Re: System UICs

On 11 Jun 2024 21:15:57 -0400, Rich Alderson wrote:

TOPS-20, not Tops-10.

Ah. So “< ... >” was an idea copied from BBN, not DEC home-grown?

Did TOPS-10 allow “( ... )” in place of “[ ... ]”? Because I remember
RSTS/E did.

... where a hierarchical directory specification could be up to 39
characters long, and a file name and file type string cold be up to
39 characters long. The version was a decimal number in the range
1--131071.

Signed 18-bit version numbers, of course.

Interesting that VMS should have reduced the filename length to 9-dot-3 (à
la RSX?) in initial versions, then increased it again to 39-dot-39 in VMS
V4.

In the TENEX predecessor to TOPS-20, the separator for the version
number was a semicolon rather than a period.

How odd that DEC should have changed it to a dot in TOPS-20, then brought
back the other form as well for VMS ...

One little nicety about version specs was that the DELETE command insisted
on them, whereas most other commands didn’t care. This was a subtle way of
making file deletion take a little bit of extra mental effort to invoke,
as befitting its potentially dangerous status. (Better than those tedious
“Are you sure?” confirmation messages that are all too commonly used.)

However, some users took this to mean you actually had to put an explicit
version number in, when all you had to do was have the semicolon present
(or an extra dot), and that would mean “the most recent version” as usual.