ed(1) as default editor in sh(1)

[<tlaronde%kergis.com@localhost>]

In commit 684f0c282018583d8983ab6b3218c03da6841159, uwe writes:

	TBH, I was a bit incredulous, but sh's own fc _does_ use ed if EDITOR
    	is not set, though it seems to be the only program in base to do
	this.  Speak of a self-fulfilling prophecy...

IMHO, sh(1) is right here. Ed(1) is the only _line_ editor. Others
require 2D interface (even if only with curses; that's 2D
nonetheless).

Sh(1) has to be useful in case of disaster and very limited (line
interaction) connection means. Ed(1) is the only vital editor. The
variable can be defined to suit the user needs, via the
configuration files so the default can be overwritten.

ed(1) is in bin/. (external) nvi(1) is in usr.bin/. And this is logical.
(Even if vi is added to rescue; but you have to have a terminal
behaving correctly for curses (or the reverse), and there are bugs in
vi(1).)

So, IMHO, the default, in code, should stay with ed(1). The question
would be whether other utilities have the wrong default (depending on
whether they are considered crucial enough to get things running)...
-- 
        Thierry Laronde <tlaronde +AT+ kergis +dot+ com>
                     http://www.kergis.com/
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