[Info-vax] macOS Terminal app. Numeric keypad fails for EDT.

[alanfe...@gmail.com]

On Saturday, September 24, 2022 at 11:38:53 AM UTC-4, Johnny Billquist wrote:
> On 2022-09-24 05:13, alanfe... at gmail.com wrote: 
> > On Friday, September 23, 2022 at 4:34:55 PM UTC-4, Johnny Billquist wrote: 
> >> On 2022-09-23 21:16, Michael Moroney wrote: 
> >>> On 9/22/2022 5:06 PM, alanfe... at gmail.com wrote: 
> >>>> The only problem I have with Terminal is that using EDT in full-screen 
> >>>> mode wipes out part of the history buffer (not the commands, but 
> >>>> screen output). 
> >>> 
> >>> I noticed something like that with iterm2, not elsewhere, I'll look at 
> >>> EDT to see what's up. 
> >> Not sure what you are referring to. EDT clears the screen in order to 
> >> draw whatever it wants to show there. So of course, whatever else was 
> >> there before is gone. 
> >> 
> >> Or are you referring to something else? 
> >> 
> >> Johnny 
> > 
> > Say I run SHOW SYSTEM on EISNER. It's like a hundred-something lines. Say it's 160 lines. I run EDT. It clears the screen, brings up the file, I do my edits, and exit. Now I page-up to review the SHOW SYSTEM output, and the l last 30 or 40 or whatever lines are gone. If I had instead run, say, SH DEV DS, I get what,10 lines of output? Then I do a full-screen editing session. Then I page-up to see the SH DEV DS output again, and it's gone. Older stuff is still there, but the last n lines of what was there before I edited something is gone for good. Maybe you never do the page-up bit to see previous commands and their outputs.
> The last 30-40 lines (the screen size I would guess) would be gone, 
> since those lines were reused by EDT. Anything that was off the top of 
> the screen are no longer active, and can't be overwritten, so they stay 
> around. 
> 
> On newer terminal emulators, there exists an escape sequence to switch 
> to an alternative window, which some applications use, so that all 
> current screen content remains. I highly doubt EDT knows about, or uses 
> that escape sequence. But I have a feeling that is what you are thinking 
> of/hoping for. Some other, newer editors, would be using that when possible. 
> 
> A real VT terminal do not have that alternative window, so it's 
> something that DEC never played with. 
> 
> Johnny

Yep, it works fine with TPU. One then needs to put it in a DCL jacket with the right secret escape sequence, or get one of these newfangled terminal emulators.