The close routine writes the data set trailer labels with the identifiers EOF1 and EOF2. Except for the label identifiers and the block count, these labels are created in the same manner and with the same content as the data set header labels.

The close routine writes two tape marks following the trailer labels. If user labels are to be written, the tape marks follow the user trailer labels. If another data set is added to the tape (multiple data set organization), its HDR1 label overlays the second tape mark. The close routine passes the block identifier on a cartridge tape to the installation's tape end-on-volume exit. DFSMSrmm saves this information. See z/OS DFSMS Installation Exits.