9 track tapes and block sizes

[Warner Losh]

On Fri, Oct 2, 2020, 12:05 AM Tom Hunter via cctalk <cctalk at classiccmp.org>
wrote:

> I have never figured out why Bob Supnik defined the magnetic tape
> containers (TAP files) with the one byte padding for odd length records.
> This seems very odd (pun intended).   :-)
> Even on a machine which couldn't write 32 bit numbers (the record lenght)
> on odd boundaries you could write the 32 bit number as 4 individual bytes.
> Does anyone know the reason?
>

RMS did this too.... if nothing else, it was in the water at Digital. But
it would have been faster to access than unaligned buffers...

Warner

Cheers
> Tom Hunter
>
> On Fri, Sep 18, 2020 at 9:17 AM Jeff Woolsey via cctech <
> cctech at classiccmp.org> wrote:
>
> > > Acoustically, the best tapes were the short-record "stranger" tapes.
> > > All sorts of interesting noise.  I could tell from across the room when
> > > someone was running the tape section of the Navy audit tests for COBOL
> > > just by the sounds.
> > >
> > MALET was also pretty good, reading and writing a bunch of blocks that
> > were one frame longer or shorter than the last.  Loud rising or falling
> > tone in the noisy computer room.
> >
> > --
> > Jeff Woolsey {{woolsey,jlw}@jlw,first.last@{gmail,jlw}}.com
> > Nature abhors straight antennas, clean lenses, and empty storage.
> > "Delete! Delete! OK!" -Dr. Bronner on disk space management
> > Card-sorting, Joel.  -Crow on solitaire
> >
> >
>