title: Perl unicode formatting issue
body: <p>Why doesn't this sample code work correctly?</p>
  
  <pre><code>#/usr/bin/perl
  
  $a = "aaa%29";
  $a =~ s/%/\\x/g;
  print "a  $a \n";
  $b = "aaa\x29";
  print "b  $b \n";
  $c = sprintf($a);
  print "c  $c \n";
  </code></pre>
  
  <p>I want to get three times the same output line.</p>