Scripts launched from udev do not have DISPLAY access anymore?

I have a script that runs from udev when I plug in my external drive. It always worked. But after upgrading from Linux 3.8/Xorg 1.12/Mint 14 (Ubuntu 12.10 compatible) to Linux 3.11/Xorg 1.14/Mint 16 (Ubuntu 13.10 compatible), it doesn't work anymore.

The script still runs, but none of the commands that require the display work. I figured that out by quitting the udev daemon and manually run udevd --debug for verbose output (more below).

This script used to work in Mint 14/12.10:

export DISPLAY=:0UUID=$1DEV=$2notify-send -t 700 "mounting $DEV ($UUID)"gnome-terminal -t "Backing up home..." -x rsync long line of datazenity --warning --text="Done."

But not anymore in Mint 16/13.10. In case you are wondering about possible solutions, I gradually added stuff and now it looks like this:

export DISPLAY=:0.0xhost +local:xhost +si:localuser:rootxhost +DISPLAY=:0.0export DISPLAY=:0.0UUID=$1DEV=$2notify-send -t 700 "mounting $DEV ($UUID)"gnome-terminal -t "Backing up home..." -x rsync long line of datazenity --warning --text="Done." --display=:0.0

But it still doesn't work. udevd --debug still shows this:

'(err) 'No protocol specified''(err) '''(err) '** (gnome-terminal:24171): WARNING **: Could not open X display''(err) 'No protocol specified''(err) 'Failed to parse arguments: Cannot open display: ''(err) 'No protocol specified''(err) '''(err) '** (zenity:24173): WARNING **: Could not open X display''(err) 'No protocol specified''(err) '''(err) '(zenity:24173): Gtk-WARNING **: cannot open display: :0.0''(err) 'No protocol specified'

Note that any bash logic works. Echoing test vars to >>/tmp/test.log works. It's just accessing the display that does not work anymore.

This is driving me crazy. What is the correct way to achieve this now?

Update 2013-12-20

So, in the previous Ubuntu, X commands would automatically find it's way to the current X using user.

Now, I seem to need these two things every time:

• On the X using user:
  • xhost +si:localuser:root
• On the root/udev side:
  • Copy X using users'~/.Xauthority file to /root

This 'feels' like a step back in time. This only works scripted when I log in as the same user everytime, so I can copy the .Xauthority file from that users' home when the script executes.

What 'trick' did the old Ubuntu use to have this done auto'magic'ally?