ibm-information-center/dist/eclipse/plugins/i5OS.ic.apis_5.4.0.1/rewinddi.htm

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<title>rewinddir()--Reset Directory Stream to Beginning</title>
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<h2>rewinddir()--Reset Directory Stream to Beginning</h2>
<div class="box" style="width: 60%;">
<br>
&nbsp;&nbsp;Syntax<br>
<pre>
#include &lt;sys/types.h&gt;
#include &lt;dirent.h&gt;
void rewinddir(DIR <em>*dirp</em>);
</pre>
&nbsp;&nbsp;Service Program Name: QP0LLIB1<br>
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<br>
&nbsp;&nbsp;Default Public Authority: *USE<br>
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&nbsp;&nbsp;Threadsafe: Yes<br>
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<p>The <strong>rewinddir()</strong> function "rewinds" the position of an open
directory stream to the beginning. <em>dirp</em> points to a <samp>DIR</samp>
associated with an open directory stream.</p>
<p>The next call to <strong>readdir()</strong> reads the first entry in the
directory. If the contents of the directory have changed since the directory
was opened and <strong>rewinddir()</strong> is called, subsequent calls to
<strong>readdir()</strong> read the changed contents.</p>
<br>
<h3>Parameters</h3>
<dl>
<dt><strong><em>dirp</em></strong></dt>
<dd>(Input) A pointer to a <samp>DIR</samp> that refers to the open directory
stream to be rewound. This pointer is returned by the <samp>opendir()</samp>
function.</dd>
</dl>
<br>
<h3>Authorities</h3>
<p>No authorization is required. Authorization is verified during <strong>
opendir()</strong>.</p>
<br>
<h3>Return Value</h3>
<p>None.</p>
<br>
<h3>Error Conditions</h3>
<p>None.</p>
<br>
<h3>Error Messages</h3>
<p>The following messages may be sent from this function:</p>
<table width="100%" cellpadding="5">
<tr>
<th align="left" valign="top">Message ID</th>
<th align="left" valign="top">Error Message Text</th>
</tr>
<tr>
<td width="15%" valign="top">CPE3418 E</td>
<td width="85%" valign="top">Possible APAR condition or hardware failure.</td>
</tr>
<tr>
<td valign="top">CPF1F05 E</td>
<td valign="top">Directory handle not valid.</td>
</tr>
<tr>
<td valign="top">CPF3CF2 E</td>
<td valign="top">Error(s) occurred during running of &amp;1 API.</td>
</tr>
</table>
<br>
<br>
<h3><a name="USAGE_NOTES">Usage Notes</a></h3>
<ol type="1">
<li>If the <em>dirp</em> argument passed to <strong>rewinddir()</strong> does
not refer to an open directory, unexpected results could occur.<br>
</li>
<li>Files that are added to the directory after <strong>opendir()</strong> or
<strong>rewinddir()</strong> may not be returned on calls to <strong>
readdir()</strong>.</li>
</ol>
<br>
<h3>Related Information</h3>
<ul>
<li>The &lt;<strong>sys/types.h</strong>&gt; file (see <a href="unix13.htm">
Header Files for UNIX-Type Functions</a>)<br>
</li>
<li>The &lt;<strong>dirent.h</strong>&gt; file (see <a href="unix13.htm">Header
Files for UNIX-Type Functions</a>)<br>
</li>
<li><a href="opendir.htm">opendir()</a>--Open Directory<br>
</li>
<li><a href="readdir.htm">readdir()</a>--Read Directory Entry<br>
</li>
<li><a href="closedir.htm">closedir()</a>--Close Directory</li>
</ul>
<br>
<h3>Example</h3>
<p>See <a href="../apiref/aboutapis.htm#codedisclaimer">Code disclaimer information</a>
for information pertaining to code examples.</p>
<p>The following example produces the contents of a directory by opening it,
rewinding it, and closing it:</p>
<pre>
#include &lt;sys/types.h&gt;
#include &lt;dirent.h&gt;
#include &lt;errno.h&gt;
#include &lt;stdio.h&gt;
main() {
DIR *dir;
struct dirent *entry;
if ((dir = opendir("/")) == NULL)
perror("opendir() error");
else {
puts("contents of root:");
while ((entry = readdir(dir)) != NULL)
printf("%s ", entry-&gt;d_name);
rewinddir(dir);
puts("");
while ((entry = readdir(dir)) != NULL)
printf("%s ", entry-&gt;d_name);
closedir(dir);
puts("");
}
}
</pre>
<p><strong>Output:</strong></p>
<pre>
contents of root:
. .. QSYS.LIB QDLS QOpenSys QOPT home
. .. QSYS.LIB QDLS QOpenSys QOPT home newdir
</pre>
<br>
<hr>
API introduced: V3R1
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