tatic</span> <span class="identifier">optional</span><span class="special">&lt;</span> <span class="keyword">int</span> <span class="special">&gt;</span> <a name="idp43962464-bb"></a><span class="identifier">io_rank</span><span class="special">(</span><span class="special">)</span><span class="special">;</span></pre>
<p>Retrieves the rank of a process that can perform input/output.</p>
<p>This routine returns the rank of a process that can perform input/output via the standard C and C++ I/O facilities. If e