I am currently trying to make an autonomous drone using the Robot Operating System (ROS). To do this, I have installed Raspbian Lite (Jessie) on a Rasperry Pi 3 and am currently using ROS Kinetic on it. I decided to go with Openbox Window Manager and installed a terminal onto it for convenience. I can just call sudo startx to open up a window manager in another terminal. Since there is no desktop environment, I have also installed tmux for convenience. I am running the xserver on a particular pane and conduct my ROS work on other panes.
Now when I try to run commands that call on a GUI application from my first terminal virtual device (Ctrl + Alt + F1), I get the error:
QxcbConnection: Could not connect to display
Aborted
After a recommendation from this question, I decided to install xhost on my terminal emulator (which is running on my window manager on my second terminal virtual device, that can be accessed by Ctrl + Alt + F2). After invoking xhost + in the same emulator, I get this:
access control disabled, clients can connect from any host
After which I invoke xhost which returns with:
access control disabled, clients can connect from any host
SI:localuser:root
Therefore, in my first virtual terminal device, I have set the environmental variable to 5 different values which have been listed below, and tried to run the program which calls on the $DISPLAY, but I get the same QxcbConnection: Could not connect to display error.
SI:localuser:root
localuser:root
localuser
root
SI:localuser
localhost:0
The last one was actually from the linked question. To my understanding, I am doing exactly what is listed out in this man page. What am I doing wrong?
NOTE
I have also tried ssh'ing into the window manager with ssh root@raspberrypi (which is what I infer the user@hostname to be from the prompt in my terminal emulator inside my window manager). However, this asks me for a password, which I do not know and cannot access. This is the topic for this question.
