System for modifying data read out from storage device and only overwriting those components of the data read out which differ from the modified data

摘要

The method and apparatus described are distinguished in that the data read out and the modified data are compared with one another before the data read out are overwritten with the modified data. Only those components of the data read out which differ from the modified data are overwritten. This is an extremely simple way of preventing changes to the stored data that were made between the time of reading out the data and overwriting the data from being unintentionally reversed.