DUPLEXING CONTROL SYSTEM

PROBLEM TO BE SOLVED: To provide a duplexing control system with which the file writing from an application is not inhibited during a file equalization processing and the file reading property of the application during file equalization processing is hardly deteriorated.SOLUTION: During the time in which data of a (N-1)th buffer 104 of a control system module 10 for which the writing is inhibited is added to a file 22 of a standby system module 20, a N-th buffer 104 holding data to which an application 13 requests the writing of a file of the control system module 10 is sequentially generated into the control system module 10. During the time in which the data of the N-th buffer 104 is added into the file 22 of the standby system module 20, when no writing request from the application 13 is generated, the equalization processing of all files is completed.