> On Oct 19, 2015, at 2:46 PM, Johnny Billquist <b...@update.uu.se> wrote:
>
> On 2015-10-19 20:43, Paul Koning wrote:
>>
>>> On Oct 19, 2015, at 2:30 PM, Johnny Billquist <b...@update.uu.se> wrote:
>>>
>>> On 2015-10-19 19:42, Paul Koning wrote:
>>>> ...
>>>> CTERM was an attempt to wrap a single protocol around the terribly
>>>> inconsistent semantics of the terminal drivers in all the DEC operating
>>>> systems, and to export as much as possible to the server end. ...
>>>
>>> An interesting way to describe it.
>>> I've always looked at CTERM as an RPC service that essentially have all the
>>> functions of the VMS terminal driver. Makes it easy to implement in VMS, as
>>> you have a 1:1 mapping. Makes it horrible for everyone else, since other
>>> systems do not have the same functionality in the terminal driver, and now
>>> have to implement all the remote procedure calls of the VMS terminal
>>> driver, and somehow map that into how the native terminal driver works...
>>
>> You can certainly view it as an RPC, and given that Cterm ended up basically
>> doing VMS, looking at it as the RPC version of the VMS terminal driver is
>> reasonably accurate. But the original version aimed to support both VMS and
>> TOPS-20 as primary clients, and other operating systems as well. So it was
>> supposed to be an RPC version of the union of all terminal drivers. Which
>> means that a full CTERM server (as opposed to client) would be hard to do
>> for everyone, even VMS.
>
> The amount of swearwords from TOPS-20 people exceed all others combined, in
> my experience. So if they intended CTERM to be something reasonable for
> TOPS-20 it was an utter failure. :-)
Yes.
> And it's really silly and sad, considering that something like telnet is very
> simple and straight forward, and can be done right on both VMS and TOPS-20,
> and will in the end work much better for people connecting from one to the
> other, than using CTERM...
> (I have the same issues with CTERM under RSX. telnet makes so much more
> sense.)
Sure, telnet in character mode (not line mode) works for everyone because it
doesn't try to export any real work to the server end.
For the same reason, the older remote terminal protocols (the set of 4, before
Cterm was perpetrated) work great. Those simply export primitives suitable for
the OS in question. Simple line mode with the ability to switch to character
mode for RSTS, character mode all the time for TOPS-20, and a much simpler RSX
and VMS terminal driver QIO RPC for those two operating systems. All these are
so easy that RSTS can implement them all, quite unlike Cterm.
paul
