hrtimer_get_res(9) [centos man page]

HRTIMER_GET_RES(9)						   Driver Basics						HRTIMER_GET_RES(9)

NAME

       hrtimer_get_res - get the timer resolution for a clock

SYNOPSIS

       int hrtimer_get_res(const clockid_t which_clock, struct timespec * tp);

ARGUMENTS

       which_clock
	   which clock to query

       tp
	   pointer to timespec variable to store the resolution

DESCRIPTION

       Store the resolution of the clock selected by which_clock in the variable pointed to by tp.

COPYRIGHT

Kernel Hackers Manual 3.10					     June 2014							HRTIMER_GET_RES(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)