title: (grep) Regex to match non-ASCII characters?
body: <p>On Linux, I have a directory with lots of files. Some of them have non-ASCII characters, but they are all valid <a href="http://en.wikipedia.org/wiki/UTF-8" rel="noreferrer">UTF-8</a>. One program has a bug that prevents it working with non-ASCII filenames, and I have to find out how many are affected. I was going to do this with <code>find</code> and then do a <a href="http://en.wikipedia.org/wiki/Grep" rel="noreferrer">grep</a> to print the non-ASCII characters, and then do a <code>wc -l</code> to find the number. It doesn't have to be grep; I can use any standard Unix <a href="http://en.wikipedia.org/wiki/Regular_expression" rel="noreferrer">regular expression</a>, like <a href="http://en.wikipedia.org/wiki/Perl" rel="noreferrer">Perl</a>, <a href="http://en.wikipedia.org/wiki/Sed" rel="noreferrer">sed</a>, <a href="http://en.wikipedia.org/wiki/AWK" rel="noreferrer">AWK</a>, etc.</p>
  
  <p>However, is there a regular expression for 'any character that's not an ASCII character'?</p>