clock_getres(2)               System Calls Manual              clock_getres(2)

<?><?><?><?><?><?><?><?><?><?><?><?>
       clock_getres, clock_gettime, clock_settime - <?><?><?><?><?><?><?>
       <?><?><?><?><?> <?> <?><?><?><?><?><?><?>

<?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?> C
       (libc, -lc), <?><?><?><?><?><?><?> <?> glibc 2.17

       <?><?> glibc 2.17, <?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?> (librt, -lrt)

<?><?><?><?><?>
       #include <time.h>

       int clock_getres(clockid_t clockid, struct timespec *_Nullable res);

       int clock_gettime(clockid_t clockid, struct timespec *tp);
       int clock_settime(clockid_t clockid, const struct timespec *tp);

   <?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?>
   <?><?><?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?> <?><?><?> glibc
   (<?><?>. feature_test_macros(7)):

       clock_getres(), clock_gettime(), clock_settime():
           _POSIX_C_SOURCE >= 199309L

<?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?> clock_getres() <?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?><?>
       (<?><?><?><?><?><?><?><?>) <?><?><?><?><?><?><?><?> <?> clockid
       <?><?><?><?><?>, <?>, <?><?><?><?> res <?><?> <?><?><?><?><?> NULL,
       <?><?><?><?><?><?><?><?><?> <?><?> <?> struct timespec,
       <?><?><?><?><?><?><?><?><?> <?> res. <?><?><?><?><?><?><?><?>
       <?><?><?><?><?> <?><?><?><?><?><?><?> <?><?>
       <?><?><?><?><?><?><?><?><?><?> <?> <?><?> <?><?><?><?><?> <?><?><?><?>
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       <?><?><?><?><?><?><?><?><?>. <?><?><?><?> <?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?>, <?><?><?><?><?><?><?><?><?> <?>
       <?><?><?><?><?><?><?><?><?> tp <?><?><?><?><?><?><?> clock_settime(),
       <?><?> <?><?><?><?><?><?> res, <?><?> <?><?><?>
       <?><?><?><?><?><?><?><?><?> <?><?> <?><?><?><?><?><?><?><?> res.

       <?><?><?><?><?><?><?> clock_gettime() <?> clock_settime()
       <?><?><?><?><?><?><?><?> <?> <?><?><?><?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?> <?><?><?><?><?><?><?><?><?> <?><?><?><?><?> clockid.

       <?><?><?><?><?><?><?><?><?> res <?> tp <?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?><?> timespec(3).

       <?><?><?><?><?><?><?><?> clockid <?><?><?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?><?><?><?>
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       <?><?><?><?> <?><?><?><?><?><?><?><?><?> <?><?><?>
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       <?><?><?><?> <?><?><?> <?><?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?> <?><?><?><?><?><?> <?> <?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?> <?><?><?><?><?><?><?><?>.

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       <?><?><?><?> <?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?>,
       <?><?><?><?><?><?><?> <?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?><?><?><?> CLOCK_REALTIME. <?><?>
       <?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?><?><?><?><?> <?>
       <?><?><?><?><?><?><?><?> <?> <?><?><?><?><?><?><?><?><?><?><?><?> <?>
       <?><?><?><?><?><?> <?><?><?><?><?>. <?><?><?><?><?> <?><?>
       <?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?>, <?><?>
       <?><?><?><?><?><?><?> <?> <?><?><?><?><?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?><?> <?><?><?> <?><?><?><?><?> <?><?>
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       <?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?> <?><?><?>.

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       <?><?><?><?><?> <?><?><?><?><?>.
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       <?><?><?><?><?><?><?> <?> <?><?><?><?><?><?><?> <?><?>
       <?><?><?><?><?><?><?> <?><?> <?><?><?><?><?><?><?><?><?><?>.

       <?> <?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?> glibc <?>
       <?><?><?><?> Linux <?><?><?><?><?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?> <?><?><?><?>:

       CLOCK_REALTIME
              A settable system-wide clock that measures real (i.e.,
              wall-clock) time.  Setting this clock requires appropriate
              privileges.  This clock is affected by discontinuous jumps in
              the system time (e.g., if the system administrator manually
              changes the clock), and by frequency adjustments performed by
              NTP and similar applications via adjtime(3), adjtimex(2),
              clock_adjtime(2), and ntp_adjtime(3).  This clock normally
              counts the number of seconds since 1970-01-01 00:00:00
              Coordinated Universal Time (UTC) except that it ignores leap
              seconds; near a leap second it is typically adjusted by NTP to
              stay roughly in sync with UTC.

