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href="/w/c/language" title="c/language">Language</a></td></tr> <tr class="t-nv"><td colspan="5"><a href="/w/c/header" title="c/header">Headers</a></td></tr> <tr class="t-nv"><td colspan="5"><a href="/w/c/types" title="c/types">Type support</a></td></tr> <tr class="t-nv"><td colspan="5"><a href="/w/c/program" title="c/program">Program utilities</a></td></tr> <tr class="t-nv"><td colspan="5"><a href="/w/c/variadic" title="c/variadic">Variadic function support</a></td></tr> <tr class="t-nv"><td colspan="5"><a href="/w/c/error" title="c/error">Error handling</a></td></tr> <tr class="t-nv"><td colspan="5"><a href="/w/c/memory" title="c/memory">Dynamic memory management</a></td></tr> <tr class="t-nv"><td colspan="5"><a href="/w/c/string" title="c/string">Strings library</a></td></tr> <tr class="t-nv"><td colspan="5"><a href="/w/c/algorithm" title="c/algorithm">Algorithms</a></td></tr> <tr class="t-nv"><td colspan="5"><a href="/w/c/numeric" title="c/numeric">Numerics</a></td></tr> <tr class="t-nv"><td colspan="5"><a href="/w/c/chrono" title="c/chrono">Date and time utilities</a></td></tr> <tr class="t-nv"><td colspan="5"><a href="/w/c/io" title="c/io">Input/output support</a></td></tr> <tr class="t-nv"><td colspan="5"><a href="/w/c/locale" title="c/locale">Localization support</a></td></tr> <tr class="t-nv"><td colspan="5"><a href="/w/c/thread" title="c/thread">Concurrency support</a> <span class="t-mark-rev t-since-c11">(C11)</span></td></tr> <tr class="t-nv"><td colspan="5"><a href="/w/c/experimental" title="c/experimental">Technical Specifications</a></td></tr> <tr class="t-nv"><td colspan="5"><a href="/w/c/symbol_index" title="c/symbol index">Symbol index</a></td></tr> </table></div><div><span class="editsection noprint plainlinks" title="Edit this template"><a rel="nofollow" class="external text" href="https://en.cppreference.com/mwiki/index.php?title=Template:c/navbar_content&action=edit">[edit]</a></span></div></div></div></div><div class="t-navbar-sep"> </div><div class="t-navbar-head"><a href="/w/c/chrono" title="c/chrono"> Date and time utilities</a><div class="t-navbar-menu"><div><div><table class="t-nv-begin" cellpadding="0" style=""> <tr class="t-nv-h1"><td colspan="5"> Functions</td></tr> <tr class="t-nv-h2"><td colspan="5"> Time manipulation</td></tr> <tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="/w/c/chrono/difftime" title="c/chrono/difftime"><span class="t-lines"><span>difftime</span></span></a></div></div></td></tr> <tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="/w/c/chrono/time" title="c/chrono/time"><span class="t-lines"><span>time</span></span></a></div></div></td></tr> <tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="/w/c/chrono/clock" title="c/chrono/clock"><span class="t-lines"><span>clock</span></span></a></div></div></td></tr> <tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="/w/c/chrono/timespec_get" title="c/chrono/timespec get"><span class="t-lines"><span>timespec_get</span></span></a></div><div><span class="t-lines"><span><span class="t-mark-rev t-since-c11">(C11)</span></span></span></div></div></td></tr> <tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="/w/c/chrono/timespec_getres" title="c/chrono/timespec getres"><span class="t-lines"><span>timespec_getres</span></span></a></div><div><span class="t-lines"><span><span class="t-mark-rev t-since-c23">(C23)</span></span></span></div></div></td></tr> <tr class="t-nv-h2"><td colspan="5"> Format conversions</td></tr> <tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><strong class="selflink"><span class="t-lines"><span>asctime</span><span>asctime_s</span></span></strong></div><div><span class="t-lines"><span><span