Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages

  
 
  

home | help
ADJFREQ(2)		  FreeBSD System Calls Manual		    ADJFREQ(2)

NAME
     adjfreq --	correct	the rate of the	system clock

SYNOPSIS
     #include <sys/types.h>
     #include <sys/time.h>

     int
     adjfreq(const int64_t *freq, int64_t *oldfreq);

DESCRIPTION
     adjfreq() adjusts the rate	in which time progresses if freq is non-null.
     The unit of the rate of adjustment	is nanoseconds per second, shifted
     left 32 bits to allow for fractional values.

     If	oldfreq	is non-null, the current value is returned.

     Only the superuser	may adjust the frequency.

RETURN VALUES
     Upon successful completion, the value 0 is	returned; otherwise the
     value -1 is returned and the global variable errno	is set to indicate the
     error.

ERRORS
     adjfreq() will fail if:

     [EFAULT]		Either of the arguments	point outside the process's
			allocated address space.

     [EPERM]		The freq argument is non-null and the process's	effec-
			tive user ID is	not that of the	superuser.

     [EINVAL]		freq is	less than -500000 ppm or greater than 500000
			ppm.

SEE ALSO
     date(1), adjtime(2), gettimeofday(2), ntpd(8)

HISTORY
     The adjfreq() function call first appeared	in OpenBSD 4.0.

FreeBSD	13.0			 July 9, 2020			  FreeBSD 13.0

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUES | ERRORS | SEE ALSO | HISTORY

Want to link to this manual page? Use this URL:
<https://www.freebsd.org/cgi/man.cgi?query=adjfreq&sektion=2&manpath=OpenBSD+6.9>

home | help