setclock(3) [osf1 man page]

setclock(3)						     Library Functions Manual						       setclock(3)

NAME

       setclock - Sets value of system-wide clock

LIBRARY

       Standard C Library (libc.a)

SYNOPSIS

       #include <sys/timers.h>
       int setclock(	  int clktyp,	   struct timespec *val) ;

PARAMETERS

       Specifies  a  system-wide  clock whose symbolic name must be TIMEOFDAY.	Points to the location where the value of the time to set into the
       clock specified by the clktyp parameter is stored.

DESCRIPTION

       The setclock() function sets a time value into the system-wide clock whose symbolic name is specified by the clktyp parameter,  which  must
       be TIMEOFDAY, defined in the sys/timers.h header file.

       The  source  of the current value of time set into the system-wide time-of-day clock by this function is stored in space reserved by a type
       timespec structure pointed to by the val parameter. This time information is the amount of time since the epoch. The epoch is referenced to
       00:00:00  GMT  (Greenwich Mean Time) 1 Jan 1970. The timespec structure, which is also defined in the sys/timers.h header file has the fol-
       lowing members:

       unsigned long	tv_sec	 Time of day since the epoch in seconds.
		long   tv_nsec	 Time  of  day	fraction  of  a   second
				 (expressed in nanoseconds).

NOTES

       Trial use

RETURN VALUES

       Upon  successful completion, the setclock() function returns a value of 0 (zero).  Otherwise, a value of -1 is returned and errno is set to
       indicate the error.

ERRORS

       If the setclock() function fails, errno may be set to one of the following values: The clktyp parameter does not specify  a  known  system-
       wide  clock, the information pointed to by the val parameter is outside the permissible range for the clock specified by the clktyp parame-
       ter, or a nanosecond value less than zero or greater than or equal to 1000 million is specified by the information pointed to  by  the  val
       parameter.  An error occurred while accessing the clock specified by the clktyp parameter.  The requesting process does not have the appro-
       priate privilege to set the clock specified by the clktyp parameter.

RELATED INFORMATION

       Functions: getclock(3), gettimer(3), time(3) delim off

																       setclock(3)

Check Out this Related Man Page

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)

Linux and UNIX Man Pages

setclock(3) [osf1 man page]

Check Out this Related Man Page