xref: /xnu-10002.1.13/osfmk/man/host_get_clock_control.html (revision 1031c584a5e37aff177559b9f69dbd3c8c3fd30a)
1*1031c584SApple OSS Distributions<h2>host_get_clock_control</h2>
2*1031c584SApple OSS Distributions<hr>
3*1031c584SApple OSS Distributions<p>
4*1031c584SApple OSS Distributions<strong>Function</strong> - Return a send right to a kernel clock's control port.
5*1031c584SApple OSS Distributions<h3>SYNOPSIS</h3>
6*1031c584SApple OSS Distributions<pre>
7*1031c584SApple OSS Distributions<strong>kern_return_t   host_get_clock_control</strong>
8*1031c584SApple OSS Distributions                <strong>(host_priv_t</strong>                          <var>host_priv</var>,
9*1031c584SApple OSS Distributions                 <strong>clock_id_t</strong>                                  <var>id</var>,
10*1031c584SApple OSS Distributions                 <strong>clock_ctrl_t</strong>                     <var>clock_control</var><strong>);</strong>
11*1031c584SApple OSS Distributions</pre>
12*1031c584SApple OSS Distributions<h3>PARAMETERS</h3>
13*1031c584SApple OSS Distributions<dl>
14*1031c584SApple OSS Distributions<p>
15*1031c584SApple OSS Distributions<dt> <var>host_priv</var>
16*1031c584SApple OSS Distributions<dd>
17*1031c584SApple OSS Distributions[in host-control send right]
18*1031c584SApple OSS DistributionsThe control port for the host owning the
19*1031c584SApple OSS Distributionsclock.
20*1031c584SApple OSS Distributions<p>
21*1031c584SApple OSS Distributions<dt> <var>id</var>
22*1031c584SApple OSS Distributions<dd>
23*1031c584SApple OSS Distributions[in scalar]
24*1031c584SApple OSS DistributionsThe identification of the desired kernel clock.  These values
25*1031c584SApple OSS Distributionsare defined in \*L<mach/clock_types.h>\*O.  Although an implementation
26*1031c584SApple OSS Distributionsmay define additional values, the following values are always defined
27*1031c584SApple OSS Distributions(although only the REALTIME clock is required to be implemented):
28*1031c584SApple OSS Distributions<dl>
29*1031c584SApple OSS Distributions<p>
30*1031c584SApple OSS Distributions<dt> <strong>REALTIME_CLOCK</strong>
31*1031c584SApple OSS Distributions<dd>
32*1031c584SApple OSS DistributionsA moderate resolution clock service that (typically) tracks
33*1031c584SApple OSS Distributionstime since the system last boot.
34*1031c584SApple OSS Distributions<p>
35*1031c584SApple OSS Distributions<dt> <strong>BATTERY_CLOCK</strong>
36*1031c584SApple OSS Distributions<dd>
37*1031c584SApple OSS DistributionsA (typically) low resolution clock (to the second) that
38*1031c584SApple OSS Distributionssurvives power failures or service outages.
39*1031c584SApple OSS Distributions<p>
40*1031c584SApple OSS Distributions<dt> <strong>HIGHRES_CLOCK</strong>
41*1031c584SApple OSS Distributions<dd>
42*1031c584SApple OSS DistributionsA high resolution clock.
43*1031c584SApple OSS Distributions</dl>
44*1031c584SApple OSS Distributions<p>
45*1031c584SApple OSS Distributions<dt> <var>clock_control</var>
46*1031c584SApple OSS Distributions<dd>
47*1031c584SApple OSS Distributions[out clock-control send right]
48*1031c584SApple OSS DistributionsControl port for the clock.
49*1031c584SApple OSS Distributions</dl>
50*1031c584SApple OSS Distributions<h3>DESCRIPTION</h3>
51*1031c584SApple OSS Distributions<p>
52*1031c584SApple OSS DistributionsThe <strong>host_get_clock_control</strong> function returns a send
53*1031c584SApple OSS Distributionsright to the control port for
54*1031c584SApple OSS Distributionsa kernel clock object.  This right is used to set the clock's
55*1031c584SApple OSS Distributionsresolution and time.
56*1031c584SApple OSS Distributions<h3>RETURN VALUES</h3>
57*1031c584SApple OSS Distributions<p>
58*1031c584SApple OSS DistributionsOnly generic errors apply.
59*1031c584SApple OSS Distributions<h3>RELATED INFORMATION</h3>
60*1031c584SApple OSS Distributions<p>
61*1031c584SApple OSS DistributionsFunctions:
62*1031c584SApple OSS Distributions<a href="clock_set_time.html"><strong>clock_set_time</strong></a>,
63*1031c584SApple OSS Distributions<a href="clock_set_attributes.html"><strong>clock_set_attributes</strong></a>,
64*1031c584SApple OSS Distributions<a href="host_get_clock_service.html"><strong>host_get_clock_service</strong></a>.
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