[HECnet] DAP

[Johnny Billquist]

Hi.

On 2019-12-09 22:38, Thomas DeBellis wrote:
> I have been fixing some issues with the file access listening (FAL) 
> under Tops-20.  Briefly, it would crash on listing extremely large 
> directories and return incorrect byte sizes and counts for files under 
> certain circumstances.  It also did not support anonymous access as is 
> currently used in HECnet (blank user name).  There were other issues.

Hum. I don't think that is correctly described. Anonymous access as such 
does not exist. In VMS, there is a default account used if user/password 
is not provided. Same in RSTS/E I think.
In RSX, that mechanism does not exist. However, in RSX-11M-PLUS, you do 
have proxy access. That works by the serving side being able to map a 
remote user to some local user. In RSX that can be done with wildcards 
as well, so I've essentially setup that any remote user for which I do 
not have a more precise proxy entry, they go to a default proxy entry 
with maps to a specific local user.
But for that to work, both sides must support proxy access. So blank 
usernames is not what is going on, really...

> It's been a bit of a slog, the first two issues taking a considerable 
> amount of time to solve.  However, they're fixed and I've got some 
> prototype anonymous code running.  I would say that I am about 1 to 2 
> months away from an alpha test; the configurable restriction parsing is 
> nearly done, hooks remain to be into DAP functions and deployment 
> documentation to be written.
> 
> Questions:
> 
>  1. My own version of FAL appears quite dated; it only has edits to
>     Tops-20 V6.1 (1985), whereas the last monitor distributions were in
>     the 7 series.
>       * Does anybody have any source files later than that for Tops-20?

Not me. I seem to remember having seen sources for lots of stuff for 
Tops-10, and I'm trying to remember if I also saw Tops-20 code. Maybe 
someone else knows better.

>  2. What is the last version of DAP (any platform) for which a
>     specification exists?

The only specifications I know of are for DAP V5.6, which is dated 1980. 
Which really sucks, because clearly newer versions exist. RSX claims to 
be talking DAP V7.1 for example. But I haven't seen a spec for it anywhere.

>  3. The implementing DAP module (DAPLIB) appears even older, apparently
>     dating to V6.0, 1981 time-frame (which seems incorrect).  It 
>     supports DAP 5.6, for which I have the specifications.
>       * It does /not/ support $RENAME (ACCFUNC 3), which I found
>         remarkable.  Is $RENAME supported on all other platforms?

It's certainly supported under RSX, and without doubt also under VMS.

>       * I note that ACCFUNC 5 is reserved.  Is this used now?
>       * Is ACCFUNC 0 used?  For what?
>       * Is any ACCFUNC later than 8 defined?  What is the first free one?

No idea about those. I could go and check RSX sources when I have some 
time, but not tonight...

   Johnny

-- 
Johnny Billquist                  || "I'm on a bus
                                   ||  on a psychedelic trip
email: bqt at softjar.se             ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol