Announcing TCP/IP for RSX-11M-PLUS

Johnny Billquist bqt at update.uu.se
Wed Jan 14 16:30:32 CST 2015


On 2015-01-14 23:21, Mouse wrote:
>>>> If you happen to have an RSX system which you are conneting from,
>>>> you can also try getting the BQTCP.TAP tape image.  Such an image
>>>> will not transport cleanly to a non-RSX system, however.
>>> I'm curious: why wouldn't it?  [...]
>> Nah.  The problem is simpler than that.  It all relates to the fact
>> that files under RSX are very different than under Unix.  File in RSX
>> are organized in different ways.  And virtual tapes are of variable
>> sized records.  So, how would I communicate that across FTP?  And the
>> actual length of those records?
>
> FTP has a lot of capabilities many people are totally unaware of; see
> RFC 959.  (Admittedly, depressingly many people are unaware FTP even
> _exists_....)  For what you sketch, I'd suggest record structure
> (STRU R) and block mode (MODE B).

Oh how I wish. Have you tried giving those command in an ftp client 
under Unix? :-)

Essentially, for transfer to/from Unix systems, you are stuck with STRU 
F, MODE S

Since the struct and mode abilities in the FTP protocol will not easily 
cover enough anyway, I decided to do a similar trick I noticed VMS is doing.

So I support a "STRU O RSX" command, will will enable the extra bells 
and whistles needed to transfer files properly between RSX systems.

>> Essentially any binary file under RSX cannot be transferred over FTP,
>> [...]
>
> Sounds to me as though the truth is more like, cannot be transferred to
> or from typical "everything is a bag of bytes" Unix-mindset FTP
> implementations.  Unless there's something particularly arcane you
> haven't hinted at, I don't see anything that would prevent transferring
> them over standard FTP, given a server and client that actually
> understand that FTP is more than a bag-of-bytes transfer tool.

No, you are right. And that is what I do when talking between a properly 
able FTP server and FTP client.

Since that essentially boils down to an RSX system talking to an RSX 
system, I did it with an extension that makes it easy for me. The effect 
when talking to other systems are the same. Using the existing stuff in 
RFC 959 would only mean I would have problems transferring between RSX 
systems, and still not able to transfer to anything else anyway.

So it's nothing really arcane. It's just that I will not be able to 
transfer something like a binary native RSX file to a non-RSX system. 
But that was almost expected anyway.

	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


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