RECORDING DEVICE, FILE MANAGEMENT METHOD, PROGRAM OF FILE MANAGEMENT METHOD, AND RECORDING MEDIUM FOR RECORDING PROGRAM OF FILE MANAGEMENT METHOD, ESPECIALLY CONCERNED WITH FORMING REFERENCE INFORMATION OF LOWER LAYER AND REFERENCE INFORMATION OF IDENTICAL LAYER AS WELL AS REFERENCE INFORMATION OF UPPER LAYER

摘要

PURPOSE: A recording device, a file management method, a program of the file management method, and a recording medium for recording the program of the file management method are provided to effectively use a function of reference information which indicates slots of an upper layer, a lower layer, and an identical layer to register and delete extract information, thereby easily perceiving a hierarchical structure to simply register and delete the extract information. CONSTITUTION: An index file is formed by continuous slots through extract information of the file and a folder. In each slot, reference information of an upper layer for indicating a slot of the upper layer, reference information of a lower layer for indicating a slot of the lower layer, reference information of an identical layer for indicating a slot of the identical layer, and valid/null flags showing validity or nullification are set. A recording device sets the valid/null flags so to be null, so that the slots are set to be empty slots.