Manual browser: nanouptime(9)
|MICROUPTIME(9)||Kernel Developer's Manual||MICROUPTIME(9)|
NAMEbinuptime, getbinuptime, microuptime, getmicrouptime, nanouptime, getnanouptime — get the time elapsed since boot
binuptime(struct bintime *bt);
getbinuptime(struct bintime *bt);
microuptime(struct timeval *tv);
getmicrouptime(struct timeval *tv);
nanouptime(struct timespec *ts);
getnanouptime(struct timespec *tsp);
DESCRIPTIONThe binuptime() and getbinuptime() functions store the time elapsed since boot as a struct bintime at the address specified by bt. The microuptime() and getmicrouptime() functions perform the same utility, but record the elapsed time as a struct timeval instead. Similarly the nanouptime() and getnanouptime() functions store the elapsed time as a struct timespec. The used structures are described in timeval(3).
The binuptime(), microuptime(), and nanouptime() functions always query the timecounter to return the current time as precisely as possible. Whereas getbinuptime(), getmicrouptime(), and getnanouptime() functions are abstractions which return a less precise, but faster to obtain, time.
The intent of the getbinuptime(), getmicrouptime(), and getnanouptime() functions is to enforce the user's preference for timer accuracy versus execution time. They should be used where a precision of 1/HZ (e.g., 10 msec on a 100HZ machine, see hz(9)) is acceptable or where performance is priority.
SEE ALSOmicrotime(9), timecounter(9), tvtohz(9)
AUTHORSThis manual page was written by <email@example.com>.
|June 8, 2010||NetBSD 7.0|