SBT Error: “Failed to construct terminal; falling back to unsupported…”

Question

I have run into an ERROR with SBT today. It can best be shown with the sbt sbt-version command:

Run on 5/29/17:

eric@linux-x2vq:~$ sbt s         


        

Answer 1

I had the same issue, especially when the TERM environment variable is set to xterm-256color. Setting it to a different value fixed the issue for me, e.g.

export TERM=xterm-color

Answer 2

I found the package which causes this issue: ncurses. I downgraded ncurses to version ncurses-6.0+20170429-1 (I am using Arch Linux) and SBT starts just fine.

Steps for Arch Linux:

cd /var/cache/pacman/pkg
sudo pacman -U ncurses-6.0+20170429-1-x86_64.pkg.tar.xz # or some other older version

Steps for Mac: see https://github.com/jline/jline2/issues/281

I think this issue was introduced with ncurses version 20170506, see: http://invisible-island.net/ncurses/NEWS.html#index-t20170506

+ modify tic/infocmp display of numeric values to use hexadecimal when
      they are "close" to a power of two, making the result more readable.

I filed an issue on the SBT issue tracker: https://github.com/sbt/sbt/issues/3240

Edit: SBT version 0.13.16 includes the fix for this problem.

Answer 3

One year passed... now it happened to me.

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So, ncurses did change, and the corresponding sbt part was ...I guess... probably only implemented based on random guessed tests and observations/bugs and not any spec nor RFC. (So far, sbt is the only program with this ncurses issue that I know of.)

In case you can't simply upgrade sbt nor downgrade ncurses, you could change the TERM environment variable as mentioned in the other answers.

trivial fix:

If your sbt script is some bash script (most likely, unless you run DOS' .bat files)

$ file /usr/bin/sbt
/usr/bin/sbt: Bourne-Again shell script, ASCII text executable

, then it might suffice to add this workaround:

TERM="${TERM/xterm-256color/xterm-color}"

Answer 4

I can't write a comment as my score is too low, but user3113045's answer worked when I added export TERM=xterm-color to my .zshrc file

Answer 5

For Ubuntu 20.04 Users, Open your terminal and run the bellow CMDs

• Go to this "/usr/share/sbt/bin" directory ( $ cd /usr/share/sbt/bin )
• give the permission to edit file ( $ sudo chmod -R 777 sbt )
• Open the sbt text file in this directory ( $ nano sbt )
• Add this "export TERM=xterm-color" cmd in top and save ( Ctrl + X )

Ex:-

#!/usr/bin/env bash
export TERM=xterm-color
set +e

Answer 6

sbt command is just a script. It load $HOME/.sbtconfig at the very beginning, so just put

export TERM=xterm-color

as @user3113045 said in the conf file, sbt will work. In that case your other term commands will still use xterm-256color.