single volume system and every disk function is re-entered at multiple volume system. Thus the low level disk I/O layer must be always thread-safe when FatFs API is re-entered by two or more tasks.</p>
</div>

<div class="para doc" id="dup">
<h3>Duplicated File Open</h3>
<p>FatFs module does not support the read/write collision control of duplicated open to a file. The duplicated open is permitted only when each of open method to a file is read mode. The duplicated open with one or more write mode to a file