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<h3 class="section">8.167 <code>MCLOCK8</code> — Time function (64-bit)</h3>
<p><a name="index-MCLOCK8-841"></a><a name="index-time_002c-clock-ticks-842"></a><a name="index-clock-ticks-843"></a>
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<dt><em>Description</em>:<dd>Returns the number of clock ticks since the start of the process, based
on the UNIX function <code>clock(3)</code>.
<p><em>Warning:</em> this intrinsic does not increase the range of the timing
values over that returned by <code>clock(3)</code>. On a system with a 32-bit
<code>clock(3)</code>, <code>MCLOCK8</code> will return a 32-bit value, even though
it is converted to a 64-bit <code>INTEGER(8)</code> value. That means
overflows of the 32-bit value can still occur. Therefore, the values
returned by this intrinsic might be or become negative or numerically
less than previous values during a single run of the compiled program.
<br><dt><em>Standard</em>:<dd>GNU extension
<br><dt><em>Class</em>:<dd>Function
<br><dt><em>Syntax</em>:<dd><code>RESULT = MCLOCK8()</code>
<br><dt><em>Return value</em>:<dd>The return value is a scalar of type <code>INTEGER(8)</code>, equal to the
number of clock ticks since the start of the process, or <code>-1</code> if
the system does not support <code>clock(3)</code>.
<br><dt><em>See also</em>:<dd><a href="CTIME.html#CTIME">CTIME</a>, <a href="GMTIME.html#GMTIME">GMTIME</a>, <a href="LTIME.html#LTIME">LTIME</a>, <a href="MCLOCK.html#MCLOCK">MCLOCK</a>, <a href="TIME8.html#TIME8">TIME8</a>
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