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What Cinderella did - sorting the bytes


 
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# 8  
Old 12-01-2007
Quote:
Originally Posted by fedusr
Yes, it's corrupt (and the only backup I have):

# tar -xf backup
tar: This does not look like a tar archive
tar: Skipping to next header
tar: Error exit delayed from previous errors
#



Quote:
Originally Posted by fedusr
Actually I applied gzip ('z' option).
I think you also need a z to extract it then. You might try that. I rather doubt it will work, but it's easy enough to try.

Examine the octal dump to find out how the listing is clustered. Is it arranged as lines? Is is always a buffer of exactly 8196 characters? You might be able to develop a workable algorithm with more information.
# 9  
Old 12-01-2007
Quote:
Originally Posted by Perderabo
I think you also need a z to extract it then. You might try that. I rather doubt it will work, but it's easy enough to try.
"Reading compressed archive is even simpler: you don't need to specify any additional options as GNU tar recognizes its format automatically." (GNU tar manual)

Quote:
Originally Posted by Perderabo
Examine the octal dump to find out how the listing is clustered. Is it arranged as lines? Is is always a buffer of exactly 8196 characters? You might be able to develop a workable algorithm with more information.
Allright, that will be my Sunday amusement tomorrow. Again, thank you for your support.
# 10  
Old 12-01-2007
Maybe you could take a test directory of some data and tar it correctly; and then using the same test directory, tar it incorrectly.

Then, use a file comparison too to see exactly how the tar file in error was structured and if it is feasible to repair.

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