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<h4 class="subsection">21.3.2 Processor Time Inquiry</h4>

<p>The <code>times</code> function returns information about a process'
consumption of processor time in a <code>struct&nbsp;tms</code><!-- /@w --> object, in
addition to the process' CPU time.  See <a href="Time-Basics.html#Time-Basics">Time Basics</a>.  You should
include the header file <samp><span class="file">sys/times.h</span></samp> to use this facility. 
<a name="index-processor-time-2611"></a><a name="index-CPU-time-2612"></a><a name="index-sys_002ftimes_002eh-2613"></a>
<!-- sys/times.h -->
<!-- POSIX.1 -->

<div class="defun">
&mdash; Data Type: <b>struct tms</b><var><a name="index-struct-tms-2614"></a></var><br>
<blockquote><p>The <code>tms</code> structure is used to return information about process
times.  It contains at least the following members:

          <dl>
<dt><code>clock_t tms_utime</code><dd>This is the total processor time the calling process has used in
executing the instructions of its program.

          <br><dt><code>clock_t tms_stime</code><dd>This is the processor time the system has used on behalf of the calling
process.

          <br><dt><code>clock_t tms_cutime</code><dd>This is the sum of the <code>tms_utime</code> values and the <code>tms_cutime</code>
values of all terminated child processes of the calling process, whose
status has been reported to the parent process by <code>wait</code> or
<code>waitpid</code>; see <a href="Process-Completion.html#Process-Completion">Process Completion</a>.  In other words, it
represents the total processor time used in executing the instructions
of all the terminated child processes of the calling process, excluding
child processes which have not yet been reported by <code>wait</code> or
<code>waitpid</code>. 
<a name="index-child-process-2615"></a>
<br><dt><code>clock_t tms_cstime</code><dd>This is similar to <code>tms_cutime</code>, but represents the total processor
time system has used on behalf of all the terminated child processes
of the calling process. 
</dl>

        <p>All of the times are given in numbers of clock ticks.  Unlike CPU time,
these are the actual amounts of time; not relative to any event. 
See <a href="Creating-a-Process.html#Creating-a-Process">Creating a Process</a>. 
</p></blockquote></div>

<!-- sys/times.h -->
<!-- POSIX.1 -->
<div class="defun">
&mdash; Function: clock_t <b>times</b> (<var>struct tms *buffer</var>)<var><a name="index-times-2616"></a></var><br>
<blockquote><p>The <code>times</code> function stores the processor time information for
the calling process in <var>buffer</var>.

        <p>The return value is the calling process' CPU time (the same value you
get from <code>clock()</code>.  <code>times</code> returns <code>(clock_t)(-1)</code> to
indicate failure. 
</p></blockquote></div>

   <p><strong>Portability Note:</strong> The <code>clock</code> function described in
<a href="CPU-Time.html#CPU-Time">CPU Time</a> is specified by the ISO&nbsp;C<!-- /@w --> standard.  The
<code>times</code> function is a feature of POSIX.1.  In the GNU system, the
CPU time is defined to be equivalent to the sum of the <code>tms_utime</code>
and <code>tms_stime</code> fields returned by <code>times</code>.

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