ugfx/3rdparty/fatfs-0.13/documents/doc/sync.html

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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/sync.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_sync</title>
</head>
<body>
<div class="para func">
<h2>f_sync</h2>
<p>The f_sync function flushes the cached information of a writing file.</p>
<pre>
FRESULT f_sync (
FIL* <span class="arg">fp</span> <span class="c">/* [IN] File object */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameter</h4>
<dl class="par">
<dt>fp</dt>
<dd>Pointer to the open file object to be flushed.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#de">FR_DISK_ERR</a>,
<a href="rc.html#ie">FR_INT_ERR</a>,
<a href="rc.html#io">FR_INVALID_OBJECT</a>,
<a href="rc.html#tm">FR_TIMEOUT</a>
</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The <tt>f_sync</tt> function performs the same process as <tt>f_close</tt> function but the file is left opened and can continue read/write/seek operations to the file. This is suitable for the applications that open files for a long time in write mode, such as data logger. Performing <tt>f_sync</tt> function of periodic or immediataly after <tt>f_write</tt> function can minimize the risk of data loss due to a sudden blackout or an unintentional media removal. For more information, refer to <a href="appnote.html#critical">application note</a>.</p>
<p>However there is no sense in <tt>f_sync</tt> function immediataly before <tt>f_close</tt> function because it performs <tt>f_sync</tt> function in it. In other words, the differnce between those functions is that the file object is invalidated or not.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt>FF_FS_READONLY == 0</tt>.</p>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="close.html">f_close</a></tt>, <a href="appnote.html#critical">Critical section</a></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>