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<center><font size="2">The Open Group Base Specifications Issue 6<br>
IEEE Std 1003.1-2001<br>
Copyright &copy; 2001 The IEEE and The Open Group, All Rights reserved.</font></center>
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<h4><a name="tag_13_29_01"></a>NAME</h4>
<blockquote>ndbm.h - definitions for ndbm database operations</blockquote>
<h4><a name="tag_13_29_02"></a>SYNOPSIS</h4>
<blockquote class="synopsis">
<div class="box"><tt><sup>[<a href="javascript:open_code('XSI')">XSI</a>]</sup> <img src="../images/opt-start.gif" alt=
"[Option Start]" border="0"> #include &lt;ndbm.h&gt; <img src="../images/opt-end.gif" alt="[Option End]" border="0"></tt></div>
</blockquote>
<h4><a name="tag_13_29_03"></a>DESCRIPTION</h4>
<blockquote>
<p>The <i>&lt;ndbm.h&gt;</i> header shall define the <b>datum</b> type as a structure that includes at least the following
members:</p>
<pre>
<tt>void *dptr </tt> A pointer to the application's data. <tt>
size_t dsize</tt> The size of the object pointed to by <i>dptr.</i> <tt>
</tt>
</pre>
<p>The <b>size_t</b> type shall be defined as described in <a href="stddef.h.html"><i>&lt;stddef.h&gt;</i></a> .</p>
<p>The <i>&lt;ndbm.h&gt;</i> header shall define the <b>DBM</b> type.</p>
<p>The following constants shall be defined as possible values for the <i>store_mode</i> argument to <a href=
"../functions/dbm_store.html"><i>dbm_store</i>()</a>:</p>
<dl compact>
<dt>DBM_INSERT</dt>
<dd>Insertion of new entries only.</dd>
<dt>DBM_REPLACE</dt>
<dd>Allow replacing existing entries.</dd>
</dl>
<p>The following shall be declared as functions and may also be defined as macros. Function prototypes shall be provided.</p>
<pre>
<tt>int dbm_clearerr(DBM *);
void dbm_close(DBM *);
int dbm_delete(DBM *, datum);
int dbm_error(DBM *);
datum dbm_fetch(DBM *, datum);
datum dbm_firstkey(DBM *);
datum dbm_nextkey(DBM *);
DBM *dbm_open(const char *, int, mode_t);
int dbm_store(DBM *, datum, datum, int);
</tt>
</pre>
<p>The <b>mode_t</b> type shall be defined through <b>typedef</b> as described in <a href=
"sys/types.h.html"><i>&lt;sys/types.h&gt;</i></a> .</p>
</blockquote>
<hr>
<div class="box"><em>The following sections are informative.</em></div>
<h4><a name="tag_13_29_04"></a>APPLICATION USAGE</h4>
<blockquote>
<p>None.</p>
</blockquote>
<h4><a name="tag_13_29_05"></a>RATIONALE</h4>
<blockquote>
<p>None.</p>
</blockquote>
<h4><a name="tag_13_29_06"></a>FUTURE DIRECTIONS</h4>
<blockquote>
<p>None.</p>
</blockquote>
<h4><a name="tag_13_29_07"></a>SEE ALSO</h4>
<blockquote>
<p><a href="stddef.h.html"><i>&lt;stddef.h&gt;</i></a> , <a href="sys/types.h.html"><i>&lt;sys/types.h&gt;</i></a> , the System
Interfaces volume of IEEE&nbsp;Std&nbsp;1003.1-2001, <a href="../functions/dbm_clearerr.html"><i>dbm_clearerr</i>()</a></p>
</blockquote>
<h4><a name="tag_13_29_08"></a>CHANGE HISTORY</h4>
<blockquote>
<p>First released in Issue 4, Version 2.</p>
</blockquote>
<h4><a name="tag_13_29_09"></a>Issue 5</h4>
<blockquote>
<p>References to the definitions of <b>size_t</b> and <b>mode_t</b> are added to the DESCRIPTION.</p>
</blockquote>
<div class="box"><em>End of informative text.</em></div>
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