Windows Bash (WSL) - sudo: no tty present and no askpass program specified

Question

After following this tutroial I get the following error when trying to run the commands as user or even sudo:

sudo: no tty present and no askpass program specified

The comments from Lurdan in this article state that you need to run

sudo -S <YOUR_COMMAND>
chmod 0666 /dev/tty

chmod doesn't work but sudo -S does, but surely there's another fix?

Answer 1

So silly, after looking further down I see a solution from Beorat:

To avoid the sudo tty issue and others, run these commands just before running do-release-upgrade:

sudo -S apt-mark hold sudo
sudo -S apt-mark hold procps
sudo -S apt-mark hold strace

If you've already upgraded, run the above commands, then manually downgrade to the Trusty packages:

sudo -S wget http://mirrors.kernel.org/ubuntu/pool/main/s/sudo/sudo_1.8.9p5-1ubuntu1.1_amd64.deb
sudo -S wget http://mirrors.kernel.org/ubuntu/pool/main/p/procps/procps_3.3.9-1ubuntu2_amd64.deb
sudo -S wget http://mirrors.kernel.org/ubuntu/pool/main/s/strace/strace_4.8-1ubuntu5_amd64.deb
sudo -S dpkg -i sudo_1.8.9p5-1ubuntu1.1_amd64.deb
sudo -S dpkg -i procps_3.3.9-1ubuntu2_amd64.deb
sudo -S dpkg -i strace_4.8-1ubuntu5_amd64.deb

More info here: https://github.com/Microsoft/BashOnWindows/issues/482

Answer 2

WSL uses the lxrun executable for management from Windows:

lxrun -h

Usage:
    /install - Installs the subsystem
        Optional arguments:
            /y - Do not prompt user to accept
    /uninstall - Uninstalls the subsystem
        Optional arguments:
            /full - Perform a full uninstall
            /y - Do not prompt user to accept
    /setdefaultuser - Configures the subsystem user that bash will be launched as. If the user does not exist it will be created.
        Optional arguments:
            username - Supply the username
            /y - If username is supplied, do not prompt to create a password
    /update - Updates the subsystem's package index

Given that, you can use lxrun /setdefaultuser root. Just thought I'd point out this side of it since it was required when I ran into the same issue as you after trying to upgrade to Xenial. I can confirm that running this command, then the wget / dpkg commands my issues were resolved.

The commands I used:

wget http://mirrors.kernel.org/ubuntu/pool/main/s/sudo/sudo_1.8.9p5-1ubuntu1.4_amd64.deb
wget http://mirrors.kernel.org/ubuntu/pool/main/p/procps/procps_3.3.9-1ubuntu2_amd64.deb
wget http://mirrors.kernel.org/ubuntu/pool/main/s/strace/strace_4.8-1ubuntu5_amd64.deb
dpkg -i sudo_1.8.9p5-1ubuntu1.4_amd64.deb
dpkg -i procps_3.3.9-1ubuntu2_amd64.deb
dpkg -i strace_4.8-1ubuntu5_amd64.deb

Finally, you might need to run sudo apt-get install -f in case you get The following packages have unmet dependencies [xxx] but it is not going to be installed

Answer 3

I got rid of the error by moving /etc/hosts to /etc/hosts.bu. After closing the shell en opening again, /etc/hosts is recreated and your computer name is added. The error is gone (for me.)