The EOV routine is entered when a tape mark is read, when the end of volume is encountered while writing, or when the processing program issues a force-end-of-volume (FEOV) macro. If you use the execute channel program (EXCP) technique, your processing program must issue an EOV macro to give control to the EOV routine after your program recognizes a tape mark or end of reel or cartridge. The EOV routine processes trailer labels on the current volume (or header labels if the tape is read backwards), and determines if additional volumes are needed to continue the data set. If another volume is needed, or another data set is concatenated, then the EOV routine handles the volume switching and processes the labels on the new volume. Otherwise, if the current volume is the last or only volume needed, then EOV gives control to the user's end-of-data routine that is specified in the DCB.

EOV routines also resolve conflicts in the same way as the open routines.

If DFSMSrmm is in use, then the function performed at OPEN and CLOSE is performed at EOV as well.