[Info-vax] SET TERMINAL /INQUIRE (was: Re: DECnet Phase IV broken after VSI update)

[VAXman- at SendSpamHere.ORG]

In article <slkr4j$8cc$1 at dont-email.me>, Stephen Hoffman <seaohveh at hoffmanlabs.invalid> writes:
>On 2021-10-30 23:00:00 +0000, Craig A. Berry said:
>
>> When you do, you may need to have a look at the part of SYLOGIN.COM 
>> that has the SET TERM/INQUIRE command.  In the boilerplate version that 
>> comes with VMS, a rather long list of device types are excluded from 
>> running that command, including "FT" which is what is   used by 
>> interactive SSH connections, so by default, VMS won't know what kind of 
>> terminal you have and lots of stuff doesn't work with terminal type 
>> "Unknown."  If you delete FT from the list, your interactive sessions 
>> will start getting the correct terminal type, but other things that 
>> tunnel over SSH may break.
>
>I'm guilty of most of that ginormous DCL abomination, as an earlier 
>wide-open SET TERMINAL /INQUIRE was blowing up too much, and the 
>terminal settings changes (particularly around performing that command 
>on the console, and around clearing screens, IIRC) were derailing the 
>regression tests. That DCL abomination because SET TERMINAL /INQUIRE 
>wasn't all that much past a box of rocks at its own intended job. That 
>all due to upward compatibility. And FT is (also) used for foreign 
>terminals, which'll blow up other stuff that uses FT.
>
>Pragmatically, ssh should have used its own terminal type, but that's 
>probably not going to change now.
>
>There are other issues lurking here, such as with the (lack of) 
>TT_ACCPORNAM handling allowing identifying the source of arriving IP 
>terminal connections.


$ sh term
Terminal: _FTA99:     Device_Type: VT200_Series  Owner: SYSTEM
Remote Port Info: ssh/ool-########.dyn.optonline.net:50130

   Input:    9600     LFfill:  0      Width: 132      Parity: None
   Output:   9600     CRfill:  0      Page:   24

Terminal Characteristics:
   Interactive        Echo               Type_ahead         No Escape
   Hostsync           TTsync             Lowercase          Tab
   No Wrap            Scope              No Remote          Eightbit
   Broadcast          No Readsync        No Form            Fulldup
   No Modem           No Local_echo      No Autobaud        No Hangup
   No Brdcstmbx       No DMA             No Altypeahd       Set_speed
   No Commsync        Line Editing       Overstrike editing No Fallback
   No Dialup          Secure server      No Disconnect      No Pasthru
   No Syspassword     No SIXEL Graphics  No Soft Characters No Printer Port
   Numeric Keypad     ANSI_CRT           No Regis           No Block_mode
   Advanced_video     Edit_mode          DEC_CRT            DEC_CRT2
   No DEC_CRT3        No DEC_CRT4        No DEC_CRT5        No Ansi_Color
   VMS Style Input    <CTRL-H> Backspace

I developed a product over a decade ago to add the ACCPORNAM info to FTA's
used with ssh.  I designed it to be flexible for site needs by providing a
set of "formatters" that can be specified to modify how the remote info is
presented in the ACCPORNAM field.

-- 
VAXman- A Bored Certified VMS Kernel Mode Hacker    VAXman(at)TMESIS(dot)ORG

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