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Using the journaling module, any of the previous corrupted states would be either rolled back or completed upon volume remounting. This is made possible because, prior to performing any low-level FAT operation, the journaling system logs recovery information in a special file called the journal file. By reverting or completing successive underlying low-level FAT operations, the journaling module also allows top-level FAT operations to be reverted or completed, thus making them atomic (see section 12-6 “Optional Journaling System” Optional Journaling System). In our previous example, the journaled rename operation could only have on of the two following outcomes:
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