title: Existing threadpool C implementation
body: <p>What open-source implementation(s) in C for a pthreads thread pool would you recommend ?</p>
  
  <p>Additional points if this implementation is :</p>
  
  <ul>
  <li>Light-weight: glib, APR, NSPR and others come with a big buy-in, I'd rather have just 2 files (header and implementation).</li>
  <li>Tested on several platforms (Linux, BSD, Mac OS X, etc.).</li>
  <li>Still maintained.</li>
  </ul>