[comp.unix.questions] Botched typeahead

campbell@maynard.UUCP (04/05/87)

In article <8703231450.AA18626@ephemeral.ai.toronto.edu> lamy@ai.toronto.edu writes:
>
>                  ... Scream as you like against VMS, it does typeahead
>   the way it ought to be done (i.e. the way I like it :-)

I agree completely.  UNIX echoes typeahead incorrectly.  The correct way,
as implemented by TOPS-20 and VMS, is to echo typed input when a program
reads it, not when it's typed.

I really like most aspects of UNIX, but this is one case where VMS (and
TOPS-20) clearly win.  How about it, AT&T, can this be fixed in SVR4?
-- 
Larry Campbell                                The Boston Software Works, Inc.
Internet: campbell@maynard.BSW.COM          120 Fulton Street, Boston MA 02109
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chris@mimsy.UUCP (04/09/87)

In article <891@maynard.BSW.COM> campbell@maynard.BSW.COM (Larry
Campbell) writes:
>I agree completely.  UNIX echoes typeahead incorrectly.  The correct way,
>as implemented by TOPS-20 and VMS, is to echo typed input when a program
>reads it, not when it's typed.

This seems to be a matter of taste.  On a fast system, I like deferred
(VMS-style) echo.  On a slow system, I like immediate echo.  I want
both, so how about an `stty' option?

(99 blocks of crud in the kernel, 99 blocks of crud.  Put in a patch,
compile again, 100 blocks of crud in the kernel!  :-) )
-- 
In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 7690)
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gwyn@brl-smoke.ARPA (Doug Gwyn ) (04/09/87)

If anyone plans to implement deferred echo of type-ahead, please
be sure to include the ability to force an echo of what one has
typed ahead before it gets read.  The DEC-style ^R (reprint input)
found on systems like 4.nBSD seems ideal for this.

paul@vixie.UUCP (04/11/87)

In article <5737@brl-smoke.ARPA> gwyn@brl.arpa (Doug Gwyn) writes:
#If anyone plans to implement deferred echo of type-ahead, please
#be sure to include the ability to force an echo of what one has
#typed ahead before it gets read.  The DEC-style ^R (reprint input)
#found on systems like 4.nBSD seems ideal for this.

As long as we're on the subject, how about a seperate character to
eliminate your whole typeahead buffer -- newlines and all?  VMS uses
^X for this, ^U for line-delete, and ^X is like ^U if you are typing
to a read request -- i.e., you are not experiencing delayed echo.

In reference to the above, if delayed echo is implemented, ^R should
reprint the entire buffer -- not just the last line -- whenever echo
is being delayed.  I remember this from the Alpha Micro, and I miss it.
-- 
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