The LMMREP service updates the directory to replace a member of a partitioned data set. The specified member is added if it does not currently exist. This service can be used with an ISPF library or an MVS™ partitioned data set. The LMINIT service with either ENQ(SHRW) or ENQ(EXCLU), the LMOPEN service with OPTION(OUTPUT), and the LMPUT service must be completed before you can use the LMMREP service.