class="t-mark-rev t-deprecated-c23">(deprecated in C23)</span></span><span><span class="t-mark-rev t-since-c11">(C11)</span></span></span></div></div></td></tr> <tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="/w/c/chrono/ctime" title="c/chrono/ctime"><span class="t-lines"><span>ctime</span><span>ctime_s</span></span></a></div><div><span class="t-lines"><span><span class="t-mark-rev t-deprecated-c23">(deprecated in C23)</span></span><span><span class="t-mark-rev t-since-c11">(C11)</span></span></span></div></div></td></tr> <tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="/w/c/chrono/strftime" title="c/chrono/strftime"><span class="t-lines"><span>strftime</span></span></a></div></div></td></tr> <tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="/w/c/chrono/wcsftime" title="c/chrono/wcsftime"><span class="t-lines"><span>wcsftime</span></span></a></div><div><span class="t-lines"><span><span class="t-mark-rev t-since-c95">(C95)</span></span></span></div></div></td></tr> <tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="/w/c/chrono/gmtime" title="c/chrono/gmtime"><span class="t-lines"><span>gmtime</span><span>gmtime_r</span><span>gmtime_s</span></span></a></div><div><span class="t-lines"><span></span><span><span class="t-mark-rev t-since-c23">(C23)</span></span><span><span class="t-mark-rev t-since-c11">(C11)</span></span></span></div></div></td></tr> <tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="/w/c/chrono/localtime" title="c/chrono/localtime"><span class="t-lines"><span>localtime</span><span>localtime_r</span><span>localtime_s</span></span></a></div><div><span class="t-lines"><span></span><span><span class="t-mark-rev t-since-c23">(C23)</span></span><span><span class="t-mark-rev t-since-c11">(C11)</span></span></span></div></div></td></tr> <tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="/w/c/chrono/mktime" title="c/chrono/mktime"><span class="t-lines"><span>mktime</span></span></a></div></div></td></tr> <tr class="t-nv-h1"><td colspan="5"> Constants</td></tr> <tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="/w/c/chrono/CLOCKS_PER_SEC" title="c/chrono/CLOCKS PER SEC"><span class="t-lines"><span>CLOCKS_PER_SEC</span></span></a></div></div></td></tr> <tr class="t-nv-h1"><td colspan="5"> Types</td></tr> <tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="/w/c/chrono/tm" title="c/chrono/tm"><span class="t-lines"><span>tm</span></span></a></div></div></td></tr> <tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="/w/c/chrono/time_t" title="c/chrono/time t"><span class="t-lines"><span>time_t</span></span></a></div></div></td></tr> <tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="/w/c/chrono/clock_t" title="c/chrono/clock t"><span class="t-lines"><span>clock_t</span></span></a></div></div></td></tr> <tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="/w/c/chrono/timespec" title="c/chrono/timespec"><span class="t-lines"><span>timespec</span></span></a></div><div><span class="t-lines"><span><span class="t-mark-rev t-since-c11">(C11)</span></span></span></div></div></td></tr> </table></div><div><span class="editsection noprint plainlinks" title="Edit this template"><a rel="nofollow" class="external text" href="https://en.cppreference.com/mwiki/index.php?title=Template:c/chrono/navbar_content&action=edit">[edit]</a></span></div></div></div></div><div class="t-navbar-sep"> </div></div> <table class="t-dcl-begin"><tbody> <tr class="t-dsc-header"> <td> <div>Defined in header <code><time.h></code> </div></td> <td></td> <td></td> </tr> </tbody> <tbody class="t-dcl-rev t-dcl-rev-num"><tr class="t-dcl-rev-aux"> <td></td> <td rowspan="142">(1)</td> <td></td> </tr> <tr class="t-dcl t-until-c23"> <td><div><span