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       ntp_gettime, ntp_gettimex  - get time parameters (NTP daemon interface)


       #include <sys/timex.h>

       int ntp_gettime(struct ntptimeval *ntv);
       int ntp_gettimex(struct ntptimeval *ntv);


       Both  of  these APIs return information to the caller via the ntv argument, a structure of
       the following type:

           struct ntptimeval {
               struct timeval time;    /* Current time */
               long maxerror;          /* Maximum error */
               long esterror;          /* Estimated error */
               long tai;               /* TAI offset */

               /* Further padding bytes allowing for future expansion */

       The fields of this structure are as follows:

       time   The current time, expressed as a timeval structure:

                  struct timeval {
                      time_t      tv_sec;   /* Seconds since the Epoch */
                      suseconds_t tv_usec;  /* Microseconds */

              Maximum error, in microseconds.  This value can be initialized  by  ntp_adjtime(3),
              and  is  increased periodically (on Linux: each second), but is clamped to an upper
              limit (the kernel constant NTP_PHASE_MAX, with a value of 16,000).

              Estimated error, in microseconds.  This value can  be  set  via  ntp_adjtime(3)  to
              contain  an  estimate of the difference between the system clock and the true time.
              This value is not used inside the kernel.

       tai    TAI (Atomic International Time) offset.

       ntp_gettime() returns an ntptimeval structure in which the time,  maxerror,  and  esterror
       fields are filled in.

       ntp_gettimex()  performs  the  same task as ntp_gettime(), but also returns information in
       the tai field.


       The return values for ntp_gettime() and ntp_gettimex() are as for  adjtimex(2).   Given  a
       correct pointer argument, these functions always succeed.


       The  ntp_gettime()  function is available since glibc 2.1.  The ntp_gettimex() function is
       available since glibc 2.12.


       For an explanation of the terms used in this section, see attributes(7).

       │InterfaceAttributeValue   │
       │ntp_gettime(), ntp_gettimex()                                  │ Thread safety │ MT-Safe │


       ntp_gettime()  is  described  in   the   NTP   Kernel   Application   Program   Interface.
       ntp_gettimex() is a GNU extension.


       adjtimex(2), ntp_adjtime(3), time(7)

       NTP "Kernel Application Program Interface" ⟨


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