Where Goeth the Line-editing? (was Re: Strangeness in shell)

[Jonathan I. Kamens]

  A good place to look for an example of one way to have a uniform
line-editing interface is in Multics (Multics people correct me if I'm
wrong, because I'm writing this second-hand -- I never even got to
login to MIT Multics before it went away :-().

  In multics, it was possible to install a driver that lived at the
gateway between the actual terminal and user processes.  This driver
would intercept and process *all* input before sending it to the
process.  Therefore, if you wrote a line-editing driver and installed
it, it would work for *every* program on the system, without fail.
There were, of course, ways to turn off the line-editing features for
programs that needed character-by-character input.

  So Multics did what several people have been suggesting -- make the
terminal editing capabilities separate both from the program and the
actual terminal by putting it in a driver that can be modified or
replaced by the user.

  Wouldn't it be great if you could use line-editing in ed?  History
substitution?  Wouldn't it be great if all of the shells used the same
characters and commands for history substitution and command-line
editing?  You get the idea....

Jonathan Kamens			              USnail:
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