Non-functional in tmux and/or st about cli-visualizer

[dpayne]

For both the tmux issue and the st one solution is to set TERM to xterm-256color, urxvt-256color also seemed to work for me. This can be done at compile time when building st using this method https://wiki.archlinux.org/index.php/St#Term or by running export TERM='xterm-256color'. The compile time way seems to be the recommended way for st. Note that both basic and 256 colors should be supported.

Please update this thread if you still have issues or if you find a better way.

[dpayne]

My initial guess is that tmux doesn't support 256 colors. Could you try with a different color scheme? The color scheme can be defined in the colors directory, usually under ~/.config/vis/colors/. The config option colors.scheme can be used to set the color scheme.

For example, copy the file copying the colorscheme blue to ~/.config/vis/colors/blue then set colors.scheme=blue.

[HalosGhost]

Both tmux and st have support for 256 color, and I have my terminfo set to tmux-256color which is the correct one for such a thing (available since ncurses 6).

In addition, I tried changing the color scheme to basic_colors and I still got the blank screen.

[dpayne]

Does it work with st without tmux?

Also if you're willing to debig some more, could you try checking out this branch git checkout always_enable_colors and building again. This branch always enables colors even if the terminal claims to not support it.

[HalosGhost]

Yesterday, it did not work in st even when not under tmux. But in a terminal where it does work, it stops working under tmux. If these should be separated to two separate issues, that's fine :)

I will checkout that branch and give it a shot! No joy in st. If it matters, no bars are showing up whatsoever, it's a completely blank screen.

[dpayne]

Would you mind pulling the branch always_enable_colors another time. I've made one other change to always enable 256 colors. So far I've been unable to reproduce this with tmux, it is working with the latest arch linux packages.

[HalosGhost]

All right, I have an update. First, it seems I may have made a foolish mistake earlier and passed ENABLE_PULSE=1 after make instead of before. However, after having changed it, vis still produces no visible output in st.

However, after making sure to pass it as an environment variable, the same thing happens: it works in terminals other than st, but not inside tmux and it does not work in st at all.

[HalosGhost]

@dpayne, so the issue then is that vis is incompatible with both terminfos tmux-256color and st-256color?

[dpayne]

So the actual issue is pretty annoying. vis uses ncurses, which in turn uses $TERM to figure out what colors are supported and how to output them since different terminals have different escape codes. So for example when tmux is run without setting $TERM, vis still works it is just that all the colors are either black or transparent. You can see this if you set your terminal to transparent, then some sections of the bars will show up black and some clear. It is harder to say what exactly is going on with st, but I imagine something very similar is going on.

The two solutions I see are either stop using ncurses or have the user set the $TERM variable, both solutions are terrible with the second being slightly less so. If I removed ncurses there would be even more issues with various terminals since ncurses handles a lot of the peculiarities of some terminals. I really do not like that the user has to set a shell variable, but the alternative of abandoning ncurses is not going to happen anytime soon.

[HalosGhost]

Well, actually, it sounds like you have an implicit dependency on xterm/urxvt's terminfo. $TERM declares the terminfo to use, but I have it set (I just have it set to tmux-256color when in tmux and st-256color when in st without tmux).

Note that both of these terminfos support 256 colors. It seems rather that you may be calling the escapes from xterm/urxvt rather than querying the set terminfo to see which escapes to use. (I have not yet looked at your code, but since the workaround is to just set TERM=xterm-256color, that seems most likely.)

[dpayne]

I do not use $TERM anywhere in the code, however ncurses does. From the docs http://linux.die.net/man/3/ncurses

 TERM
   Denotes your terminal type. Each terminal type is distinct, though many are similar.

The current version of ncurses does not recognize tmux-256color or st-256color so it assumes a default that clearly does not work.

[HalosGhost]

Which version of ncurses are you referring to? The latest version (at least on Arch) provides both tmux-256color and st-256color. See below:

$ pacman -Qi ncurses|grep Version
Version        : 6.0-4
$ pacman -Ql ncurses|grep -e 'st-256color' -e 'tmux-256color'
ncurses /usr/share/terminfo/s/st-256color
ncurses /usr/share/terminfo/t/tmux-256color

[dpayne]

You are right. I was using a custom version of ncurses but the latest version appears to have it, but I still see the same issue. However this just makes the issue more perplexing. vis does not use terminfo directly in any way, it always goes through ncurses.

[HalosGhost]

I will take a look at the code this weekend and see if I cannot figure out what may be going on. Thank you for your time, regardless!

[dpayne]

Could you run tput colors with tmux and in st?

On my system, with tmux I get 8 even though 256 colors should be supported. After running export TERM='xterm-256color', tput colors shows 256 and vis will show all colors. Again, thanks for all the work investigating this; this is definitely an issue just one I do not see a good solution to. Please update this thread or open another issue if you find a better solution.

[HalosGhost]

tput colors shows 256 in both tmux and st. You may have 8 showing up because tmux does not default to using tmux-256color, but that is what I have it set to use.