       CLOCK_REALTIME_ALARM (<?><?><?><?><?><?><?> <?> Linux 3.0; <?><?><?><?>
       <?><?><?><?><?><?> <?> Linux)
              <?><?><?> CLOCK_REALTIME, <?><?> <?><?>
              <?><?><?><?><?><?><?><?><?><?><?><?><?>. <?><?>. timer_create(2)
              <?><?><?> <?><?><?><?><?><?><?><?><?><?><?><?><?><?>
              <?><?><?><?><?><?><?><?><?><?><?><?>.

       CLOCK_REALTIME_COARSE (<?><?><?><?><?><?><?> <?> Linux 2.6.32;
       <?><?><?><?> <?><?><?><?><?><?> <?> Linux)
              A faster but less precise version of CLOCK_REALTIME.  This clock
              is not settable.  Use when you need very fast, but not
              fine-grained timestamps.  Requires per-architecture support, and
              probably also architecture support for this flag in the vdso(7).

       CLOCK_TAI (<?><?><?><?><?><?><?> <?> Linux 3.10; <?><?><?><?>
       <?><?><?><?><?><?> <?> Linux)
              A nonsettable system-wide clock derived from wall-clock time but
              counting leap seconds.  This clock does not experience
              discontinuities or frequency adjustments caused by inserting
              leap seconds as CLOCK_REALTIME does.

              <?><?><?><?><?><?><?><?><?><?><?><?> TAI
              <?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?><?><?><?>
              <?><?><?><?><?><?><?> <?><?><?><?><?>.

       CLOCK_MONOTONIC
              A nonsettable system-wide clock that represents monotonic time
              since--as described by POSIX--"some unspecified point in the
              past".  On Linux, that point corresponds to the number of
              seconds that the system has been running since it was booted.

              The CLOCK_MONOTONIC clock is not affected by discontinuous jumps
              in the system time (e.g., if the system administrator manually
              changes the clock), but is affected by frequency adjustments.
              This clock does not count time that the system is suspended.
              All CLOCK_MONOTONIC variants guarantee that the time returned by
              consecutive calls will not go backwards, but successive calls
              may--depending on the architecture--return identical
              (not-increased) time values.

       CLOCK_MONOTONIC_COARSE (<?><?><?><?><?><?><?> <?> Linux 2.6.32;
       <?><?><?><?> <?><?><?><?><?><?> <?> Linux)
              <?><?><?><?><?> <?><?><?><?><?><?><?>, <?><?> <?><?><?><?><?>
              <?><?><?><?><?><?> <?><?><?><?><?><?> CLOCK_MONOTONIC.
              <?><?><?><?><?><?><?><?><?><?><?>, <?><?><?><?> <?><?><?><?><?>
              <?><?> <?><?><?><?><?> <?><?><?><?><?><?> <?><?><?><?><?>
              <?><?><?><?><?><?><?>, <?><?> <?><?><?><?><?>
              <?><?><?><?><?><?>. <?><?><?><?><?><?><?><?><?>
              <?><?><?><?><?><?><?><?><?> <?>
              <?><?><?><?><?><?><?><?><?><?><?> <?>, <?><?><?><?><?><?><?><?>,
              <?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?><?><?>
              <?><?><?><?><?> <?><?><?><?><?> <?> vdso(7).

       CLOCK_MONOTONIC_RAW (<?><?><?><?><?><?><?> <?> Linux 2.6.28;
       <?><?><?><?> <?><?><?><?><?><?> <?> Linux)
              Similar to CLOCK_MONOTONIC, but provides access to a raw
              hardware-based time that is not subject to frequency
              adjustments.  This clock does not count time that the system is
              suspended.

       CLOCK_BOOTTIME (<?><?><?><?><?><?><?> <?> Linux 2.6.39; <?><?><?><?>
       <?><?><?><?><?><?> <?> Linux)
              A nonsettable system-wide clock that is identical to
              CLOCK_MONOTONIC, except that it also includes any time that the
              system is suspended.  This allows applications to get a
              suspend-aware monotonic clock without having to deal with the
              complications of CLOCK_REALTIME, which may have discontinuities
              if the time is changed using settimeofday(2)  or similar.

