ADJFREQ(2) OpenBSD Programmer's Manual ADJFREQ(2)NAMEadjfreq - 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);
DESCRIPTIONadjfreq() 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
A return value of 0 indicates that the call succeeded. A return value of
-1 indicates that an error occurred, and in this case an error code is
stored in the global variable errno.
ERRORSadjfreq() 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 effective
user ID is not that of the superuser.
SEE ALSOdate(1), adjtime(2), gettimeofday(2), ntpd(8), timed(8), timedc(8)
R. Gusella and S. Zatti, TSP: The Time Synchronization Protocol for UNIX
4.3BSD.
HISTORY
The adjfreq() function call first appeared in OpenBSD 4.0.
OpenBSD 4.9 May 31, 2007 OpenBSD 4.9