Updated: 2021/Apr/14


TIME_SECOND(9)             Kernel Developer's Manual            TIME_SECOND(9)

NAME
     time_second, time_uptime - system time variables

SYNOPSIS
     #include <sys/time.h>

     extern time_t time_second;
     extern time_t time_uptime;

DESCRIPTION
     The time_second variable is the system's "wall time" clock.  It is set at
     boot by inittodr(9), and is updated periodically via timecounter(9)
     framework, and also updated by the settimeofday(2) system call.

     The time_uptime variable is a monotonically increasing system clock.  It
     is set at boot, and is updated periodically.  (It is not updated by
     settimeofday(2).)

     All of these variables contain times expressed in seconds since midnight
     (0 hour), January 1, 1970, UTC.

     The bintime(9), getbintime(9), microtime(9), getmicrotime(9),
     nanotime(9), and getnanotime(9) functions can be used to get the current
     time more accurately and in an atomic manner.

     Similarly, the binuptime(9), getbinuptime(9), microuptime(9),
     getmicrouptime(9), nanouptime(9), and getnanouptime(9) functions can be
     used to get the time elapsed since boot more accurately and in an atomic
     manner.

SEE ALSO
     clock_settime(2), ntp_adjtime(2), timespec(3), hardclock(9), hz(9)

NetBSD 9.99                     April 17, 2020                     NetBSD 9.99