> -----Original Message----- > From: IBM Mainframe Discussion List > [mailto:[EMAIL PROTECTED] On Behalf Of Howard Brazee > Sent: Tuesday, October 18, 2005 8:12 AM > To: IBM-MAIN@BAMA.UA.EDU > Subject: Re: TN3270 Emulator > > > I wish IBM would upgrade TSO/ISPF so that it didn't assume one of its > old terminals. An improved virtual terminal could be designed that > could switch between 80, 133 or even 250 columns wide while editing a > file, for instance. >
You mean you want more than two different screen sizes? That is not particularily a TSO restriction, it is a 3270 data stream restriction. A 3270 can only have two different screen sized, based on the 3270 architecture. There is the "normal" size (usually, but not necessarily 24x80) which is "switched to" with the ERASE/WRITE command. There is the "alternate" size (whatever is specified in the emulator/VTAM BIND image) which is "switched to" with the ERASE/WRITE ALTERNATE command. In order to have "n" different screen sizes would be a horrendous challange to TSO and VTAM as well. First, IBM would need to implement a new "write" command (WRITE/ERASE SELECT SIZE or something like that). But then they'd need to update the defination of LU type 2 in VTAM to handle "n" possible screen sizes. Now TSO must keep track of the various possible screen sizes and select the "most appropriate" one. Oh, the TN3270E defination and emulators would need to be updated to support this as well. And always remember that the 3270 data stream does __NOT__ tell how to position the current write location using x,y coordinates. It uses "buffer addresses" which are basically "number of bytes from the beginning of the screen image". The TN3270E emulator converts whese to actual x,y positions on the screen. This would be very expensive for a "dying" technology. If it were me, I'd be looking at something to totally replace TSO. Oh, wait, that is WSED (or whatever it is called now). -- John McKown Senior Systems Programmer UICI Insurance Center Information Technology This message (including any attachments) contains confidential information intended for a specific individual and purpose, and its' content is protected by law. If you are not the intended recipient, you should delete this message and are hereby notified that any disclosure, copying, or distribution of this transmission, or taking any action based on it, is strictly prohibited. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
