echoing style - DOS,VMS vs. Unix (was: AT&T Joining OSF)

[Greg Woods]

In article <397 at nynex1.UUCP> curt at chaos.UUCP (Curtis Villamizar) writes:
> The real advantage of delaying echo is input gets put on the screen where
> it belongs, not where the cursor happened to be when the character was typed.
> This is a plus for "cooked" mode applications which use cursor movement.

This can be up to the application if desired.  All that is required is
that the application set noecho, and echo when it actually reads input.
You certianly don't have to be in raw or cbreak mode for this to work.

If you can't write a fix for the line discipline, why not write a simple
front-end for the shell that does the above?  (I know, it won't fix
echoing anywhere else, but I find I usually typeahead only in the shell
(or an editor which is doing it's own echoing anyway!).)

> The "new tty" line dicipline on my Sun which I presume either Berkley or Sun
> did is an example of an alternate line dicipline.  When I go back to Sys V,

The 4th BSD tty(4) man page from May 19, 1986 describes new tty.

> I am always annoyed when it backspaces over my prompt and does other stupid
> things.  This kind of code gets put in the line dicipline once, and can be
> used with any device driver (including pty's).

Does anyone know if the newtty line discipline is ALL Berkeley code?
Except for the job control features, it shouldn't be too hard to graft
it into termio.

> I think this would be done in a streams layer on Sys V.3 but I'm not sure.
> Does anyone know if line diciplines are obsolete and replaced by streams stuff?

There is usually a STREAMS module that does the same job as a line
discipline (called "CANONPROC" in the "Streams Primer").

In Release 3.0, STREAMS isn't used by the tty drivers in general.  I
understand that in Release 3.1, tty's may be STREAMS based, but aren't
necessarily so.

With Release 3.1 for the 3B computers, there are three line disciplines
supplied.  One for tty's, one for xt's, and one for sxt's.  I'm not sure
of the differences, though I only skimmed the driver manual, so I may
have missed the descriptions.  The Release 3.1 termio(7) page should
describe them, unless they've been given their own pages :-).

One thing about STREAMS that bugs me is that the raw drivers must be
re-written.  It's necessary, but annoying.  I wonder if you could write
a STREAMS module that faked itself as a process so that it could call
an old-style driver....

CALL FOR CODE:  If anyone has written any STREAMS drivers or modules,
and would be willing to post them, please do (in the appropriate
newsgroup).  When I get the time, I'm going to start writing fun stuff
myself.  I'd also be interested in hearing from anyone with code for job
control in SysV.

Anyone with TLI interface modules for IBM-NETBIOS, and drivers for the
IBM token-ring card, please give me a call!  We're ready to pay cash!
--
						Greg Woods.

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