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<a href="strdup.3p.html#PROLOG">PROLOG</a> | <a href="strdup.3p.html#NAME">NAME</a> | <a href="strdup.3p.html#SYNOPSIS">SYNOPSIS</a> | <a href="strdup.3p.html#DESCRIPTION">DESCRIPTION</a> | <a href="strdup.3p.html#RETURN_VALUE">RETURN&nbsp;VALUE</a> | <a href="strdup.3p.html#ERRORS">ERRORS</a> | <a href="strdup.3p.html#EXAMPLES">EXAMPLES</a> | <a href="strdup.3p.html#APPLICATION_USAGE">APPLICATION&nbsp;USAGE</a> | <a href="strdup.3p.html#RATIONALE">RATIONALE</a> | <a href="strdup.3p.html#FUTURE_DIRECTIONS">FUTURE&nbsp;DIRECTIONS</a> | <a href="strdup.3p.html#SEE_ALSO">SEE&nbsp;ALSO</a> | <a href="strdup.3p.html#COPYRIGHT">COPYRIGHT</a>
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<pre>
<span class="headline">STRDUP(3P)                POSIX Programmer's Manual               STRDUP(3P)</span>
</pre>
<h2><a id="PROLOG" href="strdup.3p.html#PROLOG"></a>PROLOG  &nbsp; &nbsp; &nbsp; &nbsp; <a href="strdup.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="strdup.3p.html#NAME"></a>NAME  &nbsp; &nbsp; &nbsp; &nbsp; <a href="strdup.3p.html#top_of_page"><span class="top-link">top</span></a></h2><pre>
       strdup, strndup — duplicate a specific number of bytes from a string
</pre>
<h2><a id="SYNOPSIS" href="strdup.3p.html#SYNOPSIS"></a>SYNOPSIS  &nbsp; &nbsp; &nbsp; &nbsp; <a href="strdup.3p.html#top_of_page"><span class="top-link">top</span></a></h2><pre>
       #include &lt;string.h&gt;

       char *strdup(const char *<i>s</i>);
       char *strndup(const char *<i>s</i>, size_t <i>size</i>);
</pre>
<h2><a id="DESCRIPTION" href="strdup.3p.html#DESCRIPTION"></a>DESCRIPTION  &nbsp; &nbsp; &nbsp; &nbsp; <a href="strdup.3p.html#top_of_page"><span class="top-link">top</span></a></h2><pre>
       The <i>strdup</i>() function shall return a pointer to a new string, which
       is a duplicate of the string pointed to by <i>s</i>.  The returned pointer
       can be passed to <i>free</i>().  A null pointer is returned if the new
       string cannot be created.

       The <i>strndup</i>() function shall be equivalent to the <i>strdup</i>() function,
       duplicating the provided <i>s</i> in a new block of memory allocated as if
       by using <i>malloc</i>(), with the exception being that <i>strndup</i>() copies at
       most <i>size</i> plus one bytes into the newly allocated memory, terminating
       the new string with a NUL character. If the length of <i>s</i> is larger
       than <i>size</i>, only <i>size</i> bytes shall be duplicated. If <i>size</i> is larger
       than the length of <i>s</i>, all bytes in <i>s</i> shall be copied into the new
       memory buffer, including the terminating NUL character. The newly
       created string shall always be properly terminated.
</pre>
<h2><a id="RETURN_VALUE" href="strdup.3p.html#RETURN_VALUE"></a>RETURN VALUE  &nbsp; &nbsp; &nbsp; &nbsp; <a href="strdup.3p.html#top_of_page"><span class="top-link">top</span></a></h2><pre>
       The <i>strdup</i>() function shall return a pointer to a new string on
       success. Otherwise, it shall return a null pointer and set <i><a href="errno.3.html">errno</a></i> to
       indicate the error.

       Upon successful completion, the <i>strndup</i>() function shall return a
       pointer to the newly allocated memory containing the duplicated
       string. Otherwise, it shall return a null pointer and set <i><a href="errno.3.html">errno</a></i> to
       indicate the error.
</pre>
<h2><a id="ERRORS" href="strdup.3p.html#ERRORS"></a>ERRORS  &nbsp; &nbsp; &nbsp; &nbsp; <a href="strdup.3p.html#top_of_page"><span class="top-link">top</span></a></h2><pre>
       These functions shall fail if:

       <b>ENOMEM </b>Storage space available is insufficient.

       <i>The following sections are informative.</i>
</pre>
<h2><a id="EXAMPLES" href="strdup.3p.html#EXAMPLES"></a>EXAMPLES  &nbsp; &nbsp; &nbsp; &nbsp; <a href="strdup.3p.html#top_of_page"><span class="top-link">top</span></a></h2><pre>
       None.
</pre>
<h2><a id="APPLICATION_USAGE" href="strdup.3p.html#APPLICATION_USAGE"></a>APPLICATION USAGE  &nbsp; &nbsp; &nbsp; &nbsp; <a href="strdup.3p.html#top_of_page"><span class="top-link">top</span></a></h2><pre>
       For functions that allocate memory as if by <i>malloc</i>(), the application
       should release such memory when it is no longer required by a call to
       <i>free</i>().  For <i>strdup</i>() and <i>strndup</i>(), this is the return value.
</pre>
<h2><a id="RATIONALE" href="strdup.3p.html#RATIONALE"></a>RATIONALE  &nbsp; &nbsp; &nbsp; &nbsp; <a href="strdup.3p.html#top_of_page"><span class="top-link">top</span></a></h2><pre>
       None.
</pre>
<h2><a id="FUTURE_DIRECTIONS" href="strdup.3p.html#FUTURE_DIRECTIONS"></a>FUTURE DIRECTIONS  &nbsp; &nbsp; &nbsp; &nbsp; <a href="strdup.3p.html#top_of_page"><span class="top-link">top</span></a></h2><pre>
       None.
</pre>
<h2><a id="SEE_ALSO" href="strdup.3p.html#SEE_ALSO"></a>SEE ALSO  &nbsp; &nbsp; &nbsp; &nbsp; <a href="strdup.3p.html#top_of_page"><span class="top-link">top</span></a></h2><pre>
       <a href="free.3p.html">free(3p)</a>, <a href="wcsdup.3p.html">wcsdup(3p)</a>

       The Base Definitions volume of POSIX.1‐2008, <a href="../man0/string.h.0p.html">string.h(0p)</a>
</pre>
<h2><a id="COPYRIGHT" href="strdup.3p.html#COPYRIGHT"></a>COPYRIGHT  &nbsp; &nbsp; &nbsp; &nbsp; <a href="strdup.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                          STRDUP(3P)</span>
</pre>

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