title: Shell variable issue when trying to mkdir
body: <p>Any ideas what is wrong with this code?</p>
  
  <pre><code>CLIENT_BUILD_DIR="~/Desktop/TempDir/"
  
  if [ ! -d $CLIENT_BUILD_DIR ]
  then
     {
        mkdir $CLIENT_BUILD_DIR
     }
  fi
  </code></pre>
  
  <p>I get the error:  mkdir: ~/Desktop: No such file or directory.</p>
  
  <p>Obviously the directory is there and the script works if I replace the variable with ~/Desktop/TempDir/</p>