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<section id="tmpfs">
<h1>TMPFS<a class="headerlink" href="#tmpfs" title="Permalink to this heading"></a></h1>
<p>NuttX TMPFS file system is a tiny dyamic RAM based file system.</p>
<p>It can be enabled by adding <code class="docutils literal notranslate"><span class="pre">CONFIG_FS_TMPFS=y</span></code> to the configuration at build time.</p>
<p>At runtime, simply use <code class="docutils literal notranslate"><span class="pre">mount</span> <span class="pre">-t</span> <span class="pre">tmpfs</span> <span class="pre">/tmp</span></code> to have a <code class="docutils literal notranslate"><span class="pre">/tmp</span></code> folder backed by TMPFS, then files and folders can be created under that folder.</p>
<p>Be aware that TMPFS is backed by kernel memory thus don’t expect to store big files on it and its size is limited by free kernel memory.</p>
<p>We can watch the size of TMPFS with <code class="docutils literal notranslate"><span class="pre">df</span> <span class="pre">-h</span></code> command, especially you can see the <code class="docutils literal notranslate"><span class="pre">Size</span></code> column of TMPFS changes when files are added or removed in the TMPFS folder. Changes in TMPFS size is always reflected by reverse changes of free kernel memory size.</p>
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