[z180-stamp.git] / fatfs / doc / en / readdir.html

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">\r
<html lang="en">\r
<head>\r
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">\r
<meta http-equiv="Content-Style-Type" content="text/css">\r
<link rel="up" title="FatFs" href="../00index_e.html">\r
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/readdir.html">\r
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<title>FatFs - f_readdir</title>\r
</head>\r
\r
<body>\r
\r
<div class="para func">\r
<h2>f_readdir</h2>\r
<p>The f_readdir function reads an item of the directory.</p>\r
<pre>\r
FRESULT f_readdir (\r
  DIR* <span class="arg">dp</span>,      <span class="c">/* [IN] Directory object */</span>\r
  FILINFO* <span class="arg">fno</span>  <span class="c">/* [OUT] File information structure */</span>\r
);\r
</pre>\r
</div>\r
\r
<div class="para arg">\r
<h4>Parameters</h4>\r
<dl class="par">\r
<dt>dp</dt>\r
<dd>Pointer to the open directory object or null pointer.</dd>\r
<dt>fno</dt>\r
<dd>Pointer to the <a href="sfileinfo.html">file information structure</a> to store the information about read item.</dd>\r
</dl>\r
</div>\r
\r
\r
<div class="para ret">\r
<h4>Return Values</h4>\r
<p>\r
<a href="rc.html#ok">FR_OK</a>,\r
<a href="rc.html#de">FR_DISK_ERR</a>,\r
<a href="rc.html#ie">FR_INT_ERR</a>,\r
<a href="rc.html#io">FR_INVALID_OBJECT</a>,\r
<a href="rc.html#tm">FR_TIMEOUT</a>,\r
<a href="rc.html#nc">FR_NOT_ENOUGH_CORE</a>\r
</p>\r
</div>\r
\r
\r
<div class="para desc">\r
<h4>Description</h4>\r
<p>The <tt>f_readdir</tt> function reads a directory item, informations about the object. All items in the directory can be read in sequence by <tt>f_readdir</tt> function calls. Dot entries (<tt>"."</tt> and <tt>".."</tt>) in the sub-directory are filtered out and they will never appear in the read items. When all directory items have been read and no item to read, a nul 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>\r
<p>When support of long file name (LFN) is enabled, a member <tt>altname[]</tt> is defined in the file information structure to store the short file name of the object. In case of the some conditions listed below, short file name is stored into the <tt>fname[]</tt> and <tt>altname[]</tt> has a null string.</p>\r
<ul>\r
<li>The item has no long file name. (Not the case at exFAT volume)</li>\r
<li>Setting of <tt>_MAX_LFN</tt> is insufficient for the long file name. (Not the case at <tt>_MAX_LFN == 255</tt>)</li>\r
<li>The long file name contains any character not allowed in ANSI/OEM code. (Not the case at <tt>_LFN_UNICODE == 1</tt>)</li>\r
</ul>\r
<p>There is a problem on reading a directory of exFAT volume. The exFAT does not support short file name. This means no name can be returned on the condition above. If it is the case, a "?" is returned as file name to indicate that the object is not accessible. To avoid this problem, configure FatFs <tt>_LFN_UNICODE = 1</tt> and <tt>_MAX_LFN = 255</tt> to support the full feature of LFN specification.</p>\r
</div>\r
\r
\r
<div class="para comp">\r
<h4>QuickInfo</h4>\r
<p>Available when <tt>_FS_MINIMIZE &lt;= 1</tt>.</p>\r
</div>\r
\r
\r
<div class="para use">\r
<h4>Sample Code</h4>\r
<pre>\r
FRESULT scan_files (\r
    char* path        <span class="c">/* Start node to be scanned (***also used as work area***) */</span>\r
)\r
{\r
    FRESULT res;\r
    DIR dir;\r
    UINT i;\r
    static FILINFO fno;\r
