Richard ponders:
: Since I've used the 3k since 1983 and never used Line Modify or Modify
: All, *except* to fix people's terminals at times when they hit the
: wrong f-key and turned them on and I'm at least a little more curious
: than the average user, I just *know* many of us in the 3k community are
: waiting for someone to explain just what these things were for!

I went for at least ten years of staring at the LINE MODIFY key (or
function key label) on HP terminals thinking "Oh, that's some block
mode thing" when in fact LINE MODIFY mode is designed *specifically*
for use in character mode / command line programs like the CI, Basic,
Query, or any other program which interactively displays a prompt at
the terminal to which the user types a response.

Your terminal (or terminal emulator) has been working hard keeping
track of which characters on each input line were typed by you and
which were part of the prompt that came from the system for every
command line you've ever typed on a 3000, in the faint hope that one
day you might actualy want to avail yourself of the wonderful LINE
MODIFY feature.

Let us hark back to December 28th, 1998, the last time this question
came up...

Paul writes:
: I thought perhaps the reason for having a colon on a command might be
: that those of us who can remember the days before there was a redo
: command, found out that you could reuse a command (or fix it up),
: by placing the cursor at a previous line on the screen and hitting enter.
:
: The command of course, has the colon at the front of it, and you have to
: remember to delete that or it gets transmitted.

Ah, but there's this magic function key on your terminal (under MODES)
labeled "LINE MODIFY", which many people don't know how to use.

After typing a command and having it get an error, simply press LINE MODIFY,
then move the cursor up and make any changes you like to the command line,
using all of the terminal editing features (insert/delete char, etc.).  Then
simply press the <RETURN> key.  The command is retransmitted, none of the
keys you pressed while editing are transmitted, LINE MODIFY mode is exited,
and magically the prompt is *not* transmitted.

HP terminals *remember* which characters on each line make up the prompt
and which were typed in response by the user, so that LINE MODIFY mode
can work.

Cool, huh?

G.