PURPOSE: To prevent the malfunction of a program caused by a miscorrection by integrating the file allocation definitions for each file group and then changing these integrated definitions in a batch.

CONSTITUTION: In a file definition information processing state 1, the definition change data 2 is read and a file allocation definition file 4 is collectively updated based on a change program 3. In a dynamic file allocation processing state 7, a dynamic file allocation routine 6 is carried out in the first processing of an execution program 5. In the routine 6 the file 4 is read and the files 8 and 9 which are used by the program 5 are allocated. Thus the file definition information can be processed in a batch and the files are dynamically allocated in a program execution state. As a result, no miscorrection occurs.