gnome-terminal should default to 80x25 for application compatibility

[Dominic Evans]

Binary package hint: qemu-kvm

A minor (but irritating) mismatch in default sizes when running qemu using ncurses rather than SDL.

gnome-terminal defaults to a 80x24 console / window size, whereas starting up `qemu -curses` creates a 80x25 (640x480) console. Thus the bottom row is not visible unless you resize your gnome-terminal window. Unsure if this counts as a gnome-terminal or qemu-kvm bug, but it is a usability mismatch.

qemu-kvm:
  Installed: 0.11.0-0ubuntu6

gnome-terminal:
  Installed: 2.28.1-0ubuntu1

[Dominic Evans (oldmanuk)]

NB: editing /usr/share/vte/termcap/xterm

 xterm-xfree86|xterm-new|xterm terminal emulator (XFree86):\
     :am:km:mi:ms:xn:\
- :co#80:it#8:li#24:\
+ :co#80:it#8:li#25:\

is a workaround

[Dustin Kirkland  (kirkland)]

Adding a gnome-terminal task, as I'm interested in their opinion too.

[Dustin Kirkland  (kirkland)]

From my little perspective, it seems like it would be nice if gnome-terminal defaulted to 80x25. A quick search and a read of wikipedia seems to indicate that 80x25 is the most common format:

 * http://en.wikipedia.org/wiki/80x25

"By far the most common text mode used in DOS environments, and initial Windows consoles, is the default 80 columns by 25 rows, or 80×25, with 16 colors. This mode was available on practically all IBM and compatible personal computers. All 80×25 modes also had a virtual 80×24 mode, used by some applications that needed a status bar on the last row, like terminal emulators. In reality, it was the same 80×25 mode, but restrained by software to make the last row unaccesible."

I'll copy the bug over to gnome-terminal, but I don't really want to get in the middle of flamewar about something like this.

[Dustin Kirkland  (kirkland)]

I'm marking the qemu-kvm task "invalid" as I think qemu is doing the "right thing", by emulating an 80x25 console.

[Dustin Kirkland  (kirkland)]

And for completeness, this is totally configurable in gnome-terminal.

Edit -> Profile Preferences -> Default Size -> 25 rows

[Chris Coulson (chrisccoulson)]

I was going to go ahead and just change the default, but then i tried xterm and terminator and they both default to 24 rows too. Should we consider changing other terminal emulators too?

Would you mind forwarding this upstream for discussion there too

[Dominic Evans (oldmanuk)]

OK, raised upstream.

https://bugzilla.gnome.org/show_bug.cgi?id=611573

[Chris Coulson (chrisccoulson)]

Thanks!

[Dominic Evans (oldmanuk)]

upstream seem to thing that updating the termcap (the 'workaround' in my earlier comment) is the correct fix and should be respected by both xterm and terminator

i.e.,
/usr/share/vte/termcap/xterm

 xterm-xfree86|xterm-new|xterm terminal emulator (XFree86):\
     :am:km:mi:ms:xn:\
- :co#80:it#8:li#24:\
+ :co#80:it#8:li#25:\

so should we raise this against ubuntu/+source/vte ?

[Dustin Kirkland  (kirkland)]

I've opened a vte task, marked it triaged/wishlist.

Hopefully someone familiar with that package can comment as to the viability of the change. Thanks.

[Thomas Dickey (dickey-his)]

The report has several problems. I'll list a few of them.

vte would like to emulate xterm (it's incomplete).
xterm emulates vt100, vt220, etc. Those are all 24x80.

PC's have 25x80. But their emulation of vt100 is weak,
with well-known differences.

Terminator isn't relevant to the topic.

Generally speaking, terminal emulators do not pay much attention to the
termcap data. It's useful (as xterm and gnome-terminal can do) to set function
keys. For sizing the terminal - the use of that via termcap is an archaic feature.

The scrap of termcap in gnome-terminal's source (aside from the fact that an
upstream bug notes that the feature is not working) is purely to enable gnome-terminal
to find the data (for some reason its developers did not use the conventional terminfo
or termcap interfaces to obtain this information).

The comment about wikipedia
(a) misinterprets what is there and
(b) wikipedia is not a reliable source.

[Dominic Evans (oldmanuk)]

@dickey so what is your suggested fix for the usability issue? :-)

[Thomas Dickey (dickey-his)]

On Wed, 3 Mar 2010, Dominic Evans wrote:

> @dickey so what is your suggested fix for the usability issue? :-)

It should be fixed in the qemu package, rather than gnome-terminal
(by making it work with different screensizes).

--
Thomas E. Dickey
http://invisible-island.net
ftp://invisible-island.net

[Anthony Liguori (anthony-codemonkey)]

You can use an ANSI sequence to resize a terminal. The following works in gnome-terminal:

echo -en '\033[8;25;80t' && qemu -curses ...

But it's somewhat impolite to resize a user's terminal automatically though.

[Thomas Dickey (dickey-his)]

On Wed, 3 Mar 2010, Anthony Liguori wrote:

> You can use an ANSI sequence to resize a terminal. The following works
> in gnome-terminal:

technically that's not ANSI (other than the form).
It's one of the dtterm (Sun) sequences that I implemented for xterm.
The security people don't much like it.

> echo -en '\033[8;25;80t' && qemu -curses ...
>
> But it's somewhat impolite to resize a user's terminal automatically
> though.

:-)

--
Thomas E. Dickey
http://invisible-island.net
ftp://invisible-island.net

[Anthony Liguori (anthony-codemonkey)]

I'm marking this as Won't Fix in qemu as it doesn't seem like a good idea for us to automatically resize the terminal for a user.

I'd suggest using a wrapper script if this is a desirable behavior for you.