title: Unable to use dot layout (graphviz as a library)
body: <p>I use graphviz (v2.28.0) as a library in a C++ application and I would like to render graphs using the dot layout. Everything works fine until I call the <strong>gvLayout(_context, _graph, "dot");</strong> function which outputs the following error :</p>
  
  <pre><code> Error: Layout type: "dot" not recognized. Use one of:
  </code></pre>
  
  <p>I use the following library flags when linking :</p>
  
  <pre><code>-lgvc -lgraph -lpathplan -lcdt -lgvplugin_dot_layout
  </code></pre>
  
  <p>Calling dot from the Unix command line works as expected. What am I doing wrong ?</p>