Update PATH Variable in Byobu for root

Question

I would like to add a directory to the $PATH variable for all users, including users who run byobu with sudo byobu.

I am running Ubuntu 22.04 LTS on x86_64.

The desired path is below. Note the presence of cuda-12.3:

/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin:/usr/local/cuda-12.3/bin

I updated /etc/environment to include this line:

PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin:/usr/local/cuda-12.3/bin"

That is sufficient to set $PATH for users and for root.

username:~$ echo $PATH
/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin:/usr/local/cuda-12.3/bin

$ sudo su
# echo $PATH
/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin:/usr/local/cuda-12.3/bin

It is also sufficient to update path when launching byobu as a regular user.

$ echo $PATH
/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin:/usr/local/cuda-12.3/bin

The issue occurs when I start sudo byobu and get the $PATH.

$ sudo byobu
# echo $PATH
/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/snap/bin

Notice that cuda-12.3 is missing, as are other directories.

I tried editing the following locations, but all failed to set $PATH correctly when running sudo byobu.

• /etc/profile
• /usr/share/byobu/profiles
• /root/.profile

I have referred to these posts:

• PATH variable not getting updated according to /etc/environment
• Where is the system-wide $PATH variable set?
• https://stackoverflow.com/questions/14637979/how-to-permanently-set-path-on-linux-unix