rotek
/
module_universal_io


			
							123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124
							<!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/readdir.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_readdir</title>
</head>

<body>

<div class="para func">
<h2>f_readdir</h2>
<p>The f_readdir function reads directory entries.</p>
<pre>
FRESULT f_readdir (
  DIR* <span class="arg">dp</span>,      <span class="c">/* [IN] Directory object */</span>
  FILINFO* <span class="arg">fno</span>  <span class="c">/* [OUT] File information structure */</span>
);
</pre>
</div>

<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>dp</dt>
<dd>Pointer to the directory object opened by <tt>f_opendir</tt> function.</dd>
<dt>fno</dt>
<dd>Pointer to the file information structure to store the information about read item.</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>,
<a href="rc.html#nc">FR_NOT_ENOUGH_CORE</a>
</p>
</div>


<div class="para desc">
<h4>Description</h4>
<p>The <tt>f_readdir</tt> function reads directory items, informations about file and directory, in sequence. All items in the directory can be read by calling <tt>f_readdir</tt> function repeatedly. When relative path feature is enabled (<tt><a href="config.html#fs_rpath">_FS_RPATH</a> &gt;= 1</tt>), dot entries (<tt>"."</tt> and <tt>".."</tt>) are not filtered out and they will appear in the read items. When all directory items have been read and no item to read, a null string is stored into the <tt>fno-&gt;fname[]</tt> without any error. When a null pointer is given to the <tt class="arg">fno</tt>, the read index of the directory object is rewinded.</p>
<p>When LFN feature is enabled, <tt>lfname</tt> and <tt>lfsize</tt> in the file information structure must be initialized with valid value prior to use it. The <tt>lfname</tt> is a pointer to the LFN read buffer. The <tt>lfsize</tt> is size of the LFN read buffer in unit of <tt>TCHAR</tt>. If the LFN is not needed, set a null pointer to the <tt>lfname</tt> and the LFN is not returned. A null string will be returned into the LFN read buffer in case of following conditions.</p>
<ul>
<li>The directory item has no LFN information.</li>
<li>Either the size of read buffer or LFN working buffer is insufficient for the LFN.</li>
<li>The LFN contains any Unicode character that cannot be converted to OEM code. (not the case at Unicode API cfg.)</li>
</ul>
<p>When the directory item has no LFN, lower case characters can be contained in the <tt>fname[]</tt>.</p>
</div>


<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt>_FS_MINIMIZE &lt;= 1</tt>.</p>
</div>


<div class="para use">
<h4>Sample Code</h4>
<pre>
FRESULT scan_files (
    char* path        <span class="c">/* Start node to be scanned (also used as work area) */</span>
)
{
    FRESULT res;
    FILINFO fno;
    DIR dir;
    int i;
    char *fn;   <span class="c">/* This function assumes non-Unicode configuration */</span>
<span class="k">#if</span> _USE_LFN
    static char lfn[_MAX_LFN + 1];   <span class="c">/* Buffer to store the LFN */</span>
    fno.lfname = lfn;
    fno.lfsize = sizeof lfn;
<span class="k">#endif</span>


    res = f_opendir(&amp;dir, path);                       <span class="c">/* Open the directory */</span>
    if (res == FR_OK) {
        i = strlen(path);
        for (;;) {
            res = f_readdir(&amp;dir, &amp;fno);                   <span class="c">/* Read a directory item */</span>
            if (res != FR_OK || fno.fname[0] == 0) break;  <span class="c">/* Break on error or end of dir */</span>
            if (fno.fname[0] == '.') continue;             <span class="c">/* Ignore dot entry */</span>
<span class="k">#if</span> _USE_LFN
            fn = *fno.lfname ? fno.lfname : fno.fname;
<span class="k">#else</span>
            fn = fno.fname;
<span class="k">#endif</span>
            if (fno.fattrib &amp; AM_DIR) {                    <span class="c">/* It is a directory */</span>
                sprintf(&amp;path[i], "/%s", fn);
                res = scan_files(path);
                path[i] = 0;
                if (res != FR_OK) break;
            } else {                                       <span class="c">/* It is a file. */</span>
                printf("%s/%s\n", path, fn);
            }
        }
        f_closedir(&amp;dir)
    }

    return res;
}
</pre>
</div>


<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="opendir.html">f_opendir</a>, <a href="closedir.html">f_closedir</a>, <a href="stat.html">f_stat</a>, <a href="sfileinfo.html">FILINFO</a>, <a href="sdir.html">DIR</a></tt></p>
</div>

<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>