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

[Johnny Billquist]

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the screen are no longer active, and can't be overwritten, so they stay 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