[TUHS] cat -v and other complaints

Andy Kosela akosela at andykosela.com
Fri Sep 7 08:16:21 AEST 2018


Norman Wilson <norman at oclsc.org> wrote:

> Andy Kosela:
>
>   One still cannot ignore the fact that Unix and Plan 9 offer two
>   completely different approaches to displaying text.
>
> I admit I've never actually used Plan 9.  Can you elaborate on
> the different approaches?
>
> One difference from most of what passes for UNIX these days is
> probably that the basic terminal model allows one to edit anything
> on the screen, using the mouse and keyboard and a simple button-2
> menu similar to that of sam.  You can edit what some program has
> already printed, then pick it up and send it back as input.  You
> can even edit text in the current line that hasn't been sent yet
> (because you haven't hit a return yet); in effect the canonical-line
> part of the tty driver is in the terminal.
>
> But you probably don't mean that, both because it's not really
> such a radical difference, and because it doesn't conflict at all
> with UNIX.  In fact it originated on UNIX, five or six years before
> Plan 9 was thought of: it's the model from the terminal program
> in mux, the more-advanced version of the Blit/Jerq window manager
> that nearly everybody used in 1127 by the time I arrived in 1984.
>
> And I still use it every day, even on Linux (and in years past
> on Solaris and IRIX and Digital UNIX and Ultrix).  The modern
> version of the program to do that is called 9term.  It doesn't
> work quite as well as I'd like on Linux due to changes in the
> tty driver that make it hard for a program to learn right away
> when tty modes are changed (in particular when echo is turned off
> or on), and it does conflict with the GNU readline junk because
> that turns off canonical processing, but to those of us who have
> a taste for it it's still just fine.
>
> As I say, I don't think that's the difference you mean, so please
> step in and supersede me.

In short, character based approach vs. bitmap based.  Yes, in Unix you
also has a windowing system which is bitmap based, but IMHO this was
always an add-on and not an essential part of the system.  Plan 9 on the
other hand seems to be designed with more of a graphical based approach
than the old school character based approach.

--Andy



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