mjhjmtu

I need to start firefox-esr once the network is available.

Here's what I've got:

sudo tee "/etc/network/if-up.d/upif" > /dev/null << EOFBOOT
#!/bin/bash
DISPLAY=":0"
if [[ "$IFACE" = "eth0" || "$IFACE" = "wlan0" ]]; then
 echo "$(date) $IFACE" >> /var/log/upif
 firefox-esr &
fi
EOFBOOT
sudo chmod +x "/etc/network/if-up.d/upif"

I am getting the date and the interface name in my log file, which means the script runs, but firefox-esr doesn't start.

What I've tried:

• adding DISPLAY=":0"
  


• grep -inR "firefox" /var/log


• using full path to executable, i.e. /usr/bin/firefox-esr
  


• using sudo firefox-esr &
  


• removing the trailing &
  

Nothing helped. However, if I put IFACE="eth0" below the shebang and then run sudo /etc/network/if-up.d/upif manually, that exact script you see above does the job and starts firefox.

I am not sure what's the problem there. Spent few hours on it already. Please help!

This is 2018-06-27-raspbian-stretch-lite running Debian 9.4.

P.S. Also I initially had logic checking whether Firefox already runs before attempting to start it, but once I realised Firefox isn't launched at all, I removed it

UPDATE Found a similar problem: Start a GUI in NetworkManager if-up.d script

The network event scripts run as the root user, but your desktop environment probably (hopefully) isn't.

This seems like a problematic approach in general. A few things are missing:

• Firefox should run as your logged in user, not root.


• Firefox needs to be able to authenticate to the X server to connect to it (see ~/.Xauthority and man xauth).


• Firefox's environment needs to be set up to work properly in the desktop session (HOME, XDG_RUNTIME_DIR etc.)

I would suggest trying a different approach, e.g. having the network script communicate network status (via a pipe / temporary file / DBus) to something already running in the user session (launched e.g. from ~/.xinitrc), which then launches GUI apps as needed.

Thanks to Fadabi Nawi, here's what the answer was:

su pi -c "DISPLAY=:0.0 /usr/bin/firefox-esr &"

Key points:

• su to the actual user you normally use (pi in my case)


• pass the display number right there (TODO: find out the actual display number instead of assuming it's :0)


• 
  important use the full path to Firefox executable, instead of firefox-esr