fatfs/doc/en/sync.html

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   9 <title>FatFs - f_sync</title>
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  13
  14 <div class="para func">
  15 <h2>f_sync</h2>
  16 <p>The f_sync function flushes the cached information of a writing file.</p>
  17 <pre>
  18 FRESULT f_sync (
  19   FIL* <span class="arg">fp</span>     <span class="c">/* [IN] File object */</span>
  20 );
  21 </pre>
  22 </div>
  23
  24 <div class="para arg">
  25 <h4>Parameter</h4>
  26 <dl class="par">
  27 <dt>fp</dt>
  28 <dd>Pointer to the open file object to be flushed.</dd>
  29 </dl>
  30 </div>
  31
  32
  33 <div class="para ret">
  34 <h4>Return Values</h4>
  35 <p>
  36 <a href="rc.html#ok">FR_OK</a>,
  37 <a href="rc.html#de">FR_DISK_ERR</a>,
  38 <a href="rc.html#ie">FR_INT_ERR</a>,
  39 <a href="rc.html#nr">FR_NOT_READY</a>,
  40 <a href="rc.html#io">FR_INVALID_OBJECT</a>,
  41 <a href="rc.html#tm">FR_TIMEOUT</a>
  42 </p>
  43 </div>
  44
  45
  46 <div class="para desc">
  47 <h4>Description</h4>
  48 <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>
  49 <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>
  50 </div>
  51
  52
  53 <div class="para comp">
  54 <h4>QuickInfo</h4>
  55 <p>Available when <tt>_FS_READONLY == 0</tt>.</p>
  56 </div>
  57
  58
  59 <div class="para ref">
  60 <h4>See Also</h4>
  61 <p><tt><a href="close.html">f_close</a></tt></p>
  62 </div>
  63
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