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MICROTIME(9) FreeBSD Kernel Developer's Manual MICROTIME(9)
NAME
bintime, getbintime, microtime, getmicrotime, nanotime, getnanotime - get
the current time
SYNOPSIS
#include <sys/time.h>
void
bintime(struct bintime *bt);
void
getbintime(struct bintime *bt);
void
microtime(struct timeval *tv);
void
getmicrotime(struct timeval *tv);
void
nanotime(struct timespec *ts);
void
getnanotime(struct timespec *tsp);
DESCRIPTION
The bintime() and getbintime() functions store the system time as a
struct bintime at the addresses specified by bt. The microtime() and
getmicrotime() functions perform the same utility, but record the time as
a struct timeval instead. Similarly the nanotime() and getnanotime()
functions store the time as a struct timespec.
The bintime(), microtime(), and nanotime() functions always query the
timecounter to return the current time as precisely as possible. Whereas
getbintime(), getmicrotime(), and getnanotime() functions are
abstractions which return a less precise, but faster to obtain, time.
The intent of the getbintime(), getmicrotime(), and getnanotime()
functions is to enforce the user's preference for timer accuracy versus
execution time.
SEE ALSO
binuptime(9), getbinuptime(9), getmicrouptime(9), getnanouptime(9),
microuptime(9), nanouptime(9), tvtohz(9)
HISTORY
The bintime functions first appeared in FreeBSD 5.0. The microtime and
nanotime functions first appeared in FreeBSD 3.0 but have existed in
other incarnations since 4.4BSD.
AUTHORS
This manual page was written by Kelly Yancey <kbyanc@posi.net>.
FreeBSD 14.0-RELEASE-p6 September 16, 2004 FreeBSD 14.0-RELEASE-p6