\r
\r
    res = f_opendir(&amp;dir, path);                       <span class="c">/* Open the directory */</span>\r
    if (res == FR_OK) {\r
        for (;;) {\r
            res = f_readdir(&amp;dir, &amp;fno);                   <span class="c">/* Read a directory item */</span>\r
            if (res != FR_OK || fno.fname[0] == 0) break;  <span class="c">/* Break on error or end of dir */</span>\r
            if (fno.fattrib &amp; AM_DIR) {                    <span class="c">/* It is a directory */</span>\r
                i = strlen(path);\r
                sprintf(&amp;path[i], "/%s", fno.fname);\r
                res = scan_files(path);                    <span class="c">/* Enter the directory */</span>\r
                if (res != FR_OK) break;\r
                path[i] = 0;\r
            } else {                                       <span class="c">/* It is a file. */</span>\r
                printf("%s/%s\n", path, fno.fname);\r
            }\r
        }\r
        f_closedir(&amp;dir)\r
    }\r
\r
    return res;\r
}\r
\r
\r
int main (void)\r
{\r
    FATFS fs;\r
    FRESULT res;\r
    char buff[256];\r
\r
\r
    res = f_mount(&amp;fs, "", 1);\r
    if (res == FR_OK) {\r
        strcpy(buff, "/");\r
        res = scan_files(buff);\r
    }\r
\r
    return res;\r
}\r
</pre>\r
</div>\r
\r
\r
<div class="para ref">\r
<h4>See Also</h4>\r
<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>\r
</div>\r
\r
<p class="foot"><a href="../00index_e.html">Return</a></p>\r
</body>\r
</html>\r
Commit	Line	Data
53668523 L	1	<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">\r
	2	<html lang="en">\r
	3	<head>\r
	4	<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">\r
	5	<meta http-equiv="Content-Style-Type" content="text/css">\r
	6	<link rel="up" title="FatFs" href="../00index_e.html">\r
	7	<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/readdir.html">\r
	8	<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">\r
	9	<title>FatFs - f_readdir</title>\r
	10	</head>\r
	11	\r
	12	<body>\r
	13	\r
	14	<div class="para func">\r
	15	<h2>f_readdir</h2>\r
70702af1	16	<p>The f_readdir function reads an item of the directory.</p>\r
53668523 L	17	<pre>\r
	18	FRESULT f_readdir (\r
	19	DIR* <span class="arg">dp</span>, <span class="c">/* [IN] Directory object */</span>\r
	20	FILINFO* <span class="arg">fno</span> <span class="c">/* [OUT] File information structure */</span>\r
	21	);\r
	22	</pre>\r
	23	</div>\r
	24	\r
	25	<div class="para arg">\r
	26	<h4>Parameters</h4>\r
	27	<dl class="par">\r
	28	<dt>dp</dt>\r
70702af1	29	<dd>Pointer to the open directory object or null pointer.</dd>\r
53668523	30	<dt>fno</dt>\r
70702af1	31	<dd>Pointer to the <a href="sfileinfo.html">file information structure</a> to store the information about read item.</dd>\r
53668523 L	32	</dl>\r
	33	</div>\r
	34	\r
	35	\r
	36	<div class="para ret">\r
	37	<h4>Return Values</h4>\r
	38	<p>\r
	39	<a href="rc.html#ok">FR_OK</a>,\r
	40	<a href="rc.html#de">FR_DISK_ERR</a>,\r
	41	<a href="rc.html#ie">FR_INT_ERR</a>,\r
53668523 L	42	<a href="rc.html#io">FR_INVALID_OBJECT</a>,\r
	43	<a href="rc.html#tm">FR_TIMEOUT</a>,\r
	44	<a href="rc.html#nc">FR_NOT_ENOUGH_CORE</a>\r
	45	</p>\r
	46	</div>\r
	47	\r
	48	\r
	49	<div class="para desc">\r
	50	<h4>Description</h4>\r
