12 Aug
2001
12 Aug
'01
8:01 p.m.
Paul Williams skrev:
Iggy Drougge wrote:
>
> Paul Williams skrev:
> >
> >F11 only generates raw ESC in VT100 mode, which has other drawbacks.
>
> What was DEC's logic behind the exclusion of a proper escape key?
I'm not sure what you mean by "proper"
escape key. If you would like a
key that sends a code that is interpreted by applications as meaning
"cancel" or "exit insert mode", that is fine. However, this key
shouldn't send the control code ESC and expect the application to do
something with this code alone. That usage should have been considered
obsolete by the first issue of ASCII in 1963. ESC alters the meanings of
a certain number of following characters.
I would think that DEC's exclusion of a key that
sends ESC alone was a
consequence of placing a number of function keys on the keyboard. If you
put a keys "F1" to "F20" or "Select" or "Help" on
the keyboard, you
quickly run out of 7-bit codes that they could send. Using ESC as an
introducer gives you an extensible system, in the spirit of ANSI X3.64.
(I know X3.64 doesn't define keyboard codes, but the mechanism is
identical).
IOW, historical reasons. =)
Mind you, DEC terminals are the only remotely modern systems which I've used
lacking a key marked ESC(ape) which does something useful with vi.
--
En ligne avec Thor 2.6a.
Amiga: (noun) The most technologically advanced computer that hardly anyone
cares about.
Use in sentence: "I wanted to buy an Amiga for its low price and great color
graphics, but everyone else seems to be using IBMs or Macintoshes. So, to
remain compatible with the rest of the world, I spent three times as much on a
Macintosh and got only half the graphics capability of an Amiga."