"i" flag in tar(1)

[march at m.cs.uiuc.edu]

I've heard mention of an undocumented command line option "i" in tar.
I believe it may be helpful in restoring corrupted tar files.  In 
particular ignoring blocks of zeros in the archive.  Can any of you tell
me exactly what it does?  

Thanks in advance.

				Steve

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Steve March						(H) 344-5303
Department of Computer Science, University of Illinois	(W) 333-7408 
							  
march at cs.uiuc.edu		                          
{uunet,convex,pur-ee}!uiucdcs!march                      
"Emotions are alien to me.  I'm a scientist." -- Spock, "This Side of Paradise"
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