> This hypothetical interface + matching software would be intended for > archiving old tapes and/or making new copies from archived file > (i.e., to make new boot media for bringup of an old computer). Key > features would include preservation of block sizes (even if varying > arbitrarily) and file marks. I'm not sure if there's already a good > file format for that, and I have a dim memory of previously reading a > lament about common archival methods failing to preserve blocking.
The E11/SimH .tap formats are dead simple, and relatively complete as far as capturing the arrangement of the bits on tape. They retain block size, actual data, file marks, and have a provision for indicating errors encountered when reading the tape. There was a discussion recently (simh list?) about standardizing the behavior of the error marks. The format doesn't have a mechanism for preserving metadata. In the SimH variant, record lengths must be even. In the E11 variant, they on't have to be. Otherwise, the two are equivalent. Using dd to read tapes to disk discards the block size information. De
