"code">open_in_gen mode perm filename</code> opens the named file for reading,
   as described above. The extra arguments
   <code class="code">mode</code> and <code class="code">perm</code> specify the opening mode and file permissions.
   <a href="Pervasives.html#VALopen_in"><code class="code">open_in</code></a> and <a href="Pervasives.html#VALopen_in_bin"><code class="code">open_in_bin</code></a> are special
   cases of this function.<br>
</div>

<pre><span id="VALinput_char"><span class="keyword">val</s