Re: CSI DECSED and ED

[Bryan Christ]

Thomas,

Thank you.  As always I appreciate your expert feedback on this.

On Mon, Aug 5, 2019 at 6:10 PM Thomas Dickey <address@hidden> wrote:

On Mon, Aug 05, 2019 at 04:59:30PM -0500, Bryan Christ wrote:
> Can anyone tell me what the correct behavior for this CSI when the cursor
> is in the middle of the row (let's say col 20 for example) and the modifier
> (Ps) is "1"... The xterm documentation says "Selective Erase Above".  I am
> currently coding my emulator so that the first part of the current row
> (everything left of the cursor) is cleared and all the lines above it.
> That seems to be the behavior that "vttest" expects but am looking for
> clarification.  If so, then does the opposite apply for modifier 0?  (in
> another words, everything to the right and below?)

CSI ? Ps J
          Erase in Display (DECSED), VT220.
            Ps = 0  -> Selective Erase Below (default).
            Ps = 1  -> Selective Erase Above.
            Ps = 2  -> Selective Erase All.
            Ps = 3  -> Selective Erase Saved Lines (xterm).

Something like that: the cell where the cursor is will also be cleared.
So it's not strictly opposite since the two actions overlap.

--
Thomas E. Dickey <address@hidden>
https://invisible-island.net
ftp://ftp.invisible-island.net

--

Bryan
<><