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Host Get Clock Control

osfmk/man/host_get_clock_control.html

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host_get_clock_control


Function - Return a send right to a kernel clock's control port.

SYNOPSIS

**kern\_return\_t host\_get\_clock\_control**** (host\_priv\_t **host\_priv,** clock\_id\_t **id,** clock\_ctrl\_t **clock\_control** );**

PARAMETERS

host_priv[in host-control send right] The control port for the host owning the clock.

id[in scalar] The identification of the desired kernel clock. These values are defined in *L*O. Although an implementation may define additional values, the following values are always defined (although only the REALTIME clock is required to be implemented):

REALTIME_CLOCK A moderate resolution clock service that (typically) tracks time since the system last boot.

BATTERY_CLOCK A (typically) low resolution clock (to the second) that survives power failures or service outages.

HIGHRES_CLOCK A high resolution clock.

clock_control[out clock-control send right] Control port for the clock.

DESCRIPTION

The host_get_clock_control function returns a send right to the control port for a kernel clock object. This right is used to set the clock's resolution and time.

RETURN VALUES

Only generic errors apply.

Functions: clock_set_time, clock_set_attributes, host_get_clock_service.