In <[EMAIL PROTECTED]>, on
10/18/2005
at 08:43 AM, "McKown, John" <[EMAIL PROTECTED]> said:
>You mean you want more than two different screen sizes? That is not
>particularily a TSO restriction, it is a 3270 data stream
>restriction.
No it isn't.
>A 3270 can only have two different screen sized, based on the 3270
>architecture.
Untrue, and has been for decades.
>In order to have "n" different screen sizes would be a horrendous
>challange to TSO and VTAM as well.
No.
>First, IBM would need to implement a new "write" command (WRITE/ERASE
>SELECT SIZE or something like that).
BTDTGTTS. It's called WSF.
>But then they'd need to update the defination of LU type 2 in VTAM
>to handle "n" possible screen sizes.
No. VTAM has had the required support for decades.
>Now TSO must keep track of the various
>possible screen sizes and select the "most appropriate" one.
Why? That's an application function, unless you're running SM. TSO
just has to pass on the data stream, which it already has the code to
do.
>Oh, the TN3270E defination and emulators would need to be updated to
>support this as well.
No. The old ones would continue to work.
>And always remember that the 3270 data stream does __NOT__ tell how
>to position the current write location using x,y coordinates.
An application that switches geometry is responsible for keeping track
of what it did. That was true as far back as the 3278-5.
>This would be very expensive for a "dying" technology.
No. The existing VTAM and VTIOC code are fine as they are; you only
need new TSO code if you want Session Manager to support variable
geometry. The major change would be in ISPF, to generalize the
existing 3290 support.
>If it were me, I'd be looking at something to totally replace TSO.
>Oh, wait, that is WSED
No it isn't.
--
Shmuel (Seymour J.) Metz, SysProg and JOAT
ISO position; see <http://patriot.net/~shmuel/resume/brief.html>
We don't care. We don't have to care, we're Congress.
(S877: The Shut up and Eat Your spam act of 2003)
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