Usage in GNU screen broken?

[lingfish]

Is GNU screen supported? I run a fairly stock config of screen under Alacritty, and this is what I see with the demo:

If I exit screen and re-run, it looks fine.

[TomJGooding]

It will be helpful if you run the following command and paste the results:

textual diagnose

If you don't have the textual command on your path, you may have forgotten to install the textual-dev package.

[lingfish]

Yes, of course, oops. Here it is inside screen:

Inside screen

# Textual Diagnostics

Versions

Name	Value
Textual	0.79.1
Rich	13.8.1

Python

Name	Value
Version	3.11.2
Implementation	CPython
Compiler	GCC 12.2.0
Executable	/srv/virtualenv/multimon-ng-pretty-wU1IQLii/bin/python

Operating System

Name	Value
System	Linux
Release	6.1.0-23-amd64
Version	#1 SMP PREEMPT_DYNAMIC Debian 6.1.99-1 (2024-07-15)

Terminal

Name	Value
Terminal Application	Unknown (inside screen)
TERM	screen
COLORTERM	truecolor
FORCE_COLOR	Not set
NO_COLOR	Not set

Rich Console options

Name	Value
size	width=192, height=57
legacy_windows	False
min_width	1
max_width	192
is_terminal	True
encoding	utf-8
max_height	57
justify	None
overflow	None
no_wrap	False
highlight	None
markup	None
height	None

And this is outside of screen:

alacritty only

Textual Diagnostics

Versions

Name	Value
Textual	0.79.1
Rich	13.8.1

Python

Name	Value
Version	3.11.2
Implementation	CPython
Compiler	GCC 12.2.0
Executable	/srv/virtualenv/multimon-ng-pretty-wU1IQLii/bin/python

Operating System

Name	Value
System	Linux
Release	6.1.0-23-amd64
Version	#1 SMP PREEMPT_DYNAMIC Debian 6.1.99-1 (2024-07-15)

Terminal

Name	Value
Terminal Application	Unknown
TERM	alacritty
COLORTERM	truecolor
FORCE_COLOR	Not set
NO_COLOR	Not set

Rich Console options

Name	Value
size	width=192, height=58
legacy_windows	False
min_width	1
max_width	192
is_terminal	True
encoding	utf-8
max_height	58
justify	None
overflow	None
no_wrap	False
highlight	None
markup	None
height	None

[TomJGooding]

I finally had some success with screen and alacritty with this setting:

~/.screenrc

term screen-256color
unsetenv COLORTERM
altscreen on

I think the problem is that screen doesn't support true colors, but the COLORTERM was being set by alacritty.

However, there's still an issue where the app output isn't cleared on exit when run within screen (although I just tested with vim and its output isn't cleared on exit either) Fixed the output not clearing by also setting altscreen on

Edit: Apparently true colors are supported in screen v5.0.0 with truecolor on!

[lingfish]

Ok, so here's what I discovered.

• The TERM setting, ending in 256color, matters (eg. screen-256color or xterm-...) -- having just screen isn't enough
• The COLORTERM=truecolor matters -- no matter what else is set, this breaks it for me

So essentially, unset COLORTERM before anything else... then, with just TERM=screen, I get what perhaps looks like 8 bit colors (no surprise, halfway there). If I run TERM=xterm-256color pipenv run python -m textual, I get a much better looking screen. Same with the screen-25... variant.

[lingfish]

Fixed the output not clearing by also setting altscreen on

Right, like the old-school xterm. Funny, I dislike that behaviour 😆 Can it not just place the cursor at the bottom of the terminal on exit?

[Yurii-huang]

You can't use a color scheme, and any program's screen will be displayed in black and white. The premise of using color should first confirm whether the color screen configuration is supported, I have a good scenario for using Tmux, obviously Tmux supports xterm-256color

[lingfish]

You can't use a color scheme, and any program's screen will be displayed in black and white. The premise of using color should first confirm whether the color screen configuration is supported, I have a good scenario for using Tmux, obviously Tmux supports xterm-256color

I'm not sure what you point is here.