[Simh] Announcement: back10

[Rich Alderson]

> From: Lars Brinkhoff <lars at nocrew.org>
> Date: Tue, 14 Feb 2017 10:42:00 +0100

> Johnny Eriksson wrote:

>> This is very much a work-in-progress, so things might change.  If
>> you have any opinion on how things should work, please let me know.

> If there's one thing I'd wish for, it would be for a standard encoding
> of binary 36-bit data into octets.  FTP uses high density format.
> Magtapes use core dump format.  ITS files and itstar use the evacuate
> format.  Then there's the ANSI-ASCII/KERMIT-36 5x7+1 format.  Let's not
> bring up disk images or 7-track and paper tapes.

> Converting between all these is a small cottage industry.

Personally, I'd vote for coredump format, as it's the common denominator
among Tops-10 and its derivatives (SAIL's WAITS, Tymshare's TYMCOM-X, the
CIS monitor) and TOPS-20, with utilities to convert into the others if
necessary (which it rarely is).

Is the evacuate format really used in ITS, or is it an artefact of putting
ITS files on Unix file systems?  That is, if a tape were simply copied via
a dd-style utility from a evacuated file, could ITS do anything with it?
Modulo record lengths as in SimH or E11 or DECUS tape-to-disk formats, a
coredump tape image can be dd'd directly to a physical tape, and vice versa.

                                                                Rich