Have you written a telnet application ????

[Dale]

Hey folks, I was wondering if someone out there had any ideas for me
since I'm stuck with my application that I'm using to drive a telnet
based application (screen scraper).

I started with socket.TelnetIO - a telnet implementation from GNU (see
below).

Inside there it says:
byte TELOPT_TTYPE = (byte)24; /* terminal type */

But when I run my application, right after it enters userid and
password I get:

%SET-W-NOTSET, error modifying VTA684:
-SET-I-UNKTERM, unknown terminal type
<TERMINAL SET>

I think the VTA684 is just a session identifier. The code continues
to run, though, and I can interact with the menus, but there must be
something else on one of the deeper menus because when I get to a
certain menu I get this undefined terminal message "-SMG-F-UNDTERNOP,
undefined terminal - couldn't access private terminal table" (see
farther below for the whole thing).

I wondered if anyone has any ideas for how to proceed.

--Dale--

/**
* socket.TelnetIO - a telnet implementation
* --
* $Id: TelnetIO.java,v 1.10 1998/02/09 10:22:18 leo Exp $
* $timestamp: Tue May 27 13:27:05 1997 by Matthias L. Jugel :$
*
* This file is part of "The Java Telnet Applet".
*
* This is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published
by
* the Free Software Foundation; either version 2, or (at your option)
* any later version.
*
* "The Java Telnet Applet" is distributed in the hope that it will be
* useful, but WITHOUT ANY WARRANTY; without even the implied warranty
of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this software; see the file COPYING. If not, write to
the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/


Here's the underfined terminal message, referenced above:

-SMG-F-UNDTERNOP, undefined terminal - couldn't access private
terminal table
%TRACE-F-TRACEBACK, symbolic stack dump follows
image module routine line rel PC
abs PC
DEC$COBRTL 0 000000000003A44C
000000007C1B444C
DEC$COBRTL 0 000000000003A170
000000007C1B4170
DEC$COBRTL 0 0000000000029910
000000007C1A3910
DEC$COBRTL 0 00000000000006B0
000000007C17A6B0

TelnetIO.receive(): read bytes: 453
TelnetIO.negotiate([B@93dcd,453)

FOCUSFUNCTION 0 0000000000FBC080
0000000000FCC080
FOCUSFUNCTION 0 0000000000FBC654
0000000000FCC654
PTHREAD$RTL 0 00000000000312FC
000000007BB9F2FC
PTHREAD$RTL 0 0000000000012B48
000000007BB80B48
0 FFFFFFFF8A72D3F4
FFFFFFFF8A72D3F4

 

[Chris Lamprecht]

Check out Jakarta commons/net:
http://jakarta.apache.org/commons/net/index.html

 

[Dale]

Chris, Thanks! Your pointer helped me get around the "-SET-I-UNKTERM,
unknown terminal type" and other similar issues (I'm just using the
rlogin example from the commons net utility package, as you
suggested).

All, There's one more thing that I would like to conquer... handling
of control characters.

What looks to me like this:

22-Aug-03 03:42 PM AAXXXXX
MENUOP
O R D E R P R O C E S S I N G
29 BULK(snip)
Comes back like this:

?[22;42H0?[22;43H1?[22;42H?[4;3H?[1;19H?[1;69H MENUOP?[2;5H?[7m
?[m?[2;1H?[2;9
H?[7mR?[m?[2;1H?[2;11H?[7mD?[m?[2;1H?[2;13H?[7mE?[m?[2;1H?[2;15H?[7mR?[m?[2;1H?[
2;17H?[7m P R O C E S?[m?[2;1H?[2;30H?[7mS I N G ?[m?[3;1H?[3;5H?[7m
?[m?[3;1H?[
3;9H?[7mR?[m?[3;1H?[3;11H?[7mD?[m?[3;1H?[3;13H?[7mE?[m?[3;1H?[3;15H?[7mR?[m?[3;1
H?[3;17H?[7m P R O C E S?[m?[3;1H?[3;30H?[7mS I N G ?[m?[4;1H?[4;41H29
BULK(snip)

The part of the page 'O R D E R P R O C E S S I N G' is in big
letters and is reverse highlighted, and double high characters (on my
PowerTerm emulator). And obviously some of the stuff on the screen is
written in a different order and/or is retained from the previous
menu, but I didn't expect to completely "loose" the "O" from "O R D E
R" for instance.

