Written on May 16, 2005
#!/usr/bin/python import os, sys, random, imghdr # This is a little program I call via cron to change my desktop every # few minutes. With no arguments it goes to my directory of backdrop # images and picks a valid image at random. If I specify a path and a # file the program will put it up as the display. # I don't want to fill up my inbox with emails from cron telling me that # X isn't running, so I check first. xisrunning = os.popen("pidof /usr/bin/X11/X").read() def changebackdrop(): # The below command works for transparent Eterm or Urxvt terminals, # populating their backgrounds with the image they occlude. xli or # xsetroot can be called, but they don't work as desired for # transparent terminals. command = "/usr/bin/Esetroot" # If I was logging into X remotely, this would change. commandargs = " -display :0.0 " # This is where my backdrops live picdir = "/home/willyyam/misc/bmps/" if sys.argv[1:]: doit = command + commandargs + sys.argv os.popen(doit, 'r') else: files = os.listdir(picdir) os.chdir(picdir) pics =  for file in files: # This is a test for valid images - it includes rgb files, # which are not supported by my image software, but the # error thrown is not terrible - it knows what it can and # cannot run. if imghdr.what(file): pics.append(file) randpic = random.choice(pics) doit = command + commandargs + picdir + randpic os.popen(doit, 'r') if xisrunning: changebackdrop() else: exit # Copyright 2005 William Witteman
Filed in: code.