title: Split a UTF-8 encoded string on blank characters without knowing about UTF-8 encoding
body: <p>I would like to split a string at every blank character (' ', '\n', '\r', '\t', '\v', '\f')
  The string is stored in UTF8 encoding in a byte array (char*, or vector or string, for instance)</p>
  
  <p>Can I just split the byte array at each splitting character? Said otherwise, am I sure that the byte values corresponding to these characters cannot be found in a multi-byte character? By looking at the UTF-8 spec it seems all multibyte characters have only bytes higher than 128.</p>
  
  <p>Thanks</p>