 (usually not the case in builds for unix-like systems).
</p>
<p>For example to read from a file &lsquo;<tt>input.mpeg</tt>&rsquo; with <code>ffmpeg</code>
use the command:
</p><div class="example">
<pre class="example">ffmpeg -i file:input.mpeg output.mpeg
</pre></div>

<p>This protocol accepts the following options:
</p>
<dl compact="compact">
<dt>&lsquo;<samp>truncate</samp>&rsquo;</dt>
<dd><p>Truncate existing files on write, if set to 1. A value of 0 prevents
truncating. Default value is 1.
</p>
</dd>
