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Old 05-07-2010, 12:02 PM   #8
Giuseppe Chillem
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Quote:
Originally Posted by speakingtohe View Post
Just curious. How do you tell the file is physically the same.? File name and size or scanning the whole book? If file name and size that is not foolproof but pretty easy for a person to do manually.
Helen
If you have a directory full of e-books, each ebook has size and CRC32 which are always the same. If you store the CRC32 into the DB of Calibre and you sercch for it (and file size) during a new import you are able to match with 100% accurancy if the file is duplicate and already been imported.
CRC32 an filesize is the way software which search for duplicated files adopt to find duplicates on the hard drives (a good program for this is CSPY, "Clone Spy")

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