Background-changer script for GNOME 3

background

#!/bin/bash
# background-changer
# 2012-04-06
# use to switch gnome background to a random one
# uses every file in bg_path and follows the first symlinks in that directory
# outputs the selected file
# author: cfstras <c@cfs.im>
# license: beerware
# 
# use for example in a crontab:
# 0,15,30,45 * * * * background >>/tmp/background.log 2>&1
#

bg_path="/wallpapers"
exts=".jpg
.png
.PNG
.JPG
.JPEG
.bmp
.BMP
.gif
.GIF
.JPEG
.jpeg
.tiff"


#set Display
DISP="$(cat /proc/$(pgrep -u `whoami` gnome-session)/environ | tr "\0" "\n" | grep DISPLAY)"
[ "$DISP" ] || die "background: Unable to get DISPLAY variable from environment"
eval export "$DISP"

selected_bg=`find -H $bg_path/* -type f | grep -F "$exts" | sort -R | tail -n1`

gsettings set org.gnome.desktop.background picture-uri "file://$selected_bg"

echo "`date "+%y-%m-%d %T"` new background: "$selected_bg
notify-send --hint=int:transient:1 "new background: "$selected_bg