       CLOCK_BOOTTIME_ALARM (<?><?><?><?><?><?><?> <?> Linux 3.0; <?><?><?><?>
       <?><?><?><?><?><?> <?> Linux)
              <?><?><?> CLOCK_BOOTTIME. <?><?><?><?><?><?><?><?><?><?><?>
              <?><?>. <?> timer_create(2).

       CLOCK_PROCESS_CPUTIME_ID (<?><?><?><?><?><?><?> <?> Linux 2.6.12)
              This is a clock that measures CPU time consumed by this process
              (i.e., CPU time consumed by all threads in the process).  On
              Linux, this clock is not settable.

       CLOCK_THREAD_CPUTIME_ID (<?><?><?><?><?><?><?> <?> Linux 2.6.12)
              <?><?><?> <?><?><?><?>, <?><?><?><?><?><?><?>
              <?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?><?><?>
              <?><?><?><?><?>, <?><?><?><?><?><?><?><?><?><?><?><?>
              <?><?><?><?> <?><?><?><?><?><?><?>. <?> Linux <?><?><?>
              <?><?><?><?> <?><?> <?><?><?><?><?> <?><?><?><?>
              <?><?><?><?><?><?><?><?><?><?><?>.

       Linux <?><?><?><?><?> <?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?>, <?><?><?> <?><?><?><?><?><?><?> <?><?><?><?>.

   <?><?><?><?><?><?><?><?><?><?><?><?> <?><?><?><?>
       In addition to the hard-coded System-V style clock IDs described above,
       Linux also supports POSIX clock operations on certain character
       devices.  Such devices are called "dynamic" clocks, and are supported
       since Linux 2.6.39.

       Using the appropriate macros, open file descriptors may be converted
       into clock IDs and passed to clock_gettime(), clock_settime(), and
       clock_adjtime(2).  The following example shows how to convert a file
       descriptor into a dynamic clock ID.

           #define CLOCKFD 3
           #define FD_TO_CLOCKID(fd)   ((~(clockid_t) (fd) << 3) | CLOCKFD)
           #define CLOCKID_TO_FD(clk)  ((unsigned int) ~((clk) >> 3))

           struct timespec ts;
           clockid_t clkid;
           int fd;

           fd = open("/dev/ptp0", O_RDWR);
           clkid = FD_TO_CLOCKID(fd);
           clock_gettime(clkid, &ts);

<?><?><?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?>
       clock_gettime(), clock_settime(), and clock_getres()  return 0 for
       success.  On error, -1 is returned and errno is set to indicate the
       error.

<?><?><?><?><?><?>
       EACCES clock_settime() <?><?> <?><?><?><?><?>
              <?><?><?><?><?><?><?><?><?><?> <?><?> <?><?><?><?><?><?>
              <?><?><?> <?><?><?><?><?><?><?><?><?><?>
              <?><?><?><?><?><?><?><?><?><?><?><?><?>
              <?><?><?><?><?><?><?><?><?><?> POSIX <?><?><?><?><?>.

       EFAULT tp <?><?><?><?><?><?><?><?><?> <?><?> <?><?><?><?><?><?><?>
              <?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?>
              <?><?><?><?><?><?><?><?><?><?><?><?>.

       EINVAL The clockid specified is invalid for one of two reasons.  Either
              the System-V style hard coded positive value is out of range, or
              the dynamic clock ID does not refer to a valid instance of a
              clock object.

       EINVAL (clock_settime()): tp.tv_sec is negative or tp.tv_nsec is
              outside the range [0, 999,999,999].

       EINVAL clockid, <?><?><?><?><?><?><?><?><?> <?> <?><?><?><?><?><?>
              clock_settime(), <?><?> <?><?><?><?><?><?><?><?>
              <?><?><?><?><?><?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?>.

       EINVAL (<?><?><?><?><?><?><?> <?> Linux 4.3)
              <?><?><?><?><?> clock_settime() <?><?>
              <?><?><?><?><?><?><?><?><?> clockid <?><?><?><?><?><?>
              CLOCK_REALTIME <?><?><?> <?><?><?><?><?><?><?><?><?>
              <?><?><?><?><?><?><?> <?> <?><?><?><?><?><?><?><?>
              <?><?><?><?><?><?> <?><?><?><?><?><?><?><?>
              <?><?><?><?><?><?><?><?> <?><?><?><?><?> CLOCK_MONOTONIC.

       ENODEV The hot-pluggable device (like USB for example) represented by a
              dynamic clk_id has disappeared after its character device was
              opened.