class="mw-geshi c source-c"><span class="kw4">char</span><span class="sy2">*</span>                asctime<span class="br0">(</span> <span class="kw4">const</span> <span class="kw1">struct</span> <a href="http://en.cppreference.com/w/c/chrono/tm"><span class="kw522">tm</span></a><span class="sy2">*</span> time_ptr <span class="br0">)</span><span class="sy4">;</span></span></div></td> <td class="t-dcl-nopad"> </td> <td><span class="t-mark-rev t-until-c23">(until C23)</span></td> </tr> <tr class="t-dcl t-since-c23"> <td> <div><span class="mw-geshi c source-c"><span class="br0">[</span><span class="br0">[</span>deprecated<span class="br0">]</span><span class="br0">]</span> <span class="kw4">char</span><span class="sy2">*</span> asctime<span class="br0">(</span> <span class="kw4">const</span> <span class="kw1">struct</span> <a href="http://en.cppreference.com/w/c/chrono/tm"><span class="kw522">tm</span></a><span class="sy2">*</span> time_ptr <span class="br0">)</span><span class="sy4">;</span></span></div></td> <td class="t-dcl-nopad"> </td> <td> <span class="t-mark-rev t-since-c23">(since C23)</span> </td> </tr> </tbody><tbody> <tr class="t-dcl t-since-c11"> <td> <div><span class="mw-geshi c source-c">errno_t asctime_s<span class="br0">(</span> <span class="kw4">char</span><span class="sy2">*</span> buf, rsize_t bufsz, <span class="kw4">const</span> <span class="kw1">struct</span> <a href="http://en.cppreference.com/w/c/chrono/tm"><span class="kw522">tm</span></a><span class="sy2">*</span> time_ptr <span class="br0">)</span><span class="sy4">;</span></span></div></td> <td> (2) </td> <td> <span class="t-mark-rev t-since-c11">(since C11)</span> </td> </tr> <tr class="t-dcl-sep"><td></td><td></td><td></td></tr> </tbody></table> <div class="t-li1"><span class="t-li">1)</span> Converts given calendar time <span class="t-lc"><a href="/w/c/chrono/tm" title="c/chrono/tm">tm</a></span> to a textual representation of the following fixed 25-character form: <span class="t-c"><span class="mw-geshi c source-c">Www Mmm dd hh<span class="sy4">:</span>mm<span class="sy4">:</span>ss yyyy\n</span></span> <ul><li><code>Www</code> - three-letter English abbreviated day of the week from <span class="t-c"><span class="mw-geshi c source-c">time_ptr<span class="sy2">-</span><span class="sy1">></span>tm_wday</span></span>, one of <code>Mon</code>, <code>Tue</code>, <code>Wed</code>, <code>Thu</code>, <code>Fri</code>, <code>Sat</code>, <code>Sun</code>. </li><li><code>Mmm</code> - three-letter English abbreviated month name from <span class="t-c"><span class="mw-geshi c source-c">time_ptr<span class="sy2">-</span><span class="sy1">></span>tm_mon</span></span>, one of <code>Jan</code>, <code>Feb</code>, <code>Mar</code>, <code>Apr</code>, <code>May</code>, <code>Jun</code>, <code>Jul</code>, <code>Aug</code>, <code>Sep</code>, <code>Oct</code>, <code>Nov</code>, <code>Dec</code>. </li><li><code>dd</code> - 2-digit day of the month from <span class="t-c"><span class="mw-geshi c source-c">timeptr<span class="sy2">-</span><span class="sy1">></span>tm_mday</span></span> as if printed by <span class="t-lc"><a href="/w/c/io/fprintf" title="c/io/fprintf">sprintf</a></span> using <span class="t-c"><span class="mw-geshi c source-c"><span class="sy2">%</span>2d</span></span>. </li><li><code>hh</code> - 2-digit hour from <span class="t-c"><span class="mw-geshi c source-c">timeptr<span class="sy2">-</span><span class="sy1">></span>tm_hour</span></span> as if printed by <span class="t-lc"><a href="/w/c/io/fprintf" title="c/io/fprintf">sprintf</a></span> using <span class="t-c"><span class="mw-geshi c source-c"><span class="sy2">%</span>.2d</span></span>. </li><li><code>mm</code> - 2-digit minute from <span