Unix deficiencies/problems (immediate character echoing)

Usenet file owner usenet at cps3xx.UUCP
Thu May 11 03:34:31 AEST 1989


In article <8907 at csli.Stanford.EDU> gandalf at csli.stanford.edu (Juergen Wagner) writes:
>In article <2914 at cps3xx.UUCP> rang at cpsin3.cps.msu.edu (Anton Rang) writes:
>>...
>>  Does anyone know the original reason for the immediate echoing?
>>...
>
>The question which has to be raised is who echoes the characters as they
>are typed. Is it the driver which is in some echo mode, or is it the
>application (shell, emacs, whatever)?
>
> [...]
>
>The alternative would be to require the application to echo characters just
>as it reads them (this would give you the desired behaviour).

  Umm, to display my ignorance of UNIX device driver internals, why
can't it be done like this?

  1.  User types character.  Driver puts it in some queue.
  2.  Application wants character.  Calls [ something ] to get it from queue.
      [ something ] echoes it.

After all, applications don't directly grab characters; if they're
going through some common point, you could do echoing there.  (Right?)

+---------------------------+------------------------+-------------------+
| Anton Rang (grad student) | "VMS Forever!"         | VOTE on	         |
| Michigan State University | rang at cpswh.cps.msu.edu | rec.music.newage! |
+---------------------------+------------------------+-------------------+
| Send votes for/against rec.music.newage to "rang at cpswh.cps.msu.edu".   |
+---------------------------+------------------------+-------------------+



More information about the Comp.unix.questions mailing list