Clock_gettime(), clock_settime() and clock_getres() return 0 for success, or -1 for failure (in which case errno is set appropriately). Errors EFAULT tp points outside the accessible address space. EINVAL The clk_id specified is not supported on this system. EPERM clock_settime() does not have permission to set the clock indicated. Note Most systems require the program be linked with the librt library to use these functions. NOTE for SMP systems The CLOCK_PROCESS_CPUTIME_ID and CLOCK_THREAD_CPUTIME_ID clocks are realized on many platforms using timers from the CPUs (TSC on i386, AR.ITC on Itanium). These registers may differ between CPUs and as a consequence these clocks may return bogus results if a process is migrated to another CPU. If the CPUs in an SMP system have different clock sources then there is no way to maintain a correlation between the timer registers since each CPU will run at a slightly different frequency. If that is the case then clock_getcpuclockid(0) will return ENOENT to signify this condition. The two clocks will then only be useful if it can be ensured that a process stays on a certain CPU. ![]() The processors in an SMP system do not start all at exactly the same time and therefore the timer registers are typically running at an offset. Some architectures include code that attempts to limit these offsets on bootup. However, the code cannot guarantee to accurately tune the offsets. Glibc contains no provisions to deal with these offsets (unlike the Linux Kernel). ![]() ![]() Typically these offsets are small and therefore the effects may be negligible in most cases. Availability On POSIX systems on which these functions are available, the symbol _POSIX_TIMERS is defined in to a value greater than 0. The symbols _POSIX_MONOTONIC_CLOCK, _POSIX_CPUTIME, _POSIX_THREAD_CPUTIME indicate that CLOCK_MONOTONIC, CLOCK_PROCESS_CPUTIME_ID, CLOCK_THREAD_CPUTIME_ID are available. (See also (3).) Conforming To SUSv2, POSIX.1-2001. See Also (1), (2), (2), (2), (2), (3), (3), (3) Referenced By (3). HRESULT GetTime( [out] MFTIME *phnsClockTime ); Parameters phnsClockTime [out] Receives the latest clock time, in 100-nanosecond units. The time is relative to when the clock was last started. Return value The method returns an HRESULT. Possible values include, but are not limited to, those in the following table. Return code Description S_OK The method succeeded. MF_E_CLOCK_NO_TIME_SOURCE The clock does not have a presentation time source. Remarks This method does not attempt to smooth out jitter or otherwise account for any inaccuracies in the clock time. Requirements Minimum supported client Windows Vista [desktop apps| UWP apps] Minimum supported server Windows Server 2008 [desktop apps| UWP apps] Header Mfidl.h Library Mfuuid.lib See also. GetTime()Category: Control. Time on a computer is calculated from the number of milliseconds elapsed since January 1, 1970. The getTime() method returns the numeric value corresponding to the time for the specified date according to universal time. What is the difference between using new Date() and new Date().getTime() when subtracting two timestamps? (test script on jsFiddle) Both of the following gives the. May 08, 2012 Need some assistance in date frmatting: I'm using: today = new Date(); today.getTime(); How would I format today.getTime() to: YYYY-MM-DD HH:MM:SS.
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