class="t-c"><span class="mw-geshi c source-c">timeptr<span class="sy2">-</span><span class="sy1">></span>tm_min</span></span> as if printed by <span class="t-lc"><a href="/w/c/io/fprintf" title="c/io/fprintf">sprintf</a></span> using <span class="t-c"><span class="mw-geshi c source-c"><span class="sy2">%</span>.2d</span></span>. </li><li><code>ss</code> - 2-digit second from <span class="t-c"><span class="mw-geshi c source-c">timeptr<span class="sy2">-</span><span class="sy1">></span>tm_sec</span></span> as if printed by <span class="t-lc"><a href="/w/c/io/fprintf" title="c/io/fprintf">sprintf</a></span> using <span class="t-c"><span class="mw-geshi c source-c"><span class="sy2">%</span>.2d</span></span>. </li><li><code>yyyy</code> - 4-digit year from <span class="t-c"><span class="mw-geshi c source-c">timeptr<span class="sy2">-</span><span class="sy1">></span>tm_year <span class="sy2">+</span> <span class="nu0">1900</span></span></span> as if printed by <span class="t-lc"><a href="/w/c/io/fprintf" title="c/io/fprintf">sprintf</a></span> using <span class="t-c"><span class="mw-geshi c source-c"><span class="sy2">%</span>4d</span></span>.</div> </li></ul> <div class="t-li1"><span class="t-li"></span> The behavior is undefined if any member of <span class="t-c"><span class="mw-geshi c source-c"><span class="sy2">*</span>time_ptr</span></span> is outside its normal range.</div> <div class="t-li1"><span class="t-li"></span> The behavior is undefined if the calendar year indicated by <span class="t-c"><span class="mw-geshi c source-c">time_ptr<span class="sy2">-</span><span class="sy1">></span>tm_year</span></span> has more than 4 digits or is less than the year 1000.</div> <div class="t-li1"><span class="t-li"></span> The function does not support localization, and the newline character cannot be removed.</div> <div class="t-li1"><span class="t-li"></span> The function modifies static storage and is not thread-safe.</div> <table class="t-rev-begin"> <tr class="t-rev t-since-c23"><td> <div class="t-li1"><span class="t-li"></span> This function is deprecated and should not be used in new code.</div> </td> <td><span class="t-mark-rev t-since-c23">(since C23)</span></td></tr> </table> <div class="t-li1"><span class="t-li">2)</span> Same as <span class="t-v">(1)</span>, except that the message is written into user-provided storage <span class="t-c"><span class="mw-geshi c source-c">buf</span></span>, which is guaranteed to be null-terminated, and the following errors are detected at runtime and call the currently installed <a href="/w/c/error/set_constraint_handler_s" title="c/error/set constraint handler s">constraint handler</a> function: <dl><dd><ul><li> <span class="t-c"><span class="mw-geshi c source-c">buf</span></span> or <span class="t-c"><span class="mw-geshi c source-c">time_ptr</span></span> is a null pointer </li><li> <span class="t-c"><span class="mw-geshi c source-c">bufsz</span></span> is less than 26 or greater than <span class="t-lc">RSIZE_MAX</span> </li><li> not all members of <span class="t-c"><span class="mw-geshi c source-c"><span class="sy2">*</span>time_ptr</span></span> are within their normal ranges </li><li> the year indicated by <span class="t-c"><span class="mw-geshi c source-c">time_ptr<span class="sy2">-</span><span class="sy1">></span>tm_year</span></span> is less than 0 or greater than 9999. </li></ul> </dd><dd>As with all bounds-checked functions, <code>asctime_s</code> is only guaranteed to be available if <span class="t-c"><span class="mw-geshi c source-c">__STDC_LIB_EXT1__</span></span> is defined by the implementation and if the user defines <span class="t-c"><span class="mw-geshi c source-c">__STDC_WANT_LIB_EXT1__</span></span> to the integer constant <span class="t-c"><span class="mw-geshi c source-c"><span class="nu0">1</span></span></span> before including <a href="/w/c/chrono" title="c/chrono"><tt><time.h></tt></a>.