RE: [LINUX5250] I need help with Selection Field processing

[James Rich <james@xxxxxxxxxxx>]

On Thu, 14 Apr 2005, Ruel, Marc-Antoine wrote:

> I tried to read this but it gives me nausea. :) Did you advance in your 
> research?

I finally have some interesting results.  Running a sniffer revealed that 
iSeries Access sends the following to the iSeries when pressing enter on 
the first menu seletion (on my particular test screen):

12 a0 00 00 04 00 80 03 01 03 f1 ff ef

but tn5250 sends:

12 a0 00 00 04 00 00 03 01 03 f1 ff ef

the difference is the second byte after the hex 04 (the length of the 
variable portion of the header).  According to the RFC, this should always 
be 00, i.e. the way tn5250 does it.  Why iSeries Access does it 
differently is unclear, but changing tn5250 to always send 0x80 causes it 
to terminate unexpectedly.  So far I can't find any docs to tell me what 
the 0x80 might mean or under what conditions to send it.  The RFC I'm 
looking at is:

http://www.faqs.org/rfcs/rfc1205.html

Specifically in section 3. Data Stream Format.

If anyone has any clues I'd love to hear from you.

James Rich

It's not the software that's free; it's you.
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