Bash script to open tmux but can't see username

Question

I have a bash script that starts a tmux session with some monitoring tools, and have a cronjob that runs it on startup; however, I can't see the usual prefix to my commands, and I can't use any arrow keys.

Normally it should look like this:

(the actual script)

#!/bin/sh

cd /home/ubuntu/

tmux start-server

tmux new-session -d -s "0" bash
tmux selectp -t 1
tmux splitw -h -p 50
tmux selectp -t 2
tmux splitw -v -p 50
tmux selectp -t 3
tmux send-keys "htop" C-m

# Select pane 1
tmux selectp -t 0
tmux attach-session -t "0"
tmux detach

What went wrong??

Answer 1

It looks like you cron job started sh or dash instead of bash (Ubuntu made a difference between bash and sh... I don't know if it is still the case). You should be able to check this with a ps ux when your cron-tmux is running.

If a real bash was started, maybe it didn't source ~/.bashrc: try /bin/bash -i, or manually source it in your script.

Also, within a cron job, the environment is usually minimal. Type env in your tmux session to see what is available, this could give you a clue.

If your cron is run as root (you didn't mention, so I assumed as user), his bashrc may be minimal or inexistant, hence the ugly cmdline.