Re: Experiences with FreeBSD 9.0-BETA2

Hi Brett,

* Brett Glass <brett_at_lariat.net>, 20111007 15:40:
> The patch is an improvement. Not assuming that tabs blank the underlying
> cells is definitely a help. But it does not fix all of the artifacts.

Just let me know what's broken specifically. So what keys to press when
I start jove to reproduce it. I'm really not familiar with Emacs.

> It might be a good idea to review the "xterm" termcap entry, capability
> by capability, to make sure that syscons conforms to each one. As the
> author of a very exacting vt100 emulator (I wrote Borland's "Turbo Terminal"
> back in the 80s), I know just how quirky, poorly documented, and buggy some
> terminals can be. I had to emulate every strange behavior and bug in the
> vt100 without access to the source code that the embedded CPU was running.
> In general, the behaviors that cause the most problems are wrapping and
> unwrapping text, writing past the edges of the screen, positioning near
> the edges of the screen, and manipulating the top and bottom lines. The
> vt100, for example, would not scroll when you wrote the last character on
> a line, but would then scroll if you entered one character after that
> without executing a command that repositioned the cursor. It would also
> ignore linefeeds after automatic scrolling (due to DEC's convention that
> text files have both a CR and an LF at the end of each line rather than
> just an LF as in UNIX). If you'd like, I can try to come up to speed on
> the code and help to debug, but I do not use X and so have no experience
> with its default terminal emulator; I'd have to study that as well.

Well, apart from small bugs here and there, it should be pretty
conformant already, especially when compared to various graphical
terminal emulators (e.g. GNOME terminal). For example, it passes quite a
large number of tests from vttest.

A nice thing about the terminal emulator is that it can be compiled in
userspace as well:

	cd /sys/teken/libteken
	make
	make install clean
	cd ../demo
	make
	./teken_demo

This will spawn a demo application that renders the terminal using
ncurses.

-- 
 Ed Schouten <ed_at_80386.nl>
 WWW: http://80386.nl/