Automatically answering an interactive prompt with "yes"

Question

Some daemons ask if they shall be restarted, when they've got an update. I get asked whether I want to restart them or not. It opens a purple colored window, where I am supposed to navigate to yesor no with my keyboard and then hit "Enter". I am looking for a way to automatically say "yes" in those interactive prompts, so it can be used in scripts. Only using the -y flag, does not work. Neither works yes | apt upgrade. I am still forced to navigate with my keyboard.

Any help is highly appreciated.

Thanks in advance.

Answer 1

Try with the DEBIAN_FRONTEND=noninteractive environment variable set to skip all interactive dialog boxes with the default response:

sudo DEBIAN_FRONTEND=noninteractive apt -y upgrade

See also Automatically answer 'Yes' when using apt-get install on Super User.