title: Can rmdir be used recursively?
body: <p>The manpage only gives these options:</p>
  
  <pre><code>      --ignore-fail-on-non-empty
                    ignore each failure that is solely because a directory
                    is non-empty
    -p, --parents   Remove DIRECTORY and its ancestors.  E.g., `rmdir -p a/b/c' is
                    similar to `rmdir a/b/c a/b a'.
    -v, --verbose   output a diagnostic for every directory processed
        --help     display this help and exit
        --version  output version information and exit
  </code></pre>
  
  <p>How would I pipe a <code>find</code> or <code>ls</code> to recursively delete all empty directories in a file tree?</p>