70702af1 L	51	<p>The <tt>f_readdir</tt> function reads a directory item, informations about the object. All items in the directory can be read in sequence by <tt>f_readdir</tt> function calls. Dot entries (<tt>"."</tt> and <tt>".."</tt>) in the sub-directory are filtered out and they will never appear in the read items. When all directory items have been read and no item to read, a nul string is stored into the <tt>fno->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>\r
70702af1 L	52	<p>When support of long file name (LFN) is enabled, a member <tt>altname[]</tt> is defined in the file information structure to store the short file name of the object. In case of the some conditions listed below, short file name is stored into the <tt>fname[]</tt> and <tt>altname[]</tt> has a null string.</p>\r
53668523	53	<ul>\r
70702af1 L	54	<li>The item has no long file name. (Not the case at exFAT volume)</li>\r
	55	<li>Setting of <tt>_MAX_LFN</tt> is insufficient for the long file name. (Not the case at <tt>_MAX_LFN == 255</tt>)</li>\r
	56	<li>The long file name contains any character not allowed in ANSI/OEM code. (Not the case at <tt>_LFN_UNICODE == 1</tt>)</li>\r
53668523	57	</ul>\r
70702af1	58	<p>There is a problem on reading a directory of exFAT volume. The exFAT does not support short file name. This means no name can be returned on the condition above. If it is the case, a "?" is returned as file name to indicate that the object is not accessible. To avoid this problem, configure FatFs <tt>_LFN_UNICODE = 1</tt> and <tt>_MAX_LFN = 255</tt> to support the full feature of LFN specification.</p>\r
53668523 L	59	</div>\r
	60	\r
	61	\r
	62	<div class="para comp">\r
	63	<h4>QuickInfo</h4>\r
	64	<p>Available when <tt>_FS_MINIMIZE <= 1</tt>.</p>\r
	65	</div>\r
	66	\r
	67	\r
	68	<div class="para use">\r
	69	<h4>Sample Code</h4>\r
	70	<pre>\r
	71	FRESULT scan_files (\r
70702af1	72	char* path <span class="c">/* Start node to be scanned (*also used as work area) /</span>\r
53668523 L	73	)\r
	74	{\r
	75	FRESULT res;\r
53668523	76	DIR dir;\r
70702af1 L	77	UINT i;\r
70702af1 L	78	static FILINFO fno;\r
53668523 L	79	\r
	80	\r
	81	res = f_opendir(&dir, path); <span class="c">/* Open the directory */</span>\r
	82	if (res == FR_OK) {\r
53668523 L	83	for (;;) {\r
	84	res = f_readdir(&dir, &fno); <span class="c">/* Read a directory item */</span>\r
	85	if (res != FR_OK \|\| fno.fname[0] == 0) break; <span class="c">/* Break on error or end of dir */</span>\r
53668523	86	if (fno.fattrib & AM_DIR) { <span class="c">/* It is a directory */</span>\r
70702af1 L	87	i = strlen(path);\r
	88	sprintf(&path[i], "/%s", fno.fname);\r
	89	res = scan_files(path); <span class="c">/* Enter the directory */</span>\r
7b78a5a2	90	if (res != FR_OK) break;\r
70702af1	91	path[i] = 0;\r
53668523	92	} else { <span class="c">/* It is a file. */</span>\r
70702af1	93	printf("%s/%s\n", path, fno.fname);\r
53668523 L	94	}\r
	95	}\r
	96	f_closedir(&dir)\r
	97	}\r
	98	\r
	99	return res;\r
	100	}\r
70702af1 L	101	\r
	102	\r
	103	int main (void)\r
	104	{\r
	105	FATFS fs;\r
	106	FRESULT res;\r
	107	char buff[256];\r
	108	\r
	109	\r
	110	res = f_mount(&fs, "", 1);\r
	111	if (res == FR_OK) {\r
	112	strcpy(buff, "/");\r
	113	res = scan_files(buff);\r
	114	}\r
	115	\r
	116	return res;\r
	117	}\r
53668523 L	118	</pre>\r
	119	</div>\r
	120	\r
	121	\r
	122	<div class="para ref">\r
	123	<h4>See Also</h4>\r
	124	<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>\r
	125	</div>\r
	126	\r
	127	<p class="foot"><a href="../00index_e.html">Return</a></p>\r
	128	</body>\r
	129	</html>\r