I'm trying to change the desktop wallpaper via cron/bash. I've read a lot of questions and answers on this site an apparently I have to do something like
#!/bin/bash
MY_FILE_PATH=/home/$USER/file.jpg
PID=$(pgrep gnome-session)
export DBUS_SESSION_BUS_ADDRESS=$(grep -z DBUS_SESSION_BUS_ADDRESS /proc/$PID/environ|cut -d= -f2-)
sleep 5
gsettings set org.gnome.desktop.background picture-uri file://$MY_FILE_PATH
But if run ./my_script.sh I get
grep: /proc/X1: Is a directory
grep: X2/environ: No such file or directory
X1 and X2 are two different numbers and of course cron doesn't work
EDIT
If I manually set PID to one of the two numbers I get (on the line where export is made)
for X1 (829):
permission denied
for X2 (1394):
warning: command substitution: ignored null byte in input
