[Simh] VAX Tape Emulation?

[Dennis Boone]

 > I think the documentation comment "cannot write variable-length
 > blocks and do not allow skipping forward over records between read
 > operations" was written when talking about the common cartridge tapes
 > that were available on 80s and 90s Unix workstations.  I don't recall
 > the name.  These things only supported fixed block size operations
 > and not variable record lengths (i.e. 80 byte tape labels, then
 > different sized data records, etc.).

Various QIC-defined formats.  Block size usually 512, though a few
computer companies apparently stuffed custom firmware into the drives to
get other block sizes.  (AS/400 did this, I think, and I've read that
some Prime machines did it, though the 50-Series tapes I've read have
been standard 512 blocks, with a controller-applied logical block
spanning scheme so the drive looked more like 9-track.)

De