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From: Terry Lambert <terry@lambert.org>
Message-Id: <199512191812.LAA14896@phaeton.artisoft.com>
Subject: Re: Help with telnet, flow control, and IXON.
To: mbarkah@hemi.com (Ade Barkah)
Date: Tue, 19 Dec 1995 11:12:42 -0700 (MST)
Cc: hackers@FreeBSD.org
In-Reply-To: <199512191105.EAA02661@hemi.com> from "Ade Barkah" at Dec 19, 95 04:05:40 am
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> [Background]
> 
> We have users logging into a FreeBSD 2.0.5-R machine by modem via
> a terminal server. Users connect from the terminal server to the
> FreeBSD box via `telnet', with the escape character supressed so
> they can transfer files (this all works fine.)
> 
> [Problem]
> 
> Users running certain applications on the FreeBSD box sometimes
> get garbled output. To be exact, the garbled output occurs soon
> after an application turns off IXON in the terminal's c_iflag.
> The user gets a string of garbled output, then everything fixes
> itself.
> 
> Note, if a user telnets to the FreeBSD box via an intermediate
> site, the garbling disappears. It also never garbles when the
> user is running under `script'.

Probably this is old vs. new termio.

In the old days, BSD didn't support turning off parity very well.

Probably your intermediate site's telnet is stripping the high (parity)
bit.

You haven't explained how the output is garbled, but if it's odd (high
bit value) characters, this is probably what's going on.

You need to make sure the programs use the *new* termios mechanism for
setting/resetting XON.


					Terry Lambert
					terry@lambert.org
---
Any opinions in this posting are my own and not those of my present
or previous employers.