.part13.rar B963FE25 Some.File.avi.par2 61443265 Some.File.avi.vol00+01.PAR2 25FD04F2 Some.File.avi.vol01+02.PAR2 2C354FD1 Some.File.avi.vol03+04.PAR2 4FDE31A3 Some.File.avi.vol07+08.PAR2 1EEFB660 Some.File.avi.vol15+16.PAR2 FB8481AA Some.File.avi.vol31+29.PAR2 95A49937 Some.File.avi.vol60+40.PAR2 286279AE ------------ End of Sample SFV File Listing ------------
The files shown above are a typical RAR/PAR set. Any lines of the SFV file that begin with a semicolon are comments and can be ignored. So, the first relevant line is: “Some.File.avi.part01.rar 5079A617.”
“Some.File.avi.part01.rar” is the name of the file, and “5079A617″ is the value calculated when the data from the file is run through the CRC32 algorithm. “5079A617″ is calculated on the computer of the person who posted the file. If the copy of “Some.File.avi.part01.rar” that you now have yields a value of “5079A617″ then you have an exact copy.
Once you have SuperNZB installed, just click the “SFV” button on the main window:
(Note: The screenshot above, and the demo video below were made on Windows, however the program looks identical on the Macintosh.)
Here is a 5 minute demo video:
CRC32 can also be used to find duplicate files on your system. DupeNuker keeps a database of CRC32 “fingerprints” so you can quickly tell if a new file is one you already have, or have already seen before.
do you HAVE to do this for every sfv file you get ? i dont really get it… why do you have to do do this?
Sharpie,
You don’t have to do it. Some people want to make sure that every bit is where it’s supposed to be. It just depends on your preference, and how critical the file is. For example, if you download a podcast, listen to it, and then throw it away, it’s not very critical if a few bits got flipped while you were downloading it. But if you download a piece of software, and the bits don’t add up, then somebody may have tampered with it, and you might be installing a trojan.
Admin
sometimes when i download my 1080p x264 films using jdownloader or some via bittorrent, they are compressed into multiple rar files and then they contain a sfv file at the bottom of the folder with all of the rar files, now i at least know wut its for, i never ever thought of deleting it before extracting anyway just incase u never know so just keep it till u extracted everything and then delete the sfv along with all of tha rars to get ur precious good lookin free space back on ur hdd homey
haha @x264 1080p dts downloader
I love your logic, and i feel i am the same way.