2 May
2002
2 May
'02
11:12 a.m.
On 2002.05.02 21:08 Raymond Moyers wrote:
Unix will treat any device as a stream of bytes
And that is not appropriate for tapes. You have files on a tape. A tape
file consists of records (blocks). The records may be different in
length from file to file. Unix does not know about that, so the
information about the record size is lost. But many boot Proms rely on
particular record sizes.
And keep in mind that streaming tapes for backup (i.e. that what we know
as tape today) is only a "simplification" of a real tape station. A real
tape station can handle tapes in block addressable mode, exactely as a
disk! You have block devices for this tapes and you can put a regular
file system on it, and mount that file system like a disk.
(I saw one of these beasts running on a CDC Cyber 960 supercomputer on
the VCFe last weekend. Really impressive! That litle Cray EL98 beneath
the CDC looked like a toy compared to that dinosaur.)
--
tsch??,
Jochen
Homepage: http://www.unixag-kl.fh-kl.de/~jkunz/