</div> </dd></dl> <table id="toc" class="toc"><tr><td><div id="toctitle"><h2>Contents</h2></div> <ul> <li class="toclevel-1 tocsection-1"><a href="#Parameters"><span class="tocnumber">1</span> <span class="toctext">Parameters</span></a></li> <li class="toclevel-1 tocsection-2"><a href="#Return_value"><span class="tocnumber">2</span> <span class="toctext">Return value</span></a></li> <li class="toclevel-1 tocsection-3"><a href="#Notes"><span class="tocnumber">3</span> <span class="toctext">Notes</span></a></li> <li class="toclevel-1 tocsection-4"><a href="#Example"><span class="tocnumber">4</span> <span class="toctext">Example</span></a></li> <li class="toclevel-1 tocsection-5"><a href="#References"><span class="tocnumber">5</span> <span class="toctext">References</span></a></li> <li class="toclevel-1 tocsection-6"><a href="#See_also"><span class="tocnumber">6</span> <span class="toctext">See also</span></a></li> </ul> </td></tr></table> <h3><span class="editsection">[<a href="/mwiki/index.php?title=c/chrono/asctime&action=edit&section=1" title="Edit section: Parameters">edit</a>]</span> <span class="mw-headline" id="Parameters">Parameters</span></h3> <table class="t-par-begin"> <tr class="t-par"> <td> time_ptr </td> <td> - </td> <td> pointer to a <span class="t-lc"><a href="/w/c/chrono/tm" title="c/chrono/tm">tm</a></span> object specifying the time to print </td></tr> <tr class="t-par"> <td> buf </td> <td> - </td> <td> pointer to a user-supplied buffer at least 26 bytes in length </td></tr> <tr class="t-par"> <td> bufsz </td> <td> - </td> <td> size of the user-supplied buffer </td></tr></table> <h3><span class="editsection">[<a href="/mwiki/index.php?title=c/chrono/asctime&action=edit&section=2" title="Edit section: Return value">edit</a>]</span> <span class="mw-headline" id="Return_value">Return value</span></h3> <div class="t-li1"><span class="t-li">1)</span> pointer to a static null-terminated character string holding the textual representation of date and time as described above. The string may be shared between <code>asctime</code> and <span class="t-lc"><a href="/w/c/chrono/ctime" title="c/chrono/ctime">ctime</a></span>, and may be overwritten on each invocation of any of those functions.</div> <div class="t-li1"><span class="t-li">2)</span> zero on success, non-zero on failure, in which case <span class="t-c"><span class="mw-geshi c source-c">buf<span class="br0">[</span><span class="nu0">0</span><span class="br0">]</span></span></span> is set to zero (unless <span class="t-c"><span class="mw-geshi c source-c">buf</span></span> is a null pointer or <span class="t-c"><span class="mw-geshi c source-c">bufsz</span></span> is zero or greater than <span class="t-lc">RSIZE_MAX</span>).</div> <h3><span class="editsection">[<a href="/mwiki/index.php?title=c/chrono/asctime&action=edit&section=3" title="Edit section: Notes">edit</a>]</span> <span class="mw-headline" id="Notes">Notes</span></h3> <p><code>asctime</code> returns a pointer to static data and is not thread-safe. POSIX marks this function obsolete and recommends <span class="t-lc"><a href="/w/c/chrono/strftime" title="c/chrono/strftime">strftime</a></span> instead. The C standard also recommends <span class="t-lc"><a href="/w/c/chrono/strftime" title="c/chrono/strftime">strftime</a></span> instead of <code>asctime</code> and <code>asctime_s</code> because <code>strftime</code> is more flexible and locale-sensitive. </p><p>POSIX limits undefined behaviors only to when the output string would be longer than 25 characters, when <span