So I guess what I'm wondering is if there's some kind of "virtual
screen" that someone has come-up with.

Thanks.

 

[Chris Lamprecht]

Dale,
Those appear to be VT100 or ANSI-type terminal escape codes. I'm not
sure if Jakarta net can do anything with those. If not, you'll have to find
one or write something yourself that basically strips them out (unless you
want to display it, but I think you said you were just screen scraping).
The basic format of the control codes is something like "?[2;1H", where the
"?" is some non-displayable code. In ANSI it's ASCII code 27 (sometimes
displays as a little left arrow). It might be the same in VT100, I'm not
sure (Try google, it knows all). I'm going to have to write almost the
exact same thing (a scraper) soon; I'd appreciate any code you can share
with me (I haven't actually used Jakarta Commons/net yet).

-Chris

 

[Dale]

Chris,

Considering you may go down this path, I'll state my findings to date,
and you can use (and correct/enhance).

de.mud.jta (http://javassh.org):
This package is open source. It has a vt320 class that one could
theoretically use to handle terminal control codes (you talk to the
vt320 instead of directly to the telnet session). I have not been
able to get the examples to work with my telnet host. The package is
extensive (and complicated). I've asked a question on the source
forge forum to get assistance in where and how one might wire-in a way
to drive a telnet application (screen scrape).

com.jscape.inet.telnet (http://www.jscape.com):
This package is not open source, and it costs a lot (for the tiny part
I want). It craps-out after 30 days. It has a class specifically
designed for screen scraping (TelnetScript). Using the example
TelnetScript partially works against my telnet host (I get connected
and can do some menus, but I get errors about not handling my terminal
type, which is a show stopper).

org.apache.commons.net.telnet
(http://http://jakarta.apache.org/commons/net/index.html):
This package is open source. This seems to have no 'terminal'
classes, which means the control codes look pretty messy. I was able
to talk to my telnet host without terminal type errors, but later lost
the ability to talk at all (maybe a firewall issue). The example just
starts up input and output streams, so is not helpful to suggest how
to handle screen scraping. I wrote something, but need to get the
firewall thing fixed to test.

socket (http://www.first.fraunhofer.de/persons/leo/java/Telnet/)
This package is open source, but not supported. This appears to be a
pre-cursor to the de.mud.jta package. This package, though, has a
class called TelnetWrapper, and a method called receiveUntil that made
interacting in screen scrape mode very easy. But when I use the
TelnetWrapper directly, I get the terminal type error on certain
menus, and the host program bombs. The TelnetWrapper and receiveUntil
seem not to be included in the current de.mud package.

--Dale--

Dale,
Those appear to be VT100 or ANSI-type terminal escape codes. I'm not
sure if Jakarta net can do anything with those. If not, you'll have to find
one or write something yourself that basically strips them out (unless you
want to display it, but I think you said you were just screen scraping).
The basic format of the control codes is something like "?[2;1H", where the
"?" is some non-displayable code. In ANSI it's ASCII code 27 (sometimes
displays as a little left arrow). It might be the same in VT100, I'm not
sure (Try google, it knows all). I'm going to have to write almost the
exact same thing (a scraper) soon; I'd appreciate any code you can share
with me (I haven't actually used Jakarta Commons/net yet).

-Chris

All, There's one more thing that I would like to conquer... handling
of control characters. (snip)
So I guess what I'm wondering is if there's some kind of "virtual
screen" that someone has come-up with.