Recovery routines are given control when an error occurs during open, and close and end-of-volume processing. They provide data recoverability in case of an error that results in abnormal termination of your task. Data recoverability works in conjunction with your output trailer label routines by writing a tapemark after the last data written to the tape. This indicates the end of the output data set, so that you can save the records written before the error occurred. The tapemark is only written if an unrecoverable error occurs before your output trailer label routines have received control. If the error occurs during or after the execution of your trailer label routines, no tape mark is written.