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From: jv@mhres.mh.nl (Johan Vromans)
Newsgroups: comp.unix.wizards
Subject: Re: Ksh cursor keys (Was: who uses which shells)
Message-ID: <1899@mhres.mh.nl>
Date: 2 Jun 88 09:04:18 GMT
References: <284@marob.MASA.COM>
Organization: Multihouse NV, the Netherlands
Lines: 22

From article <284@marob.MASA.COM>, by daveh@marob.MASA.COM (Dave Hammond):
> In article <1887@mhres.mh.nl> jv@mhres.mh.nl (Johan Vromans) writes:
>>But WHY does ksh not allow cursor (=arrow) keys to be used?
> 
> Ksh does not make use of any terminal-independent characteristics, such as
> cursor-keys. External editors are emulated using only newlines, returns
> and spaces to modify the edit line. 

This is oversimplification. About 50 vi and emacs editing commands are 
emulated.

>                                     Making use of cursor-keys also requires
> parsing multiple character sequences which would add some overhead.

Sequences like ESC-d (delete-word), ESC-f (forward-word) etc. are
handled, as are ESC-* (filename generation) and ESC-= (file list).
Adding some overhead to break the misnotion that Unix is user-unfriendly
pays.
-- 
Johan Vromans                              | jv@mh.nl via European backbone
Multihouse N.V., Gouda, the Netherlands    | uucp: ..{uunet!}mcvax!mh.nl!jv
"It is better to light a candle than to curse the darkness"