The current time of the system's monotonic clock. This has no relation
to the wall clock time, as the wall clock time can be adjusted (e.g.
by NTP), whereas the monotonic clock always moves forward. The source
of the monotonic time is system-specific.
On Windows, QueryPerformanceCounter is used. On Mac OS X,
mach_absolute_time is used, while on other POSIX systems,
clock_gettime is used.
Warning: On some systems, the monotonic clock may stop counting
when the computer goes to sleep or hibernates. So, the
monotonic clock may indicate less time than has actually
passed if that occurs. This is known to happen on
Mac OS X. It has not been tested whether it occurs on
either Windows or Linux.
The current time of the system's monotonic clock. This has no relation to the wall clock time, as the wall clock time can be adjusted (e.g. by NTP), whereas the monotonic clock always moves forward. The source of the monotonic time is system-specific.
On Windows, QueryPerformanceCounter is used. On Mac OS X, mach_absolute_time is used, while on other POSIX systems, clock_gettime is used.
Warning: On some systems, the monotonic clock may stop counting when the computer goes to sleep or hibernates. So, the monotonic clock may indicate less time than has actually passed if that occurs. This is known to happen on Mac OS X. It has not been tested whether it occurs on either Windows or Linux.