class="t-c"><span class="mw-geshi c source-c">timeptr<span class="sy2">-</span><span class="sy1">></span>tm_wday</span></span> or <span class="t-c"><span class="mw-geshi c source-c">timeptr<span class="sy2">-</span><span class="sy1">></span>tm_mon</span></span> are not within the expected ranges, or when <span class="t-c"><span class="mw-geshi c source-c">timeptr<span class="sy2">-</span><span class="sy1">></span>tm_year</span></span> exceeds <span class="t-c"><span class="mw-geshi c source-c"><a href="http://en.cppreference.com/w/c/types/limits"><span class="kw364">INT_MAX</span></a> <span class="sy2">-</span> <span class="nu0">1990</span></span></span>. </p><p>Some implementations handle <span class="t-c"><span class="mw-geshi c source-c">timeptr<span class="sy2">-</span><span class="sy1">></span>tm_mday <span class="sy1">==</span> <span class="nu0">0</span></span></span> as meaning the last day of the preceding month. </p> <h3><span class="editsection">[<a href="/mwiki/index.php?title=c/chrono/asctime&action=edit&section=4" title="Edit section: Example">edit</a>]</span> <span class="mw-headline" id="Example">Example</span></h3> <div class="t-example"><div class="t-example-live-link"><div class="coliru-btn coliru-btn-run-init">Run this code</div></div> <div dir="ltr" class="mw-geshi" style="text-align: left;"><div class="c source-c"><pre class="de1"><span class="co2">#define __STDC_WANT_LIB_EXT1__ 1</span> <span class="co2">#include <stdio.h></span> <span class="co2">#include <time.h></span>   <span class="kw4">int</span> main<span class="br0">(</span><span class="kw4">void</span><span class="br0">)</span> <span class="br0">{</span> <span class="kw1">struct</span> <a href="http://en.cppreference.com/w/c/chrono/tm"><span class="kw522">tm</span></a> <a href="http://en.cppreference.com/w/c/chrono/tm"><span class="kw522">tm</span></a> <span class="sy1">=</span> <span class="sy2">*</span><a href="http://en.cppreference.com/w/c/chrono/localtime"><span class="kw519">localtime</span></a><span class="br0">(</span><span class="sy3">&</span><span class="br0">(</span><a href="http://en.cppreference.com/w/c/chrono/time_t"><span class="kw523">time_t</span></a><span class="br0">)</span><span class="br0">{</span><a href="http://en.cppreference.com/w/c/chrono/time"><span class="kw513">time</span></a><span class="br0">(</span><a href="http://en.cppreference.com/w/c/types/NULL"><span class="kw103">NULL</span></a><span class="br0">)</span><span class="br0">}</span><span class="br0">)</span><span class="sy4">;</span> <a href="http://en.cppreference.com/w/c/io/fprintf"><span class="kw850">printf</span></a><span class="br0">(</span><span class="st0">"%s"</span>, asctime<span class="br0">(</span><span class="sy3">&</span><a href="http://en.cppreference.com/w/c/chrono/tm"><span class="kw522">tm</span></a><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span> <span class="co1">// note implicit trailing '\n'</span>   <span class="co2">#ifdef __STDC_LIB_EXT1__</span> <span class="kw4">char</span> str<span class="br0">[</span><span class="nu0">26</span><span class="br0">]</span><span class="sy4">;</span> asctime_s<span class="br0">(</span>str, <span class="kw4">sizeof</span> str, <span class="sy3">&</span><a href="http://en.cppreference.com/w/c/chrono/tm"><span class="kw522">tm</span></a><span class="br0">)</span><span class="sy4">;</span> <a href="http://en.cppreference.com/w/c/io/fprintf"><span class="kw850">printf</span></a><span class="br0">(</span><span class="st0">"%s"</span>, str<span class="br0">)</span><span class="sy4">;</span> <span class="co2">#endif</span> <span class="br0">}</span></pre></div></div> <p>Possible output: </p> <div dir="ltr" class="mw-geshi" style="text-align: