struct_hrtimer_clock_base(9) [centos man page]

STRUCT 
HRTIMER_CLOCK(9) 					   Driver Basics					   STRUCT HRTIMER_CLOCK(9)

NAME

       struct_hrtimer_clock_base - the timer base for a specific clock

SYNOPSIS

       struct hrtimer_clock_base {
	 struct hrtimer_cpu_base * cpu_base;
	 int index;
	 clockid_t clockid;
	 struct timerqueue_head active;
	 ktime_t resolution;
	 ktime_t (* get_time) (void);
	 ktime_t softirq_time;
	 ktime_t offset;
       };

MEMBERS

       cpu_base
	   per cpu clock base

       index
	   clock type index for per_cpu support when moving a timer to a base on another cpu.

       clockid
	   clock id for per_cpu support

       active
	   red black tree root node for the active timers

       resolution
	   the resolution of the clock, in nanoseconds

       get_time
	   function to retrieve the current time of the clock

       softirq_time
	   the time when running the hrtimer queue in the softirq

       offset
	   offset of this clock to the monotonic base

COPYRIGHT

Kernel Hackers Manual 3.10					     June 2014						   STRUCT HRTIMER_CLOCK(9)

clock_gettime(3)					     Library Functions Manual						  clock_gettime(3)

NAME

       clock_gettime, clock_settime - Obtains or sets the time for the specified clock (P1003.1b)

LIBRARY

       Realtime Library (librt.so, librt.a)

SYNOPSIS

       #include <time.h>

       int clock_gettime (
       clockid_t clock_id,
       struct timespec *tp);

       int clock_settime (
       clockid_t clock_id,
       const struct timespec *tp);

PARAMETERS

       clock_id    The	clock  type  used  to  obtain the time for the clock that is set. The CLOCK_REALTIME clock is supported and represents the
		   TIME-OF-DAY clock for the system.

       *tp	   A pointer to a timespec data structure.

DESCRIPTION

       The clock_gettime function returns the current time (in seconds and nanoseconds) for the specified clock.  The clock_settime function  sets
       the  specified  clock.  The  CLOCK_REALTIME clock measures the amount of time elapsed since 00:00:00:00 January 1, 1970 Greenwich Mean Time
       (GMT), otherwise known as the Epoch. Time values  that fall between two non-negative integer multiples of the resolution are truncated down
       to the smaller multiple of the resolution.

       You must have superuser privileges to use the clock_settime function.

RETURN VALUES

       On a successful call to the clock_gettime or clock_settime functions, a value of 0 (zero) is returned.

       On an unsuccessful call, a value of -1 is returned and errno is set to indicate that an error occurred.

ERRORS

       The clock_gettime and clock_settime functions fail under the following conditions:

       [EINVAL]       The clock_id argument does not specify a known clock.

		      The value pointed to by the tp argument to the clock_settime function is outside the range for the given clock_id.

		      The tp argument specified a nanosecond value less than zero or greater than or equal to 1000 million.

       [EPERM]	      The requesting process does not have the appropriate privilege to set the specified clock.

RELATED INFORMATION

       Functions: time(1), clock_getres(3), ctime(3), timer_gettime(3)

       Guide to Realtime Programming delim off

																  clock_gettime(3)