confusing scrollbar behavior in gnome-terminal when using screen-profiles

[Jamie Strandboge]

Binary package hint: screen-profiles

After using screen-profiles for a bit, I've noticed rather odd scrollbar behavior in gnome-terminal. To reproduce:

1. install screen-profiles
2. open gnome-terminal
3. select-screen-profile
4. screen
5. ls -lR /

Normal gnome-terminal behavior is to pin the scrollbar slider to the bottom, and then moving the scrollbar up scrolls back. However with screen-profiles, the gnome-terminal scrollbar slider moves up as the 'ls -lR' output scrolls. As soon as you try to move the scrollbar it 'resyncs' (for lack of a better word) and operates normally.

$ lsb_release -rd
Description: Ubuntu jaunty (development branch)
Release: 9.04
$ apt-cache policy screen-profiles
screen-profiles:
  Installed: 1.19-0ubuntu1
  Candidate: 1.19-0ubuntu1
  Version table:
 *** 1.19-0ubuntu1 0
        500 http://127.0.0.1 jaunty/main Packages
        100 /var/lib/dpkg/status

ProblemType: Bug
Architecture: amd64
DistroRelease: Ubuntu 9.04
Package: screen-profiles 1.19-0ubuntu1
PackageArchitecture: all
ProcEnviron:
 PATH=(custom, user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: screen-profiles
Uname: Linux 2.6.28-6-generic x86_64

[Dustin Kirkland  (kirkland)]

I'll mark confirmed, since I see the same behavior.

However, this is a direct result of our "enabling" of gnome-terminal's scroll bar.

If you select-screen-profile and choose the plain (system default), you won't see this behavior. However, you also won't be able to scroll at all using your gnome-terminal scroll bars.

It's the line:
termcapinfo xterm* ti@:te@

That enables this. There may be some other magic that could pin your scroller at the bottom, but I don't know it.

:-Dustin

[Dustin Kirkland  (kirkland)]

There have been a few questions about scrolling, I suppose I'll answer those here...

In a single window, you can do something like:
 $ ls -alF /usr/bin

You can then use shift-pageup to move up through the lengthy results.

Create a new window, with F2. If you shift-pageup, you'll move through the previous ls results.

It's important to understand that you have access to two separate buffers... That of gnome-terminal, and that of screen.

To scroll through gnome-terminal's buffer, you would use shift-page(up/down), the scrollbars to the right, or the mouse-wheel.

To scroll through screen's buffer, you would hit F7 (to enter copy/scrollback mode), and then maneuver using up/down/pageup/pagedown. You hit escape to exit scrollback mode.

gnome-terminal has no knowledge of windows created within screen. However, screen does. So each window within screen has its own scrollback, which can be viewed in scrollback mode (F7).

:-Dustin

[toobuntu (toobuntu)]

FYI - When using mrxvt or aterm, I am only able to scrollback by using screen's scrollback mode (F7). The mrxvt and aterm scrollbars I have configured are deactivated in essence. When I try Shift-PageUp/Dn all I get is gibberish on the screen in mrxvt and nothing at all in aterm.

mrxvt:
Shift-PageUp = 2~
Shift-PageDn = ;2~

Separately, F2 in aterm does nothing. F2 in mrxvt does not give me a new screen window, either. Rather, it seems to generate a carriage return followed by a capital A on the new line:

$
$ A

Because I followed Nick Barcet's ideas about changing the escape key to w and modded the caption and hardstatus lines (I prefer cyan text against a black background), I am attaching my .screenrc.

Finally, and I know this is not really the proper place to mention it...but...couldn't all the dot files be neatened up in a .screen/ directory?

[Dustin Kirkland  (kirkland)]

Thanks for the reply, toobuntu.

As for the other terminals (mrxvt, aterm), I'll have to do some testing.

> Finally, and I know this is not really the proper place to mention it...
> but...couldn't all the dot files be neatened up in a .screen/ directory?

Good idea. See Bug #335275. I'm fixing that one shortly. In the future, please open a new bug for a request like this, and I'll work on it ;-)

:-Dustin

[Dustin Kirkland  (kirkland)]

Okay, in a future version (post-Jaunty) of screen-profiles, I'm considering dropping "termcapinfo xterm* ti@:te@" from the common profile, and perhaps supporting a toggle for this being turned on/off.

It's a lot easier to turn on, after the fact, than turn off, unfortunately.

Dropping this would disable scrollbars altogether (ie, no scrollbars in xterm, no shift-pgup). Of course, you could still scroll with copy-mode (F7). I'm afraid there might be lashback from users, so I'll put this off until post-Jaunty.

:-Dustin

[pingou67 (pingou67)]

for information, I tested with konsole and the scrollbar works fine (with termcapinfo xterm* ti@:te@), it's a specific gnome-terminal + screen combination bug

[Dustin Kirkland  (kirkland)]

Thanks for the information. I'll add gnome-terminal as affected, and confirm the bug there. Hopefully a gnome developer can help out with this.

:-Dustin

[Dustin Kirkland  (kirkland)]

Marking won't fix against screen-profiles, and copying bug over to new byobu package. If this can be fixed, I'll fix it there.

:-Dustin

[Dustin Kirkland  (kirkland)]

Marking invalid, and converting to a question. Launchpad hates me, so I'm going to create a new question, and link here.

:-Dustin

[Dustin Kirkland  (kirkland)]

See:

Question #76785

:-Dustin