개요

• 솔라나라에 설명된 어플리케이션에 대해 맨 페이지를 찾아 출력한다.
• MAN 페이지에 대한 설명은 윈디하나의 솔라나라: MAN 페이지을 참고하자.
• svcadm(1M)을 검색하려면 섹션에서 1M 을 선택하고, 맨 페이지 이름에 svcadm을 입력하고 검색을 누른다.

ntp_gettime(3)

NTP_GETTIME(3)             Linux Programmer's Manual            NTP_GETTIME(3)



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

SYNOPSIS
       #include <sys/timex.h>

       int ntp_gettime(struct ntptimeval *ntv);

       int ntp_gettimex(struct ntptimeval *ntv);

DESCRIPTION
       Both  of  these APIs return information to the caller via the ntv argu‐
       ment, a structure of the following type:

           struct ntptimeval {
               struct timeval time;        /* Current time */
               long int maxerror;          /* Maximum error */
               long int esterror;          /* Estimated error */
               long int 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 */
                  };

       maxerror
              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).

       esterror
              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, maxer‐
       ror, and esterror fields are filled in.

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

RETURN VALUE
       The return values for ntp_gettime() and ntp_gettimex() are as for  adj‐
       timex(2).   Given  a  correct  pointer argument, these functions always
       succeed.

VERSIONS
       The ntp_gettime() function is available since glibc 2.1.  The  ntp_get‐
       timex() function is available since glibc 2.12.

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

       allbox; lbw30 lb lb l l l.  Interface Attribute Value T{ ntp_gettime(),
       ntp_gettimex() T}   Thread safety  MT-Safe

CONFORMING TO
       ntp_gettime() is described in the NTP Kernel Application Program Inter‐
       face.  ntp_gettimex() is a GNU extension.

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

       NTP "Kernel Application Program Interface"
       ⟨http://www.slac.stanford.edu/comp/unix/package/rtems/src/ssrlApps/
       ntpNanoclock/api.htm⟩

COLOPHON
       This page is part of release 5.02 of the Linux man-pages project.  A
       description of the project, information about reporting bugs, and the
       latest version of this page, can be found at
       https://www.kernel.org/doc/man-pages/.



Linux                             2017-09-15                    NTP_GETTIME(3)