title: Boost 1.59.0 how do I clean the project?
body: <p>I built the project once, so it generated a bunch of .o and .a files.  Now, I am trying to clean it.</p>
  
  <p>This page: <a href="http://www.boost.org/build/doc/html/bbv2/overview/invocation.html" rel="noreferrer">http://www.boost.org/build/doc/html/bbv2/overview/invocation.html</a> tells me that <code>b2 --clean-all</code> or <code>b2 clean</code> should work.</p>
  
  <p>However, I tried:</p>
  
  <pre><code>  b2 clean
    b2 --clean
    b2 --clean-all
  </code></pre>
  
  <p>None of them seem to do anything.  How do I clean the boost workspace?</p>