ated, though this is
       probably only useful for textual <code class="command">COPY</code>.  A result
       of zero indicates that the <code class="command">COPY</code> is still in
       progress, but no row is yet available (this is only possible when
       <em class="parameter"><code>async</code></em> is true).  A result of -1 indicates that the
       <code class="command">COPY</code> is done.  A result of -2 indicates that an
       error occurred (consult <a class="xref" href="libpq-status.html#