Most (all I've seen) Windows keyboards have a "break" key; I have to say
I've never used it or ever seen anyone use it. It's up there beside "scroll
lock" and "print screen/sysRq" (maybe more obscure, although I think that
applications and/or DOS support some screen printing or capture capability).

The most common way to interrupt a running operation is to present a dialog
on the screen which shows a progress bar and a cancel button. You click the
cancel button, and it stops the operation.

Occasionally the ESC key is used as an interrupt (complicating things a bit
further).

I have never seen a Windows application that uses a keyboard combination to
act as a halt command unless it was written in Smalltalk (my experience is
limited, however :-) On the Mac, Command-. is almost always used in
conjunction with this type of dialog; it is not a generic interrupt
capability. Ctrl-Alt-Del on the PC and Command-Shift-ESC on the Mac are
notable exceptions.

It is quite bad when someone expects to copy text and a debugger window
appears on the screen.

One of the reasons I like Smalltalk is that there are few hard limits, and
where they do exist, they are buried in sugar to make it look like they are
not really there.

This is reflected in the "interruptability/inspectability" of the system,
and you see the same concept arise when you accidentally middle-click on a
Morphic window and the damn halos pop up. Fine if you want to use them, very
confusing if you have no idea what you just did.

I suggest that the "interruptability/inspectability" of Smalltalk/Squeak be
tempered on a "need to know" basis. If you want to step in and look at
things, there should be no barriers to doing so, but the system should
protect people from "accidentally" wandering into a space that is totally
irrelevant to where they were trying to go.

Maybe a simple solution is to add something to the preferences that toggles
between "I am a Developer" and "I am Curious, but not too Curious".

Steve

> -----Original Message-----
> From: Jesse Welton [mailto:jwelton at pacific.mps.ohio-state.edu]
> Sent: May 19, 1999 7:06 AM
> To: squeak at cs.uiuc.edu
> Subject: Re: Ctrl, Alt and Menu keys (was: RE: Thinking about a better
> UI)
>
>
> Dino wrote:
> >
> > Doesn't ctrl-c sound a whole lot more like cancel than command-.?
>
> Sure, but it's no less arbitrary.  That c could just as well stand for
> "cut", "copy", "close", "clear", "color", etc.  Even as "cancel" it
> could have the sense of "undo last changes".  The operation you have
> in mind could also be called "interrupt", "halt", or "stop", all of
> which I think are relatively well suggested by a period, and certainly
> not by ctrl-c.  Personally, I usually think of the operation as an
> interruption of the operation or (in a less technical mood) just "hey,
> stop that!"  All of which is not to say that I think ctrl-c for
> "cancel" is ill-chosen, just that command-. is every bit as sensible,
> and quite possibly more so since it connects more to the operation
> than the word you use for the operation.
>
> -Jesse Welton
>