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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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<hr size="2" noshade>
<h4><a name="tag_03_781_01"></a>NAME</h4>
<blockquote>tmpfile - create a temporary file</blockquote>
<h4><a name="tag_03_781_02"></a>SYNOPSIS</h4>
<blockquote class="synopsis">
<p><code><tt>#include &lt;<a href="../basedefs/stdio.h.html">stdio.h</a>&gt;<br>
<br>
FILE *tmpfile(void);<br>
</tt></code></p>
</blockquote>
<h4><a name="tag_03_781_03"></a>DESCRIPTION</h4>
<blockquote>
<div class="box"><sup>[<a href="javascript:open_code('CX')">CX</a>]</sup> <img src="../images/opt-start.gif" alt="[Option Start]"
border="0"> The functionality described on this reference page is aligned with the ISO&nbsp;C standard. Any conflict between the
requirements described here and the ISO&nbsp;C standard is unintentional. This volume of IEEE&nbsp;Std&nbsp;1003.1-2001 defers to
the ISO&nbsp;C standard. <img src="../images/opt-end.gif" alt="[Option End]" border="0"></div>
<p>The <i>tmpfile</i>() function shall create a temporary file and open a corresponding stream. The file shall be automatically
deleted when all references to the file are closed. The file is opened as in <a href="../functions/fopen.html"><i>fopen</i>()</a>
for update (<i>w</i>+).</p>
<p><sup>[<a href="javascript:open_code('CX')">CX</a>]</sup> <img src="../images/opt-start.gif" alt="[Option Start]" border="0"> In
some implementations, a permanent file may be left behind if the process calling <i>tmpfile</i>() is killed while it is processing
a call to <i>tmpfile</i>().</p>
<p>An error message may be written to standard error if the stream cannot be opened. <img src="../images/opt-end.gif" alt=
"[Option End]" border="0"></p>
</blockquote>
<h4><a name="tag_03_781_04"></a>RETURN VALUE</h4>
<blockquote>
<p>Upon successful completion, <i>tmpfile</i>() shall return a pointer to the stream of the file that is created. Otherwise, it
shall return a null pointer <sup>[<a href="javascript:open_code('CX')">CX</a>]</sup> <img src="../images/opt-start.gif" alt=
"[Option Start]" border="0"> &nbsp;and set <i>errno</i> to indicate the error. <img src="../images/opt-end.gif" alt="[Option End]"
border="0"></p>
</blockquote>
<h4><a name="tag_03_781_05"></a>ERRORS</h4>
<blockquote>
<p>The <i>tmpfile</i>() function shall fail if:</p>
<dl compact>
<dt>[EINTR]</dt>
<dd><sup>[<a href="javascript:open_code('CX')">CX</a>]</sup> <img src="../images/opt-start.gif" alt="[Option Start]" border="0"> A
signal was caught during <i>tmpfile</i>(). <img src="../images/opt-end.gif" alt="[Option End]" border="0"></dd>
<dt>[EMFILE]</dt>
<dd><sup>[<a href="javascript:open_code('CX')">CX</a>]</sup> <img src="../images/opt-start.gif" alt="[Option Start]" border="0">
{OPEN_MAX} file descriptors are currently open in the calling process. <img src="../images/opt-end.gif" alt="[Option End]" border=
"0"></dd>
<dt>[ENFILE]</dt>
<dd><sup>[<a href="javascript:open_code('CX')">CX</a>]</sup> <img src="../images/opt-start.gif" alt="[Option Start]" border="0">
The maximum allowable number of files is currently open in the system. <img src="../images/opt-end.gif" alt="[Option End]" border=
"0"></dd>
<dt>[ENOSPC]</dt>
<dd><sup>[<a href="javascript:open_code('CX')">CX</a>]</sup> <img src="../images/opt-start.gif" alt="[Option Start]" border="0">
The directory or file system which would contain the new file cannot be expanded. <img src="../images/opt-end.gif" alt=
