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<pre>
<span class="headline">TMPNAM(3P)                POSIX Programmer's Manual               TMPNAM(3P)</span>
</pre>
<h2><a id="PROLOG" href="tmpnam.3p.html#PROLOG"></a>PROLOG  &nbsp; &nbsp; &nbsp; &nbsp; <a href="tmpnam.3p.html#top_of_page"><span class="top-link">top</span></a></h2><pre>
       This manual page is part of the POSIX Programmer's Manual.  The Linux
       implementation of this interface may differ (consult the
       corresponding Linux manual page for details of Linux behavior), or
       the interface may not be implemented on Linux.
</pre>
<h2><a id="NAME" href="tmpnam.3p.html#NAME"></a>NAME  &nbsp; &nbsp; &nbsp; &nbsp; <a href="tmpnam.3p.html#top_of_page"><span class="top-link">top</span></a></h2><pre>
       tmpnam — create a name for a temporary file
</pre>
<h2><a id="SYNOPSIS" href="tmpnam.3p.html#SYNOPSIS"></a>SYNOPSIS  &nbsp; &nbsp; &nbsp; &nbsp; <a href="tmpnam.3p.html#top_of_page"><span class="top-link">top</span></a></h2><pre>
       #include &lt;stdio.h&gt;

       char *tmpnam(char *<i>s</i>);
</pre>
<h2><a id="DESCRIPTION" href="tmpnam.3p.html#DESCRIPTION"></a>DESCRIPTION  &nbsp; &nbsp; &nbsp; &nbsp; <a href="tmpnam.3p.html#top_of_page"><span class="top-link">top</span></a></h2><pre>
       The functionality described on this reference page is aligned with
       the ISO C standard. Any conflict between the requirements described
       here and the ISO C standard is unintentional. This volume of
       POSIX.1‐2008 defers to the ISO C standard.

       The <i>tmpnam</i>() function shall generate a string that is a valid
       pathname that does not name an existing file. The function is
       potentially capable of generating {TMP_MAX} different strings, but
       any or all of them may already be in use by existing files and thus
       not be suitable return values.

       The <i>tmpnam</i>() function generates a different string each time it is
       called from the same process, up to {TMP_MAX} times. If it is called
       more than {TMP_MAX} times, the behavior is implementation-defined.

       The implementation shall behave as if no function defined in this
       volume of POSIX.1‐2008, except <i>tempnam</i>(), calls <i>tmpnam</i>().

       The <i>tmpnam</i>() function need not be thread-safe if called with a NULL
       parameter.
</pre>
<h2><a id="RETURN_VALUE" href="tmpnam.3p.html#RETURN_VALUE"></a>RETURN VALUE  &nbsp; &nbsp; &nbsp; &nbsp; <a href="tmpnam.3p.html#top_of_page"><span class="top-link">top</span></a></h2><pre>
       Upon successful completion, <i>tmpnam</i>() shall return a pointer to a
       string. If no suitable string can be generated, the <i>tmpnam</i>() function
       shall return a null pointer.

       If the argument <i>s</i> is a null pointer, <i>tmpnam</i>() shall leave its result
       in an internal static object and return a pointer to that object.
       Subsequent calls to <i>tmpnam</i>() may modify the same object. If the
       argument <i>s</i> is not a null pointer, it is presumed to point to an array
       of at least L_tmpnam <b>char</b>s; <i>tmpnam</i>() shall write its result in that
       array and shall return the argument as its value.
</pre>
<h2><a id="ERRORS" href="tmpnam.3p.html#ERRORS"></a>ERRORS  &nbsp; &nbsp; &nbsp; &nbsp; <a href="tmpnam.3p.html#top_of_page"><span class="top-link">top</span></a></h2><pre>
       No errors are defined.

       <i>The following sections are informative.</i>
</pre>
<h2><a id="EXAMPLES" href="tmpnam.3p.html#EXAMPLES"></a>EXAMPLES  &nbsp; &nbsp; &nbsp; &nbsp; <a href="tmpnam.3p.html#top_of_page"><span class="top-link">top</span></a></h2><pre>
   <b>Generating a Pathname</b>
       The following example generates a unique pathname and stores it in
       the array pointed to by <i>ptr</i>.

