stty, SCO, clear EOL

[Bob Rasmussen]

See post at bottom.

On Fri, 15 Jul 2016, Joe Chasan via Filepro-list wrote:

> On Fri, Jul 15, 2016 at 09:02:34AM -0500, Bob Rasmussen via Filepro-list wrote:
>> I'm dusting off old memories here, in response to a customer, and I
>> need some help. Customer connects from Anzio on Windows to SCO 6,
>> runs filePro (not sure of version). Says if he connects via telnet,
>> all is good, but if he connects via SSH, when he types ctrl-O, it
>> doesn't clear to end of line. Emulation type is SCOANSI.
>>
>> The difference boils down to the stty setting "iexten". It's off in
>> telnet (not sure what initializes this); ON in SSH (set by Anzio).
>> In both cases, flush = ^o.
>>
>> Here's my analysis:
>>
>> * When iexten is on, UNIX gets the ctrl-O and deals with it somehow;
>>
>> * When iexten is off, UNIX passes the ctrl-O to filePro, which deals
>> with it as directed by the termcap entry;
>>
>> * When filePro sets the tty mode (in C) to "raw", it must not be
>> turning off the iexten switch;
>>
>> * This may not be an issue in Linux.
>>
>> Does this all make sense? Is my analysis correct?
>
> I have noticed it as well.  Not an issue in Linux or in OSR5 even.  Not an
> anzio issue either as other ssh clients do the same thing.  Tried
> digging into it on SCO side, the only mention I see of iexten is in
> maintenance pack 3 & 4 notes, and perhaps it makes more sense to you:
> | 308. SVR5 OSR5 ABI differences in termios ioctl c_lflag bit meaning. --
> | When running various OpenServer 5 binaries which used termio/termios
> | related ioctl's, certain operations were not working correctly.
> | Among these issues were the setting of the termio/termios c_lflag
> | TOSTOP, ECHOCTL, and IEXTEN flags, and the termios c_cc elements
> | VSTART, VSTOP, VDSUSP, and VREPRINT. The mentioned items have been
> | corrected, so the proper settings are done when running the
> | OpenServer 5 binary. (ID: 534510:1)
>
> A hack of a fix would be to "stty flush ''" or "stty -iexten" in
> /etc/profile, optionaly if $SSH_TTY is set, which I've done on occasion
> when annoyed.

Thanks for the details, Joe. It would appear that the issue is very 
dependent on which version/pack of SCO Open Server one is running.

There is a part of the SSH protocol, but not telnet, by which the client 
can set the initial stty modes of the server's pty session. Anzio does 
this, including (currently) setting iexten to ON. I'm thinking of changing 
this to OFF, to deal with this issue.

Does anyone see any downside?

Regards,
....Bob Rasmussen,   President,   Rasmussen Software, Inc.

personal e-mail: ras at anzio.com
  company e-mail: rsi at anzio.com
           voice: (US) 503-624-0360 (9:00-6:00 Pacific Time)
             fax: (US) 503-624-0760
             web: http://www.anzio.com
  street address: Rasmussen Software, Inc.
                  10240 SW Nimbus, Suite L9
                  Portland, OR  97223  USA