svcadm(8)을 검색하려면 섹션에서 8 을 선택하고, 맨 페이지 이름에 svcadm을 입력하고 검색을 누른다.
adjtime(2)
adjtime(2) System Calls adjtime(2)
NAME
adjtime - correct the time to allow synchronization of the system clock
SYNOPSIS
#include <sys/time.h>
int adjtime(struct timeval *delta, struct timeval *olddelta);
DESCRIPTION
The adjtime() function adjusts the system's notion of the current time
as returned by gettimeofday(3C), advancing or retarding it by the
amount of time specified in the struct timeval pointed to by delta.
The adjustment is effected by speeding up (if that amount of time is
positive) or slowing down (if that amount of time is negative) the sys‐
tem's clock by some small percentage, generally a fraction of one per‐
cent. The time is always a monotonically increasing function. A time
correction from an earlier call to adjtime() may not be finished when
adjtime() is called again.
If delta is 0, then olddelta returns the status of the effects of the
previous adjtime() call with no effect on the time correction as a re‐
sult of this call. If olddelta is not a null pointer, then the struc‐
ture it points to will contain, upon successful return, the number of
seconds and/or microseconds still to be corrected from the earlier
call. If olddelta is a null pointer, the corresponding information will
not be returned.
This call may be used in time servers that synchronize the clocks of
computers in a local area network. Such time servers would slow down
the clocks of some machines and speed up the clocks of others to bring
them to the average network time.
Only a process with the {PRIV_SYS_TIME} privilege can adjust the time
of day.
The adjustment value will be silently rounded to the resolution of the
system clock.
RETURN VALUES
Upon successful completion, adjtime() returns 0. Otherwise, it returns
−1 and sets errno to indicate the error.
ERRORS
The adjtime() function will fail if:
EFAULT The delta or olddelta argument points outside the process's
allocated address space, or olddelta points to a region of
the process's allocated address space that is not writable.
EINVAL The tv_usec member of delta is not within valid range
(−1000000 to 1000000).
EPERM The {PRIV_SYS_TIME} privilege is not asserted in the effec‐
tive set of the calling process.
ENOTSUP This system call is not supported if calling process belongs
to a non-global zone which is only allowed to set the zone-
specific time. See zonecfg(8), global-time property for more
information.
Additionally, the adjtime() function will fail for 32-bit processes if:
EOVERFLOW The size of the tv_sec member of the timeval structure
pointed to by olddelta is too small to contain the correct
number of seconds.
ATTRIBUTES
See attributes(7) for descriptions of the following attributes:
tab() box; cw(2.75i) |cw(2.75i) lw(2.75i) |lw(2.75i) ATTRIBUTE TYPEAT‐
TRIBUTE VALUE _ Interface StabilityCommitted _ StandardNone
SEE ALSO
date(1), ntp_adjtime(2), gettimeofday(3C), privileges(7), zonecfg(8)
HISTORY
The adjtime() function has been included in all Sun and Oracle releases
of Solaris.
Oracle Solaris 11.4 30 Jan 2023 adjtime(2)