An Automatic Intercept System data base of up to a half-million changed or disconnected telephone numbers is updated, corrected, verified, abstracted, restructured, and restored through the actions of a collection of function-oriented subprograms. These subprograms run in the base-level main program loop under their own monitor which also controls interruptlevel accesses to the asychronous disc memory. The monitor together with the set of subprograms provides a file administration capability which responds to both machine stimuli, such as timed entries or trouble indica tions, and human requests initiated from teletypewriters.