title: What does first parameter in ecl_init_module do?
body: <p>According to some parts of ECL manual, necessary part of the library (that has been compiled by lisp) initialisation in C program is performing its initialisation as:</p>
  <pre><code>ecl_init_module(NULL, init_func_for_library);
  </code></pre>
  <p>In all examples provided first parameter is NULL.</p>
  <p>What other values can it take and to what end? Certainly the parameter itself should have some meaning.</p>
  <p>NB. In other parts of the manual, for performing initialisation, it is recommended to use read_VV instead. What does that do?</p>