n to measure
<code class="arg">offset</code> from. It defaults to the start of
the file. <code class="arg">Origin</code> must be one of: 

<ul>
<li><code class="keyword">start</code>.........<code class=
"arg">Offset</code> is measured from the start of the file.</li>

<li><code class="keyword">current</code>...<code class=
"arg">Offset</code> is measured from the current position in the
file.</li>

<li><code class="keyword">end</code>...........<code class=
"arg">Offset</code> is measured from the end of t