[net.unix-wizards] vt100 insert and delete line

ccdan@UCB-VAX.ARPA@ucdavis.UUCP (06/14/84)

From:  System Manager <ucdavis!ccdan@UCB-VAX.ARPA>

i thought that insert and delete line was standard on
vt100 (and vt100 compatible terminals.)  i use VMS
occasionally, and EDT (the screen editor) uses the
insert/delete line functions on vt100 terminals.  i
happen to only have vt100-compatible terminals within
reach at the moment, but they all respond to the
insert/delete line codes.  just so you know, the
ANSI sequence for insert line is "^[[pL", (that's:
escape, left bracket, number, capital L, no quotes)
where p is the number of lines to be inserted, in
numeric form.  if no number is specified, 1 is the
default.  delete line is "^[[pM", with the same syntax.

i have noted that none of the termcap files i've
ever seen from berkeley have had these sequences
in them; i've always had to add them.  (:al=: and
:dl=: capabilities)  i know we have local users who
use real, live, DEC vt100s, and none have complained.
i'd suggest you try the sequences and see if they
work on your terminals.  all this effort to change
the scrolling region may not be necessary.

--dan dorough, uc davis, computer center, davis, ca.
               ucbvax!ucdavis!ccdan  (415) 752-0235

guy@rlgvax.UUCP (06/16/84)

> i thought that insert and delete line was standard on
> vt100 (and vt100 compatible terminals.)

It isn't.  My terminal is a VT100 (made by DEC - or, if it isn't, I can
get the manufacturer into a hell of a lot of trademark trouble) and it has
no such feature.

It exists on some VT100-family terminals from DEC (but not the VT100), it
probably exists on some VT100-compatible terminals, and it exists on VT100s
with the printer port option.

I suspect your EDT knows that it's not running on a vanilla VT100.  There is
an "edit mode" flag, settable with the SET TERMINAL command and gettable,
at least, with some QIO function, which says that the terminal supports the
ANSI standard insert/delete line/character functions.  It probably looks at
that.  Either your VT100s are non-standard and it is sending those sequences,
or they are standard, that flag isn't set, and EDT sees that fact and doesn't
use insert/delete line.

	Guy Harris
	{seismo,ihnp4,allegra}!rlgvax!guy

barmar@mit-eddie.UUCP (06/16/84)

You must be looking at VT102's or VT132's.  VT100's most definitely DO
NOT have insert/delete lines, just scroll regions.
-- 
			Barry Margolin
			ARPA: barmar@MIT-Multics
			UUCP: ..!genrad!mit-eddie!barmar