On 01/27/2017 03:41 PM, Stan Sieler wrote: > My recollection is that DDS-1 (and perhaps -2?) had 'set marks' that > few people knew about, and even fewer ever used. The explanation I > recall is that the drive could do a "forward to next setmark" *much* > faster than "forward to next EOF". (BTW, when reading, a setmark was > reported like an EOF (although if you requested extra status you > could tell them apart).)
I believe that ANSI refers to them as "partitions", IIRC, defined by a special page in the MODE_SELECT command. Each partition has its own EOD. Using the MODE_SENSE code page 11h will turn up information as to a tape bing multi-partitioned. Few people made use of the partitioning feature, as far as I know. All of this is doubtless covered by one or several ANSI X3B5 pubs. --Chuck
