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man pages section 2: System Calls

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Updated: Wednesday, July 27, 2022



ntp_gettime - get local clock values


#include <sys/timex.h>

int ntp_gettime(struct ntptimeval *tptr);


The ntp_gettime() function reads the local clock value and dispersion, returning the information in tptr.

The ntptimeval structure contains the following members:

struct ntptimeval {
    struct timeval   time;       /* current time (ro) */
    int32_t          maxerror;   /* maximum error (us) (ro) */
    int32_t          esterror;   /* estimated error (us) (ro) */

Return Values

Upon successful completion, ntp_gettime() returns the current clock state (see <sys/timex.h>). Otherwise, it returns −1 and sets errno to indicate the error.


The ntp_gettime() function will fail if:


The tptr argument points to an invalid address.

The ntp_gettime() function will fail for 32-bit interfaces if:


The size of the time.tv_sec member of the ntptimeval structure pointed to by tptr is too small to contain the correct number of seconds.

See Also

ntpd(8), ntp_adjtime(2)