1  # Stop & backup
   2  xm stop sandbox
   3  cp -a sandbox/ sandbox.bk
   4  
   5  # Verify MD5 sum
   6  md5sum sandbox/disk.img 
   7  4976347006df34843d29c939b5fc3742  sandbox/disk.img
   8  md5sum sandbox.bk/disk.img 
   9  4976347006df34843d29c939b5fc3742  sandbox.bk/disk.img
  10  
  11  # Create a 5Gb temp file
  12  dd if=/dev/zero of=Tempfile bs=1024 count=5000000
  13  
  14  # Append it to the existing image
  15  cat Tempfile >> disk.img
  16  rm Tempfile
  17  
  18  # Resize the partition
  19  resize2fs -f disk.img
  20  
  21  # Check partition & start domU
  22  fsck.ext3 disk.img
  23  xm create -c sandbox.cfg

   1  Dir.glob("**/*.{jpg,gif,jpeg,png}").sort.each do |image|
   2  
   3    name   = File.basename(image)
   4    in_use = false
   5    
   6    Dir.glob("**/*.{erb,css,js,html,htm}").each do |file|
   7      contents = File.read(file)
   8  
   9      in_use = contents.include?(name)
  10      
  11      break if in_use
  12    end
  13  
  14    if !in_use
  15      puts "Deleting '#{image}'"
  16      File.delete(image)
  17    end
  18  end

This is currently my favorite image replacement technique. I don’t remember where I found it… Using it can improve both your site’s usability and your search engine ranking, by allowing both screen readers and search engines to find your h1 headlines. First create the h1 and the description of your page/site, for example:

   1  <h1 id="logo">Viagra, Botox, you name it</h1>

Then create the CSS rule for the page title:

   1  h1#logo {
   2    text-indent: -9000px;
   3    background: url(logo.gif);
   4    width: 200px; /* Width of image */
   5    height: 50px; /* Height of image */
   6  }

People using a modern browser that support CSS will see your logo (the image), and search engines and people using less modern browsers will see the content of the h1 header tag.

Note that if you replace the text of a link then use the outline CSS property to remove the dotted border:

   1  .text-replacement {
   2  	text-indent: -9000px;
   3  }
   4  
   5  .text-replacement a {
   6  	outline: none;
   7  }