ncurses screen/tmux-256color

Question

I have my term set to tmux-256color through .tmux.conf, but I can't get 256 color mode in an ncurses app working. According to this post it should be supported by now. xterm-256color works perfectly fine.

Running the app with:

 env TERM=tmux-256color ./ncurses_app

doesn't work either. The same is true for screen-256color.

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It's using the wide library. Also screen-256color and tmux-256color are installed in the terminfo database.

Is full support for tmux and screen 256color still not in?

Answer 1

That's rather vague: either the terminal entry is installed, or it's not. Systems (such as Debian and those derived from it such as Ubuntu) which default to a "small" terminal database don't install any of the tmux variants.

If you set TERM to something that is not installed, both screen and tmux will give an error and stop. ncurses applications calling initscr also will give an error, and stop.

When using 256-colors, you would need ncurses6 and use the wide-character library, e.g., -lncursesw since the narrow (-lncurses) library supports only up to 16 colors.