       ENOTSUP
              <?><?><?><?><?><?><?><?> <?><?>
              <?><?><?><?><?><?><?><?><?><?><?><?><?><?>
              <?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?><?><?>
              <?><?><?><?><?><?><?><?><?><?><?>
              <?><?><?><?><?><?><?><?><?><?><?><?><?> POSIX.

       EOVERFLOW
              The timestamp would not fit in time_t range.  This can happen if
              an executable with 32-bit time_t is run on a 64-bit kernel when
              the time is 2038-01-19 03:14:08 UTC or later.  However, when the
              system time is out of time_t range in other situations, the
              behavior is undefined.

       EPERM  <?><?><?> <?><?><?><?><?><?><?><?><?>
              <?><?><?><?><?><?><?><?><?> <?><?><?><?><?> <?>
              <?><?><?><?><?><?><?> clock_settime()
              <?><?><?><?><?><?><?><?><?><?><?><?> <?><?><?><?>.

<?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?> <?> attributes(7).

       +----------------------------+----------------------------------------------------------+--------------------------+
       |<?><?><?><?><?><?><?><?><?> | <?><?><?><?><?><?><?>                                    | <?><?><?><?><?><?><?><?> |
       +----------------------------+----------------------------------------------------------+--------------------------+
       |clock_getres(),             | <?><?><?><?><?><?><?><?><?><?><?><?> <?> <?><?><?><?><?> | MT-Safe                  |
       |clock_gettime(),            |                                                          |                          |
       |clock_settime()             |                                                          |                          |
       +----------------------------+----------------------------------------------------------+--------------------------+
<?><?><?><?><?><?>
       <?> POSIX.1 <?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?>:

              <?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?>
              <?><?><?><?><?> CLOCK_REALTIME <?> <?><?><?><?><?><?><?>
              clock_settime() <?><?> <?><?><?><?><?><?><?><?><?>
              <?><?><?><?><?><?><?> <?><?> <?><?><?><?>, <?><?><?><?><?><?><?>
              <?><?><?><?><?><?><?><?><?> <?> <?><?><?><?><?><?><?><?><?>
              <?><?><?><?><?><?><?> <?><?>-<?><?> <?><?><?><?><?>,
              <?><?><?><?><?><?> <?><?><?><?><?><?><?>
              <?><?><?><?><?><?><?><?> <?><?> <?><?><?><?> <?><?><?><?><?>,
              <?><?><?><?><?><?><?> <?><?><?><?><?><?><?> nanosleep();
              <?><?><?><?><?>, <?><?><?> <?><?> <?><?><?><?><?><?><?><?><?>
              <?><?><?><?><?><?><?> <?><?>
              <?><?><?><?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?>,
              <?><?><?><?><?><?><?><?><?><?><?><?><?><?> <?><?> <?><?><?><?>
              <?><?><?><?><?>. <?> <?><?><?><?><?><?><?><?><?><?>,
              <?><?><?><?><?><?><?><?> <?><?><?><?><?><?> <?><?><?><?><?>
              <?><?><?><?><?><?><?>, <?><?><?><?><?> <?><?><?><?><?><?><?>
              <?><?><?><?><?><?><?><?><?><?><?>
              <?><?><?><?><?><?><?><?><?><?><?><?><?>
              <?><?><?><?><?><?><?><?>, <?><?><?><?><?><?><?><?><?><?> <?><?>
              <?><?><?><?><?><?> <?><?><?> <?><?><?><?><?><?><?>
              <?><?><?><?><?><?><?><?> <?><?><?><?><?>.

       <?><?><?><?><?><?><?><?> POSIX.1-2001, <?><?><?><?><?><?><?> <?>
       <<<?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?>>> <?><?><?><?><?> <?><?><?><?><?><?><?><?><?>
       <?><?><?><?> CLOCK_PROCESS_CPUTIME_ID <?> CLOCK_THREAD_CPUTIME_ID <?>
       <?><?><?><?><?><?><?> clock_settime(). <?> Linux <?><?><?> <?><?><?><?>
       <?><?> <?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?> (<?>.
       <?>., <?><?><?><?><?><?><?> <?><?> <?><?><?><?><?> <?><?><?><?><?>
       <<<?><?><?><?><?><?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?>>>).

   <?><?><?><?><?><?><?> <?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?><?> C
       <?> <?><?><?><?><?>
       <?><?> <?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?> clock_gettime()
       <?><?><?><?><?><?><?><?><?> <?> vdso(7).

<?><?><?><?><?><?><?><?><?>
       POSIX.1-2008.