left;"><div class="text source-text"><pre class="de1">Tue May 26 21:51:50 2015 Tue May 26 21:51:50 2015</pre></div></div> </div> <h3><span class="editsection">[<a href="/mwiki/index.php?title=c/chrono/asctime&action=edit&section=5" title="Edit section: References">edit</a>]</span> <span class="mw-headline" id="References">References</span></h3> <div class="t-ref-std-17"> <ul><li> C17 standard (ISO/IEC 9899:2018): </li></ul> <dl><dd><ul><li> 7.27.2.1 The asctime function (p: 287) </li></ul> </dd></dl> <dl><dd><ul><li> K.3.8.2.1 The asctime_s function (p: 453-454) </li></ul> </dd></dl> </div> <div class="t-ref-std-11"> <ul><li> C11 standard (ISO/IEC 9899:2011): </li></ul> <dl><dd><ul><li> 7.27.2.1 The asctime function (p: 392-393) </li></ul> </dd></dl> <dl><dd><ul><li> K.3.8.2.1 The asctime_s function (p: 624-625) </li></ul> </dd></dl> </div> <div class="t-ref-std-c99"> <ul><li> C99 standard (ISO/IEC 9899:1999): </li></ul> <dl><dd><ul><li> 7.23.3.1 The asctime function (p: 341-342) </li></ul> </dd></dl> </div> <div class="t-ref-std-c89"> <ul><li> C89/C90 standard (ISO/IEC 9899:1990): </li></ul> <dl><dd><ul><li> 4.12.3.1 The asctime function </li></ul> </dd></dl> </div> <h3><span class="editsection">[<a href="/mwiki/index.php?title=c/chrono/asctime&action=edit&section=6" title="Edit section: See also">edit</a>]</span> <span class="mw-headline" id="See_also">See also</span></h3> <table class="t-dsc-begin"> <tr class="t-dsc"> <td> <div class="t-dsc-member-div"><div><a href="/w/c/chrono/ctime" title="c/chrono/ctime"> <span class="t-lines"><span>ctime</span><span>ctime_s</span></span></a></div><div><span class="t-lines"><span><span class="t-mark-rev t-deprecated-c23">(deprecated in C23)</span></span><span><span class="t-mark-rev t-since-c11">(C11)</span></span></span></div></div> </td> <td> converts a <span class="t-lc"><a href="/w/c/chrono/time_t" title="c/chrono/time t">time_t</a></span> object to a textual representation <br /> <span class="t-mark">(function)</span> <span class="editsection noprint plainlinks" title="Edit this template"><a rel="nofollow" class="external text" href="https://en.cppreference.com/mwiki/index.php?title=Template:c/chrono/dsc_ctime&action=edit">[edit]</a></span> </td></tr> <tr class="t-dsc"> <td> <div class="t-dsc-member-div"><div><a href="/w/c/chrono/strftime" title="c/chrono/strftime"> <span class="t-lines"><span>strftime</span></span></a></div></div> </td> <td> converts a <span class="t-lc"><a href="/w/c/chrono/tm" title="c/chrono/tm">tm</a></span> object to custom textual representation <br /> <span class="t-mark">(function)</span> <span class="editsection noprint plainlinks" title="Edit this template"><a rel="nofollow" class="external text" href="https://en.cppreference.com/mwiki/index.php?title=Template:c/chrono/dsc_strftime&action=edit">[edit]</a></span> </td></tr> <tr class="t-dsc"> <td colspan="2"> <div class="t-dsc-see"><span><a href="/w/cpp/chrono/c/asctime" title="cpp/chrono/c/asctime">C++ documentation</a></span> for <span class="t-dsc-see-tt"><span>asctime</span></span></div> </td></tr> </table>   </div>   <div class="printfooter"> Retrieved from "<a href="https://en.cppreference.com/mwiki/index.php?title=c/chrono/asctime&oldid=172468">https://en.cppreference.com/mwiki/index.php?title=c/chrono/asctime&oldid=172468</a>" </div>   <div id='catlinks' class='catlinks catlinks-allhidden'></div>  <div class="visualClear"></div>   </div>  </div> </div>   <div id="cpp-footer-base" class="noprint"> <div id="footer"> <div id="cpp-navigation"> <h5>Navigation</h5> <ul> <li id="n-Support-us"><a href="http://www.cppreference.com/support" rel="nofollow">Support us</a></li><li id="n-recentchanges"><a 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