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<h2>clock_sleep</h2>
<hr>
<p>
<strong>System Trap</strong> - Sleep until a given time.
<h3>SYNOPSIS</h3>
<pre>
<strong>kern_return_t   clock_sleep</strong>
                <strong>(mach_port_t</strong>                         <var>clock_name</var>,
                 <strong>sleep_type_t</strong>                        <var>sleep_type</var>,
                 <strong>tvalspec_t</strong>                          <var>sleep_time</var>,
                 <strong>clock_name</strong>                           <var>wake_time</var><strong>);</strong>
</pre>
<h3>PARAMETERS</h3>
<dl>
<p>
<dt><var>clock_name</var>
<dd>
[in clock-name send right] The name (or control) port for the clock.
<p>
<dt><var>sleep_type</var>
<dd>
[in scalar] How to interpret the sleep_time value:
     <dl>
<p>
<dt><strong>TIME_RELATIVE</strong>
<dd>
Interpret the sleep time as relative to the current time.
<p>
<dt><strong>TIME_ABSOLUTE</strong>
<dd>
Interpret the sleep time as an absolute time.
     </dl>
<p>
<dt><var>sleep_time</var>
<dd>
[in structure] The time when the sleep is to terminate.
<p>
<dt><var>wake_time</var>
<dd>
[out structure] The actual (absolute) time at which the sleep terminated.
</dl>

<h3>DESCRIPTION</h3>
<p>
The <strong>clock_sleep</strong> system trap delays the invoking
thread until a specified time.  This sleep may be aborted by
<strong>thread_abort</strong>.  Not all clocks provide this service
but the REALTIME clock must.
<p>
If the specified time is in the past, the call returns immediately
with the wake time being the current time.  If the clock's time is
changed (<strong>clock_set_time</strong>), the sleep will be
interrupted.  The thread will waken at the service time nearest the
specified sleep time as governed by the current clock alarm
resolution.
<h3>RETURN VALUES</h3>
<dl>
<p>
<dt> <strong>KERN_FAILURE</strong>
<dd>
The clock does not support a sleep service.
<p>
<dt> <strong>KERN_ABORTED</strong>
<dd>
The sleep was interrupted by thread_abort or terminated via use of 
clock_set_time.
</dl>
<h3>RELATED INFORMATION</h3>
<p>
Functions:
<a href="host_get_clock_service.html"><strong>host_get_clock_service</strong></a>,
<a href="clock_get_attributes.html"><strong>clock_get_attributes</strong></a>,
<a href="clock_get_time.html"><strong>clock_get_time</strong></a>,
<a href="clock_alarm.html"><strong>clock_alarm</strong></a>,
<a href="clock_set_time.html"><strong>clock_set_time</strong></a>,
<a href="thread_abort.html"><strong>thread_abort</strong></a>,
<p>
Data Structures:
tvalspec.