"[Option End]" border="0"></dd>
<dt>[EOVERFLOW]</dt>
<dd><sup>[<a href="javascript:open_code('CX')">CX</a>]</sup> <img src="../images/opt-start.gif" alt="[Option Start]" border="0">
The file is a regular file and the size of the file cannot be represented correctly in an object of type <b>off_t</b>. <img src=
"../images/opt-end.gif" alt="[Option End]" border="0"></dd>
</dl>
<p>The <i>tmpfile</i>() function may fail if:</p>
<dl compact>
<dt>[EMFILE]</dt>
<dd><sup>[<a href="javascript:open_code('CX')">CX</a>]</sup> <img src="../images/opt-start.gif" alt="[Option Start]" border="0">
{FOPEN_MAX} streams are currently open in the calling process. <img src="../images/opt-end.gif" alt="[Option End]" border="0"></dd>
<dt>[ENOMEM]</dt>
<dd><sup>[<a href="javascript:open_code('CX')">CX</a>]</sup> <img src="../images/opt-start.gif" alt="[Option Start]" border="0">
Insufficient storage space is available. <img src="../images/opt-end.gif" alt="[Option End]" border="0"></dd>
</dl>
</blockquote>
<hr>
<div class="box"><em>The following sections are informative.</em></div>
<h4><a name="tag_03_781_06"></a>EXAMPLES</h4>
<blockquote>
<h5><a name="tag_03_781_06_01"></a>Creating a Temporary File</h5>
<p>The following example creates a temporary file for update, and returns a pointer to a stream for the created file in the
<i>fp</i> variable.</p>
<pre>
<tt>#include &lt;stdio.h&gt;
...
FILE *fp;
<br>
fp = tmpfile ();
</tt>
</pre>
</blockquote>
<h4><a name="tag_03_781_07"></a>APPLICATION USAGE</h4>
<blockquote>
<p>It should be possible to open at least {TMP_MAX} temporary files during the lifetime of the program (this limit may be shared
with <a href="../functions/tmpnam.html"><i>tmpnam</i>()</a>) and there should be no limit on the number simultaneously open other
than this limit and any limit on the number of open files ( {FOPEN_MAX}).</p>
</blockquote>
<h4><a name="tag_03_781_08"></a>RATIONALE</h4>
<blockquote>
<p>None.</p>
</blockquote>
<h4><a name="tag_03_781_09"></a>FUTURE DIRECTIONS</h4>
<blockquote>
<p>None.</p>
</blockquote>
<h4><a name="tag_03_781_10"></a>SEE ALSO</h4>
<blockquote>
<p><a href="fopen.html"><i>fopen</i>()</a> , <a href="tmpnam.html"><i>tmpnam</i>()</a> , <a href="unlink.html"><i>unlink</i>()</a>
, the Base Definitions volume of IEEE&nbsp;Std&nbsp;1003.1-2001, <a href="../basedefs/stdio.h.html"><i>&lt;stdio.h&gt;</i></a></p>
</blockquote>
<h4><a name="tag_03_781_11"></a>CHANGE HISTORY</h4>
<blockquote>
<p>First released in Issue 1. Derived from Issue 1 of the SVID.</p>
</blockquote>
<h4><a name="tag_03_781_12"></a>Issue 5</h4>
<blockquote>
<p>Large File Summit extensions are added.</p>
<p>The last two paragraphs of the DESCRIPTION were included as APPLICATION USAGE notes in previous issues.</p>
</blockquote>
<h4><a name="tag_03_781_13"></a>Issue 6</h4>
<blockquote>
<p>Extensions beyond the ISO&nbsp;C standard are marked.</p>
<p>The following new requirements on POSIX implementations derive from alignment with the Single UNIX Specification:</p>
<ul>
<li>
<p>In the ERRORS section, the [EOVERFLOW] condition is added. This change is to support large files.</p>
</li>
<li>
<p>The [EMFILE] optional error condition is added.</p>
</li>
</ul>
<p>The APPLICATION USAGE section is added for alignment with the ISO/IEC&nbsp;9899:1999 standard.</p>
</blockquote>
<div class="box"><em>End of informative text.</em></div>
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