hardclock(9) - NetBSD Manual Pages

HARDCLOCK(9)           NetBSD Kernel Developer's Manual           HARDCLOCK(9)


NAME

     hardclock -- real-time timer


SYNOPSIS

     void
     hardclock(struct clockframe *);


DESCRIPTION

     The hardclock() function gets called hz(9) times per second.  It performs
     different tasks:
     ·   Run the current process's virtual and profile time (decrease the cor-
         responding timers, if they are activated, and generate SIGVTALRM or
         SIGPROF, respectively).
     ·   Increment the time-of-day, taking care of any ntpd(8) or adjtime(2)
         induced changes and leap seconds, as well as any necessary compensa-
         tions to keep in sync with PPS signals or external clocks, if support
         for this is in the kernel (see options(4)).
     ·   Schedule softclock interrupts if any callouts should be triggered
         (see callout(9)).


SEE ALSO

     adjtime(2), ntp_adjtime(2), signal(7), ntpd(8), callout(9), hz(9)

NetBSD 5.0                     September 5, 2001                    NetBSD 5.0