<?><?><?><?><?><?><?>
       POSIX.1-2001, SUSv2.  Linux 2.6.

       On POSIX systems on which these functions are available, the symbol
       _POSIX_TIMERS is defined in <unistd.h> to a value greater than 0.
       POSIX.1-2008 makes these functions mandatory.

       The symbols _POSIX_MONOTONIC_CLOCK, _POSIX_CPUTIME,
       _POSIX_THREAD_CPUTIME indicate that CLOCK_MONOTONIC,
       CLOCK_PROCESS_CPUTIME_ID, CLOCK_THREAD_CPUTIME_ID are available.  (See
       also sysconf(3).)

   <?><?><?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?> <?><?>
       <?><?><?><?><?><?><?><?> SMP
       <?><?> <?><?><?><?>, <?><?><?> <?> Linux <?><?><?><?>
       <?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?>
       CLOCK_PROCESS_CPUTIME_ID <?> CLOCK_THREAD_CPUTIME_ID,
       <?><?><?><?><?><?><?><?><?><?> <?><?><?><?> <?><?><?><?><?> <?> glibc
       <?><?> <?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?> <?><?> (TSC <?><?> i386, AR.ITC <?><?> Itanium).
       <?><?><?> <?><?><?><?><?><?><?><?> <?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?> <?> <?><?><?><?><?><?> <?><?> <?>,
       <?><?><?> <?><?><?><?><?><?><?><?><?>, <?><?><?> <?><?><?><?>
       <?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?>,
       <?><?><?><?> <?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?> <?><?> <?><?><?><?><?><?> <?><?>.

       <?><?><?><?> <?><?><?><?><?><?><?><?><?><?> <?>
       <?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?>,
       <?><?> <?><?><?> <?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?> <?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?>, <?><?><?>
       <?><?><?> <?><?><?><?><?><?> <?><?> <?><?><?><?><?>
       <?><?><?><?><?><?><?><?> <?><?> <?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?>. <?>
       <?><?><?><?> <?><?><?><?><?><?> clock_getcpuclockid(0)
       <?><?><?><?><?><?> ENOENT, <?><?><?><?><?> <?><?><?><?><?><?><?> <?><?>
       <?><?><?> <?><?><?><?><?><?><?><?><?>. <?><?><?><?> <?><?><?><?><?> <?>
       <?><?><?><?> <?><?><?><?><?><?> <?><?><?><?><?> <?><?><?><?><?><?><?>,
       <?><?><?><?><?><?> <?><?><?><?> <?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?>, <?><?><?> <?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?> <?><?> <?><?><?><?><?><?><?><?><?><?><?><?>
       <?><?>.

       The processors in an SMP system do not start all at exactly the same
       time and therefore the timer registers are typically running at an
       offset.  Some architectures include code that attempts to limit these
       offsets on bootup.  However, the code cannot guarantee to accurately
       tune the offsets.  glibc contains no provisions to deal with these
       offsets (unlike the Linux Kernel).  Typically these offsets are small
       and therefore the effects may be negligible in most cases.

       <?><?><?><?><?><?><?> <?> glibc 2.4, <?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?>, <?><?><?><?><?><?><?><?><?> <?><?> <?><?><?><?>
       <?><?><?><?><?><?><?><?>, <?><?> <?><?><?><?><?> <?><?><?><?><?>
       <?><?><?><?><?><?><?>, <?><?><?> <?><?><?>
       <?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?> CLOCK_PROCESS_CPUTIME_ID <?>
       CLOCK_THREAD_CPUTIME_ID (<?> <?><?><?><?><?><?><?><?>,
       <?><?><?><?><?><?><?> <?><?> <?><?><?><?><?><?><?><?><?><?><?><?><?>,
       <?><?> <?><?><?><?> Linux 2.6.12 <?> <?><?><?><?><?>).

