gethrtime -- get high resolution time


       #include <rtl_time.h>

       hrtime_t gethrtime(void);


This function is a non-portable RTLinux extension. gethrtime returns the time in nanoseconds since the system bootup. This time is never reset or adjusted. gethrtime always gives monotonically increasing values. hrtime_t is a 64-bit signed integer.

The HRTIME_INFINITY symbol represents the maximum possible value that gethrtime() could possibly return. This value will be never reached during the execution of the system, and can be used to designate the infinitely distant moment in time.


The actual resolution of gethrtime is hardware-dependent. It is guaranteed to be better than 1 microsecond.

gethrtime is available in PSC, the user-level real-time signal library. It can be called from handlers installed via rtlinux_sigaction(3).


Michael Barabanov (

See Also

UNIX spec clock_gettime(3), clock_gethrtime(3)

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