On Thu, Jul 2, 2026 at 5:20 AM Lars Brinkhoff via cctalk
<[email protected]> wrote:

> Sometimes there is more data after the two tape marks.  Sometimes
> it's important data.

Sometimes it's sneaky secret data. Towards the end of the Classic HP
3000 era, HP grew tired of making customized SUBSYS tapes (that only
included the set of subsystems the customer had purchased) to send to
every supported machine whenever there was an OS version update. So
they came up with a new HP UPDATE distribution mechanism that involved
sending the same tapes to everyone. These tapes secretly contained the
full set of updated subsystem products hidden after the first double
tape mark.

The customer would restore "everything" on the tape which appeared to
be only nine little files (from a two reel tape set lol) including the
update program. An obfuscated file contained signatures (like a
filename, or procedure name) of installed products so the program
could figure out which products were already on the system and which
it would then proceed to update by pulling files off the second :STORE
image hiding after the first one.

Old HP was always so cute when they tried to be sneaky.

They only got to use this distribution mechanism once, as part of the
last-ever Classic MPE/V release (Version 40).

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