<?><?><?><?><?><?><?>
       The program below demonstrates the use of clock_gettime()  and
       clock_getres()  with various clocks.  This is an example of what we
       might see when running the program:

           $ ./clock_times x
           CLOCK_REALTIME : 1585985459.446 (18356 days +  7h 30m 59s)
                resolution:          0.000000001
           CLOCK_TAI      : 1585985496.447 (18356 days +  7h 31m 36s)
                resolution:          0.000000001
           CLOCK_MONOTONIC:      52395.722 (14h 33m 15s)
                resolution:          0.000000001
           CLOCK_BOOTTIME :      72691.019 (20h 11m 31s)
                resolution:          0.000000001

   <?><?><?><?><?><?><?><?> <?><?><?> <?><?><?><?><?><?><?><?><?>
       /* clock_times.c

          Licensed under GNU General Public License v2 or later.
       */
       #define _XOPEN_SOURCE 600
       #include <stdbool.h>
       #include <stdint.h>
       #include <stdio.h>
       #include <stdlib.h>
       #include <time.h>

       #define SECS_IN_DAY (24 * 60 * 60)

       static void
       displayClock(clockid_t clock, const char *name, bool showRes)
       {
           long             days;
           struct timespec  ts;

           if (clock_gettime(clock, &ts) == -1) {
               perror("clock_gettime");
               exit(EXIT_FAILURE);
           }

           printf("%-15s: %10jd.%03ld (", name,
                  (intmax_t) ts.tv_sec, ts.tv_nsec / 1000000);

           days = ts.tv_sec / SECS_IN_DAY;
           if (days > 0)
               printf("%ld days + ", days);

           printf("%2dh %2dm %2ds",
                  (int) (ts.tv_sec % SECS_IN_DAY) / 3600,
                  (int) (ts.tv_sec % 3600) / 60,
                  (int) ts.tv_sec % 60);
           printf(")\n");

           if (clock_getres(clock, &ts) == -1) {
               perror("clock_getres");
               exit(EXIT_FAILURE);
           }

           if (showRes)
               printf("     resolution: %10jd.%09ld\n",
                      (intmax_t) ts.tv_sec, ts.tv_nsec);
       }

       int
       main(int argc, char *argv[])
       {
           bool showRes = argc > 1;

           displayClock(CLOCK_REALTIME, "CLOCK_REALTIME", showRes);
       #ifdef CLOCK_TAI
           displayClock(CLOCK_TAI, "CLOCK_TAI", showRes);
       #endif
           displayClock(CLOCK_MONOTONIC, "CLOCK_MONOTONIC", showRes);
       #ifdef CLOCK_BOOTTIME
           displayClock(CLOCK_BOOTTIME, "CLOCK_BOOTTIME", showRes);
       #endif
           exit(EXIT_SUCCESS);
       }

<?><?><?><?><?><?><?><?> <?><?><?><?><?>
       date(1), gettimeofday(2), settimeofday(2), time(2), adjtime(3),
       clock_getcpuclockid(3), ctime(3), ftime(3), pthread_getcpuclockid(3),
       sysconf(3), timespec(3), time(7), time_namespaces(7), vdso(7),
       hwclock(8)

<?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?> <?><?><?><?><?><?><?> <?><?><?><?>
       <?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?>(<?>) Azamat Hackimov
       <azamat.hackimov@gmail.com>, Dmitriy S. Seregin <dseregin@59.ru>,
       Dmitry Bolkhovskikh <d20052005@yandex.ru>, Katrin Kutepova
       <blackkatelv@gmail.com>, Yuri Kozlov <yuray@komyakino.ru>, <?><?><?><?>
       <?><?><?><?><?><?> <pavia00@gmail.com> <?> Kirill Rekhov
       <krekhov.dev@gmail.com>

       <?><?><?><?> <?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?><?><?><?>; <?><?>
       <?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?> <?><?>
       <?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?> GNU (GNU General Public License - GPL,
       <https://www.gnu.org/licenses/gpl-3.0.html> <?><?><?><?><?><?> 3
       <?><?><?> <?><?><?><?><?> <?><?><?><?><?><?><?>) <?>
       <?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?>, <?><?> <?><?><?> <?><?><?><?><?>-<?><?><?><?>
       <?><?><?><?><?><?><?><?>.

       <?><?><?><?> <?><?> <?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?>-<?><?><?><?> <?><?><?><?><?><?> <?>
       <?><?><?><?><?><?><?><?> <?><?><?><?> <?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?><?>, <?><?><?><?><?><?><?><?><?><?>,
       <?><?><?><?><?><?><?><?> <?><?> <?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?><?><?>(<?><?>) <?><?> <?><?><?>(<?><?>)
       <?><?><?><?><?><?>(<?><?>) <?><?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?> <?><?><?> <?><?> <?><?><?><?><?><?> <?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?><?><?>
       <<debian-l10n-russian@lists.debian.org>>.

<?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?> Linux 6.9.1
                           15 <?><?><?><?> 2024 <?>.           clock_getres(2)