RT1050_FreeRTOS_Hello/middleware/fatfs/documents/doc/chdrive.html

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<title>FatFs - f_chdrive</title>
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<body>
<div class="para func">
<h2>f_chdrive</h2>
<p>The f_chdrive function changes the current drive.</p>
<pre>
FRESULT f_chdrive (
const TCHAR* <span class="arg">path</span> <span class="c">/* [IN] Logical drive number */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>path</dt>
<dd>Specifies the <a href="filename.html">logical drive number</a> to be set as the current drive.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#id">FR_INVALID_DRIVE</a>
</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The <tt>f_chdrive</tt> function changes only the current drive. The initial value of the current drive number is 0. Note that the current drive is retained in a static variable, so that it also affects other tasks that using the file functions.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt><a href="config.html#fs_rpath">FF_FS_RPATH</a> &gt;= 1</tt>.</p>
</div>
<div class="para use">
<h4>Example</h4>
<pre>
<em>f_chdrive</em>("2:"); <span class="c">/* Set drive 2 as current drive */</span>
<em>f_chdrive</em>(""); <span class="c">/* No effect (set current drive as current drive) */</span>
<em>f_chdrive</em>("/flash"); <span class="c">/* Set drive "flash" as current drive (at Unix style volume ID) */</span>
</pre>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="chdir.html">f_chdir</a>, <a href="getcwd.html">f_getcwd</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
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