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[JR@YUKON.SCRC.Symbolics.COM: Incremental tape re-use]
(The following unedited transcript of a first draft converstion.)
Date: Wed, 9 Aug 89 15:55 PDT
From: Richard Lamson <rsl@MAX-FLEISCHER.ILA-SF.Dialnet.Symbolics.COM>
Thank you Richard for the most intelligent comments on the net lately
(considering also my own).
Automating corporate memory is quite difficult without adequate tools,
as you probably know, Paul.
I know a man who, lacking 128 bytes, made it out of a 4-lb piece of
metal that had pins in it (wired into a configuration), which when
screwed into a larger, 40-lb box taking the place of a microcomputer,
provided the 128 bytes as a data read. This was 1955. What tools who?
I was part of Symbolics' Software Support
during at least three separate design efforts, none of which was
This means that it is hard, not that you did a good job.
This is made incredibly more difficult by the fact that
Symbolics is a bicoastal company.
No, this merely makes it more important that it be done.
Part of the problem is that "Corporate Memory" is a distinctly
associative memory, and the potential number of elements in the domain
of the relation is quite large. Even in the limited amount of corporate
memory that Symbolics passes out to the world, it is not always possible
to determine if the information you want is available: try discerning
from the documentation whether it is possible to append to cartridge
tapes, for example, and you will find nothing but this one tantalizing
Tape when done This controls what the dumper does with the tape
when it has finished passing over all the specified
pathnames. These are the available options:
Leave Leaves the tape positioned at
the end without rewinding it or
putting it offline. It declares the
dump finished. It facilitates more
dumping later, by leaving the
tape in the correct position for
using "Append to tape" in a later
The "Append to tape" option itself is not documented. Of course, the
documentation itself appears to have been produced by a writer who was
using the backup system to dump to a cartridge, so they didn't even see
the "Append to tape" question to document it (that question is
suppressed if you are dumping to cart). Note the figure in that
By the way, the answer to the original question about appending to
cartridges is that while appending is not possible, it IS possible to
cause the dumper to re-dump those files which were on the original tape
in limited circumstances. I recommend that people to consolidated dumps
back to a date certain rather than incremental dumps, at least some of
the time. For example, I do complete dumps approximately twice a year,
consolidated dumps back to the most recent complete (or sometimes to a
convenient consolidated, if a lot has changed) weekly, and incremental
tapes (approximately) daily.
(I am not up to commenting at the above, it is too beautiful to tamper
with, and too much like fire that it will burn my typing tips.)