[Info-vax] escape sequences, cursor positioning

[David J Dachtera]

JF Mezei wrote:
> 
> Richard B. Gilbert wrote:
> 
> > I don't believe it's possible and even if it can be done, I doubt if the
> > result could possibly be worth the effort required.
> >
> 
> Say the field is 30 characters long. You set character attribute to
> underscore, then write 30 spaces, then send an escape sequence to go
> back 30 spaces. This is your prompt.  After the prompt completes you
> press return, you first send an escape sequence to turn off the
> underscore attribute.
> 
> This is not perfect though. If you do a delete-character while editing,
> the underscored field becomes 29 bytes long.
> 
> So this is an approximation of what would be done by FMS for instance.

Following up on the suggestion to set the terminal (program) to display
control characters rather than interpret them, I find myself
wondering...

1. Set the video attributes for an area of the display to underscore
whatever characters are there. (Begin underscore, send spaces, end
underscore.)

2. Use escape sequences to position the cursor into that area as part of
a /PROMPT string.

Will characters typed there be underscored?

Been a while since I played with that sort of stuff, but I seem to
recall All-In-One doing some of that via FMS.

So, JF - you still use A1 right? If you bring up such a form, then
switch your terminal (program) to display controls rather than interpret
them, what do you see? Do you see just the characters echoed, or are
they surrounded by the begin/end underscore sequences, respectively?

D.J.D.