           <b>#include &lt;stdio.h&gt;</b>
           <b>...</b>
           <b>char pathname[L_tmpnam+1];</b>
           <b>char *ptr;</b>

           ptr = tmpnam(pathname);
</pre>
<h2><a id="APPLICATION_USAGE" href="tmpnam.3p.html#APPLICATION_USAGE"></a>APPLICATION USAGE  &nbsp; &nbsp; &nbsp; &nbsp; <a href="tmpnam.3p.html#top_of_page"><span class="top-link">top</span></a></h2><pre>
       This function only creates pathnames. It is the application's
       responsibility to create and remove the files.

       Between the time a pathname is created and the file is opened, it is
       possible for some other process to create a file with the same name.
       Applications may find <i>tmpfile</i>() more useful.

       Applications should use the <i>tmpfile</i>(), <i>mkstemp</i>(), or <i>mkdtemp</i>()
       functions instead of the obsolescent <i>tmpnam</i>() function.
</pre>
<h2><a id="RATIONALE" href="tmpnam.3p.html#RATIONALE"></a>RATIONALE  &nbsp; &nbsp; &nbsp; &nbsp; <a href="tmpnam.3p.html#top_of_page"><span class="top-link">top</span></a></h2><pre>
       None.
</pre>
<h2><a id="FUTURE_DIRECTIONS" href="tmpnam.3p.html#FUTURE_DIRECTIONS"></a>FUTURE DIRECTIONS  &nbsp; &nbsp; &nbsp; &nbsp; <a href="tmpnam.3p.html#top_of_page"><span class="top-link">top</span></a></h2><pre>
       The <i>tmpnam</i>() function may be removed in a future version.
</pre>
<h2><a id="SEE_ALSO" href="tmpnam.3p.html#SEE_ALSO"></a>SEE ALSO  &nbsp; &nbsp; &nbsp; &nbsp; <a href="tmpnam.3p.html#top_of_page"><span class="top-link">top</span></a></h2><pre>
       <a href="fopen.3p.html">fopen(3p)</a>, <a href="open.3p.html">open(3p)</a>, <a href="mkdtemp.3p.html">mkdtemp(3p)</a>, <a href="tempnam.3p.html">tempnam(3p)</a>, <a href="tmpfile.3p.html">tmpfile(3p)</a>,
       <a href="unlink.3p.html">unlink(3p)</a>

       The Base Definitions volume of POSIX.1‐2008, <a href="../man0/stdio.h.0p.html">stdio.h(0p)</a>
</pre>
<h2><a id="COPYRIGHT" href="tmpnam.3p.html#COPYRIGHT"></a>COPYRIGHT  &nbsp; &nbsp; &nbsp; &nbsp; <a href="tmpnam.3p.html#top_of_page"><span class="top-link">top</span></a></h2><pre>
       Portions of this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1, 2013 Edition, Standard for Information
       Technology -- Portable Operating System Interface (POSIX), The Open
       Group Base Specifications Issue 7, Copyright (C) 2013 by the
       Institute of Electrical and Electronics Engineers, Inc and The Open
       Group.  (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1
       applied.) In the event of any discrepancy between this version and
       the original IEEE and The Open Group Standard, the original IEEE and
       The Open Group Standard is the referee document. The original
       Standard can be obtained online at <a href="http://www.unix.org/online.html">http://www.unix.org/online.html</a> .

       Any typographical or formatting errors that appear in this page are
       most likely to have been introduced during the conversion of the
       source files to man page format. To report such errors, see
       <a href="https://www.kernel.org/doc/man-pages/reporting_bugs.html">https://www.kernel.org/doc/man-pages/reporting_bugs.html</a> .

<span class="footline">IEEE/The Open Group                 2013                          TMPNAM(3P)</span>
</pre>

<hr class="end-man-text" />
<p>Pages that refer to this page: 
    <a href="../man0/stdio.h.0p.html">stdio.h(0p)</a>,&nbsp; 
    <a href="mkdtemp.3p.html">mkdtemp(3p)</a>,&nbsp; 
    <a href="tempnam.3p.html">tempnam(3p)</a>,&nbsp; 
    <a href="tmpfile.3p.html">tmpfile(3p)</a>
</p>
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