Patent ID: 7490196
Filing Date: 2009-02-10
Classification: G06F

Abstract:
1. A magnetic tape apparatus that stores data provided from an external device onto a magnetic tape, comprising: a magnetic tape access device that has a magnetic tape attachably and detachably set thereto, wherein the magnetic tape access device gains access to the set magnetic tape; a storage medium access device that has a storage medium attachably and detachably set thereto, wherein the storage medium access device gains access to the set storage medium; and a writing circuit that writes data provided from the external device onto the magnetic tape by controlling the magnetic tape access device, wherein when it is determined that data cannot be written onto the magnetic tape, the writing circuit switches a writing destination for the data from the magnetic tape to the storage medium, and writes address information and data following the data written onto the magnetic tape onto the storage medium by controlling the storage medium access device, wherein the address information indicates a position on the magnetic tape where the data should originally be written, and wherein the writing circuit determines that the data cannot be written onto the magnetic tape by: wherein, a reading destination determining circuit determines a timing at which to switch a reading source for data from the magnetic tape to the storage medium by reading the address information of a plurality of data records written on the storage medium before data in first data record of the plurality of data records is read from the magnetic tape or the storage medium; and a reading circuit that reads data from the magnetic tape by controlling said magnetic tape access device, checks after reading a predetermined amount of data, whether the timing determined by the reading destination determining circuit is reached, switches the reading destination for data to the storage medium at the timing determined by said reading destination determining circuit, and continues to read data from the storage medium, wherein the data read from the storage medium follows the data read from the magnetic tape, and wherein the writing circuit receives data written on the magnetic tape from the reading circuit.