David RossDavid Ross 522 bronze badges one one The SUB is undoubtedly an artefact of CP/M, exactly where it absolutely was utilized as an EOF marker (CP/M "duration" was blocks, not bytes). MSDOS was intended in order to browse CP/M data files, & because it was likely at some time that CP/M will be utilized to read the resuts from MSDOS, the opport