Since tn5250 uses ncurses for the interface, one possibility might be to
use Expect to automate the ncurses interface.

I would think that would definitely be simpler than programming to the
5250 data stream, or (maybe) simpler than lib5250.

Expect doesn't natively do ncurses, but a Google search on "expect
ncurses" indicates there are ways to do it (but I haven't done it myself).


Richard Nolde wrote:
Original message:
TN5250 list members:

I've been tasked with writing an interface between an application that
runs on a remote iSeries host, accessible with TN5250 over a private
network, and our application that would query the iSeries in real time
without human interaction. My application will run on a Linux or AIX
box, and act like a broker between the local application and the remote
iSeries host application that contains the database we are querying.

Richard Nolde


message: 2
date: Thu, 15 Jul 2010 18:10:08 -0600
from: Xavier S?nchez<antoniobarquero@xxxxxxxxx>

It seems like what you want to know are details about the 5250 data stream.

5250 is a data stream that contains not only plain text data, but attributes
for the data displayed on the screen (like foreground color, background
color, underlining and bold), along with keyboard command attention (CA) and
command function (CF) keys.

Yes, I've studied enough of the source code to the tn5250 application to
see that it is a highly complex protocol with a multitude of control
sequences and status bits and very demanding sequencing requirements.
I think the best source of that complete information is specified in a set
of books by IBM, like "SNA Formats", and others related to the SNA data
streams used in 5250-like terminals.

There is an on-line source of information where you will probably find it.

I'd suggest you search the IBM search engine at this URL. You will have to
look for further to find what you need. Try to find out one version that
deals with iSeries under the same bookmanager library reader.

Good luck!

Thanks for the link. As with most things IBM, it is harder to find with
there own search engine that with Google, but your link saved me a lot
of time.
X Sanchez

-----Mensaje original-----
De: linux5250-bounces@xxxxxxxxxxxx [mailto:linux5250-bounces@xxxxxxxxxxxx]
En nombre de Richard Nolde
Enviado el: Jueves, 15 de Julio de 2010 04:47 p.m.
Para: linux5250@xxxxxxxxxxxx
Asunto: [LINUX5250] Driving TN5250 non-interactively

from: Jim Oberholtzer <midrangel@xxxxxxxxxx>

subject: Re: [LINUX5250] Driving TN5250 non-interactively

You say that the iSeries is on a private LAN. Why not just write a
program using ODBC to access the data you are after? Or, create some
stored procedures on the iSeries and use a web service over there. I
wonder if the direction is coming from someone that does not realize
those facilities are available on that machine, or alternatively you
don't have the ability to sign on and create things there. If the goal
is to run specific commands, you might consider an FTP script using

We do not have any access to the remote AS400 machine except to run this one specific application. The business partner with the AS400 does not have its own developers and the administrative staff is scared to change anything. We looked into developing a web service on their end and they have no development environment or programming staff. None of our IT staff has ever worked on an AS400. We do only Linux/AIX and database applications that interface with our own servers so we are stuck with this kind of interface.

That said creating a screen scraper application really is all about
knowing the 5250 data stream.

Try this for more understanding. I pulled it from V5R3 since you said
"iSeries" guessing that the system might be a bit further back in OS
than current.

I don't even know the exact hardware or version of the OS they are running but I can be relatively sure it isn't current. Thanks for the link.

Jim Oberholtzer
CEO/Chief Technical Architect
Agile Technology Architects, LLC

message: 4
date: Fri, 16 Jul 2010 10:29:23 -0400
from: "Raul A. Jager W."<raul@xxxxxxxxxx>
subject: Re: [LINUX5250] Driving TN5250 non-interactively

Can you use a web service instead?

If the reports to be transfered are easy to build, you can generate a
web page and retrieve it automaticlay.
If you need the output of a "batch" program, you can run it from a web
page (automaticaly, by using something like wget) and retrive the spool
file after.

See above. Our only option is to use the existing interface at this point. I think it is going to be a long shot at best, with lots of potential for hangups, but we have to prove whether it is practical or not.

Richard Nolde

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