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NTP_GETTIME(2)           DragonFly System Calls Manual          NTP_GETTIME(2)


NAME

     ntp_gettime -- NTP user application interface


LIBRARY

     Standard C Library (libc, -lc)


SYNOPSIS

     #include <sys/timex.h>

     int
     ntp_gettime(struct ntptimeval *ntv);


DESCRIPTION

     The time returned by ntp_gettime() is in a timespec structure, but may be
     in either microsecond (seconds and microseconds) or nanosecond (seconds
     and nanoseconds) format.  The particular format in use is determined by
     the STA_NANO bit of the status word returned by the ntp_adjtime() system
     call.  ntp_gettime() has as argument a pointer to the ntptimeval struc-
     ture with the following members:

     struct ntptimeval {
             struct timespec time;   /* current time (ns) (ro) */
             long maxerror;          /* maximum error (us) (ro) */
             long esterror;          /* estimated error (us) (ro) */
             long tai;               /* TAI offset */
             int time_state;         /* time status */
     };

     These are understood as:

     time        Current time (read-only).

     maxerror    Maximum error in microseconds (read-only).

     esterror    Estimated error in microseconds (read-only).

     tai         Temps Atomique International (French for International Atomic
                 Time), measures real time.  Used for acute time measurements.

     time_state  Current time status.


RETURN VALUES

     The ntp_gettime() function returns the value 0 if successful; otherwise
     the value -1 is returned and the global variable errno is set to indicate
     the error.

     Possible states of the clock are:

     TIME_OK     Everything okay, no leap second warning.
     TIME_INS    Insert leap second warning.
     TIME_DEL    Delete leap second warning.
     TIME_OOP    Leap second in progress.
     TIME_WAIT   Leap second has occurred.
     TIME_ERROR  Clock not synchronized.


SEE ALSO

     ntp_adjtime(2), ntpd(8) (net/openntpd)


AUTHORS

     This manual page was written by Tom Rhodes <trhodes@FreeBSD.org>.

DragonFly 3.5                    April 1, 2003                   DragonFly 3.5

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