Patent ID: 6594781
Filing Date: 2003-07-15
Classification: G06F

Abstract:
A computer comprising:a storage medium; and a controller coupled to said storage medium and capable of performing the following operations: (i) storing in said storage medium, in the case where data used for the operation of the computer itself is replaced by writing update data, the update data, updated data replaced by the update data, and non-updated data not yet replaced by the update data; (ii) reading, when executing data that is read out from said storage medium, the update data, if any, corresponding to the data to be read and the non-updated data corresponding to said data to be read in the absence of said update data; (iii) discarding the update data in response to a first instruction, if any, to restore said storage medium to its initial status; (iv) discarding the update stored in said storage medium after a designated arbitrary time point in response to a second instruction, if any, to restore said storage medium to the status at the designated arbitrary time point; and (v) replacing the updated data with corresponding update data in response to a third instruction, if any, to update said storage medium.